Research ArticleHistomorphological Description of the Digestive System ofPebbly Fish Alestes baremoze (Joannis 1835)

Nasser Kasozi1 Gerald Iwe Degu1 Julius Mukalazi1 Charles Drago Kato2 Majid Kisekka2

Akisoferi Owori Wadunde3 Godfrey Kityo3 and Victoria Tibenda Namulawa3

1Abi Zonal Agricultural Research amp Development Institute National Agricultural Research OrganisationPO Box 219 Arua Uganda2College of Veterinary Medicine Animal Resources amp Biosecurity Makerere University PO Box 7062 Kampala Uganda3Aquaculture Research amp Development Center National Agricultural Research Organisation PO Box 530 Kampala Uganda

Correspondence should be addressed to Victoria Tibenda Namulawa tibendavykyyahoocom

Received 15 February 2017 Revised 1 May 2017 Accepted 14 May 2017 Published 17 July 2017

Academic Editor Thomas E Adrian

Copyright copy 2017 Nasser Kasozi et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Histomorphological studies of the digestive system of Alestes baremoze captured from Lake Albert Uganda were done usingstandard procedures These revealed that A baremoze has a fleshy-lipped terminal small mouth large molar short oesophagusa three-lobed liver pouch-like stomach a nine-fingered caeca and a long tubular intestine A stratified squamous epitheliumwith numerous mucus-secreting cells lined the lips with no taste buds Stratified squamous epithelia lined the oesophagus inthe anterior portion which turned into a columnar epithelium towards the stomach The lamina propria had numerous tubularglands throughout the entire oesophageal lengthThe stomach consisted of three distinct regions (cardiac fundic and pyloric) withdistinguished lamina propria glands The intestinal mucosa was thrown into villi of varying heights with the tallest in the anteriorpart lined with a simple columnar epithelium with numerous lymphocytes-like infiltrations Numerous goblet cells appeared inthe intestinal lamina epithelialis these increased uniformly towards the anal opening The liver was divided into lobules with acentral vein Hepatocytes were visibly arranged closely forming irregular cords and the scattered tubular acinar glands formedthe exocrine pancreas (hepatopancreas) Stomach content analysis indicated that the fish eats plankton mollusks crustaceans andinsects as the main proportion of its diet

1 Introduction

Alestes baremoze (Joannis 1835) or Pebbly fish is native tofreshwater systems in Africa thriving well in both lacustrineand riverine conditions It belongs to order Characiformesfamily Alestidae and genus Alestes [1] In East Africa the fishappears in Lake Albert Lake Turkana and the Albert andMurchison Niles In Northeast Africa the species is presentin the Ghazal and Jebel systems White and Blue Niles inSudan and the River Nile as far as Lake Nasser In WestAfrica it appears in Chad NigerBenue Volta Comoe andBandama [1] In Uganda Alestes baremoze is a delicacy anda high value fish species particularly in the West-Nile regionwhere it is also popularly known as ldquoAngarardquo [2 3] Studiesindicate that the fish has been extensively harvested putting it

under threat [1] Similarly recent research indicates tremen-dous species decline [2 4] The fact that Alestes baremozeis increasingly getting scare yet greatly demanded on themarket makes it one of the species worth considering forcommercial aquaculture Despite the vast studies conductedto understand the feeding ecology of this fish in Lake Albert[5 6] no information is available on the anatomy of itsdigestive system

Insights into the anatomy of the digestive system ofan aquaculture candidate fish are of importance in guidingdevelopment of appropriate feeding strategies of the fishonce cultured [7 8] The structure of fish gut is a complexsystem [9] responsible for food ingestion digestion andassimilation [10] and the way this is done depends on theanatomical design of the digestive system [11] For this reason

Hindawie Scientific World JournalVolume 2017 Article ID 8591249 9 pageshttpsdoiorg10115520178591249

2 The Scientific World Journal

10 0 10 20

(km)

N

Landing sitesLakes and rivers

Figure 1 Map showing the study site

several studies have been done to describe the structure ofthe digestive system in different fish species [12ndash15] Similarlyseveral research teams have analysed the relative gut length(RGL) in fishes and their feeding regimes [16ndash18] Howeverno such investigation has been done in A baremoze and thislimits the understanding of the functioning of the digestivesystem in this fish and its diet yet such information isimportant to guide the development of feeding strategies infarmed fish The aim of this study therefore was to describethe histomorphology of the digestive system of A baremozeand its RGL and stomach content so as to gain insights intothe functioning of this system such information will guidethe development of appropriate feeding strategies for this fishonce cultured

2 Materials and Methods

21 Sample Collection A total of 20 samples of males andfemales of adult A baremoze were caught using gill netsof 4 inches from Lake Albert and landed at Abok fishlanding site (02∘ 14461015840N 31∘19151015840E) located in Panyimursubcounty on Lake Albert (Figure 1) The fish samples hada mean fork length of 407 (plusmn147) cm and mean bodyweight of 1052 (plusmn277) g The fresh samples were dissectedto expose the entire digestive system The topography andgross anatomy of the digestive system were then describedfollowing successful dissection of the individual organs Ateach dissection step photographs of both the fixed and freshsamples were taken using a digital camera (Kodak EasyShareC763-71 megapixels)

22 Histological Description Tissue sections comprising fourof each of the different digestive system sections (oral cav-ity oesophagus stomach caeca intestine and liver) wereinstantly fixed in Bouinrsquos solution Standard histologicalprocedures [16] were used in tissue processing The preparedtissue sections were stained using haematoxylin and eosin(HampE) and Massonrsquos trichrome staining protocol [17] Thestained sections were then visualised under a Carl Zeiss (Ger-man) light microscope mounted with a 10-megapixel digitalcamera (Canon PowerShot A640 China) Microphotographswere captured and analysed using the ZoomBrowser EXphotographic software (version 20)

23 Relative Gut Length Gut lengths (cm) and total bodylengths (cm) were obtained from 90 samples collected overa period of nine months (pooled samples of males andfemales) The values of relative gut indices of adult A bare-moze were studied [18] using the following formula relativegut length = gut length [cm]standard body length [cm]

24 Stomach Content Analysis The contents of the stomachwere collected separately and preserved in 70 ethanolbefore transportation toMakerereUniversity for analysisThestomach contents were identified under a light microscope(10ndash100x) and analysed using point methods [18 19] Fooditems were awarded points based on the volumes they werejudged to have occupied Stomach fullness was assessed ona 0ndash100-point scale with 0 25 50 75 and 100 representingempty stomach quarter full half full three-quarter full andfull stomachs respectively

The Scientific World Journal 3

50mm

(a)

50mm

(b)

50mm

(c)

50mm

(d)

Figure 2 Gross morphology (a) terminal mouth ( ) (b) dentition ( ) (c) tongue ( ) molar on the dentary ( ) in the lower jaw and(d) molar ( ) and conical teeth ( ) on the premaxilla in the upper jaw

3 Results

31 Gross Morphological Description Alestes baremoze has afusiform shape typical of fast moving fish with relatively largescales It has a bright silver colour which darkens on thedorsal surface with relatively large eyes typical of characinsGross morphological investigations revealed that the oralcavity opens through a fleshy-lipped terminal small mouth(Figure 2(a)) Inside the cavity was a soft textured tongueinclined to the lower jaw and large molars (Figure 2(b))arranged in one raw (Figure 2(c)) The premaxilla had twoteeth rows one composed of conical teeth and the othercomposed of molars (Figure 2(d)) No valve was observedbetween the pharynx and the oesophagus In the viscera(Figure 3(a)) the digestive system lay parallel to the gonadsand the gas bladder The short muscular oesophagus layalongside the liver posterior to the oral cavity and joined thepharynx to the stomach The muscular pouch-like stomachlay adjacent to the three-lobed liver and the anterior section

of the intestine The stomach was divided into the cardiacfundic and pyloric regions The liver had two short lobeson the left with one attached to the gall bladder and onelonger lobe positioned to the right A pyloric sphincteroccurred between the pylorus section of the stomach andthe duodenal section of the intestine where nine-finger-likepyloric caeca were attached (Figure 3(b)) Posterior to theshort duodenum was a looped intestine that lay alongsidethe gonads and gas bladder The intestine had folds similarto those observed in the caeca (Figure 4) The intestinaldiameter gently increased towards its hind section endinginto a narrow annual opening and themean relative intestinallength was 12 plusmn 0085 cm (Table 1)

32 Stomach Contents Analysis Sixteen different prey cat-egories were collected from the stomachs of 90 samplesand recorded Adult A baremoze were found with stomachspredominantly containing insects (8037) with molluscs

4 The Scientific World Journal

Table 1 Relative gut length of A baremoze collected from Lake Albert Uganda

Month Average body length(cm)

Average gut length(cm) Sample number Average relative gut length

April 425 538 10 13May 425 511 20 12June 42 497 10 12July 377 519 5 14August 395 533 7 13September 418 463 11 11October 388 471 8 12November 425 498 10 12December 403 50 9 12Average RGL for all samples (April to December) = 12 plusmn 0085

IN

Go

Li

G

50mm

(a)

Li

Ce St

Gb

R

InOes

50mm

(b)

Figure 3 (a) Topography of the GIT and associated organs gonad (Go) gas bladder (G) liver (Li) and intestine (IN) (b) Organs of the GIToesophagus (Oes) liver (Li) rectum (R) stomach (St) intestine (In) gall bladder (Gb) and caeca (Ce)

(5)

(1)

(3)(8)

(7)

(2)

(4)

(6)

Figure 4 Structure of the digestive tract of A baremoze (1)Esophagus (2) cardiac stomach (3) fundic stomach (4) pyloricstomach (5) pyloric caeca (6) anterior intestine (7) mid intestineand (8) posterior intestinerectum

crustaceans and food items constituting lesser proportions(Table 2)

33 Histology

331 Lip The lip surfacewas linedwith a stratified squamousepithelium and numerousmucous secreting cells Underlyingthis was cartilaginous and skeletal muscle No taste buds wereobserved in the lip (Figure 5(a))

332 Palate The roof of the oral cavity was formed bya palate lined by a stratified squamous epithelium withnumerous epithelial folds (Figure 5(b)) Below this was thelamina muscularis which formed a demarcation betweenthe epithelial layer and the propria submucosa The pro-pria submucosa of the palate was made of dense irregularconnective tissue Beneath this underlay cartilage and bone(Figure 5(c))

333 Tongue The tongue was lined by a stratified squamousepithelium on the dorsum with numerous lymphocytes-cell-like infiltrations (Figure 5(d)) The propria submucosa of thetongue was made of loose connective tissue with numerousadipose tissues A thin layer of skeletal muscle the laminamuscularis separated the lamina epithelialis from the propriasubmucosaThe bulk of the tongue was shaped by underlyingcartilage

334 Oesophagus The oesophagus was lined by a stratifiedsquamous epithelium in the anterior portion which turnedinto a columnar epithelium towards the cardiac stomach(Figure 6) The lamina propria had numerous tubular glandsthroughout the entire length of the oesophagus The mucosawas thrown into several folds supported by loose connectivetissue from the submucosa Numerous blood vessels wereobserved in the submucosa The tunica muscularis had aninner circular muscle layer and an outer longitudinal skeletalmuscle layer Tunica muscularis turned from skeletal tosmooth muscle towards the stomach

The Scientific World Journal 5

Table 2 Point assessment percentages of various categories of food items in the stomachs of Alestes baremoze collected from Lake AlbertUganda during the year 2016

Category Food items Point assessment percentages

Insecta

Remains of winged insect 90Dragonflies 80

Ephemeroptera (nymph) 77Adult grasshoppers 745

Mollusca Gastropoda 475

Crustacea

Ostracoda 453Daphnia 27Shrimps 27Cyclops 17Moina 11

Other food items

Detritus 229Phytoplankton (Microcystis and Chlorella) 26

Eggs 258Fish scales 25Small stones 21Round worms 05

SM SSEE

50 120583m

(a)

SM

ADP

ADP

B

M

50 120583m

(b)

E

LM PSM

S

50 120583m

(c)

CT

SM

50 120583m

(d)

Figure 5 Oral cavity (a) Lips skeletal muscles (SM) and stratified squamous epithelium (SSE) with goblet cells (arrows) (b) Palate-roof ofthe oral cavity epithelium (E) submucosa (SM) with irregular connective tissue adipose tissue (ADP) skeletal muscle (M) and underlyingbone (B) (c) Floor of the oral cavity epithelium (E) laminar muscularis (LM) propria submucosa (PSM) and skeletal muscle (SM) (d)Tongue adipose tissue (arrows) skeletal muscle (SM) connective tissue (CT) and underlying cartilage (C)

335 Stomach The stomach consisted of three distinctregions that were distinguished on the basis of glands in thelamina propria the cardiac fundic and pyloric regions In allthe parts the stomachwas lined by a simple columnar epithe-lium Laminar muscularis was not observed in the stomach

The lamina propria had numerous straight tubular glands(Figure 7(a)) that appeared shorter in the pyloric region ascompared to the fundic and cardiac regions The submucosawas made of loose connective tissue with numerous bloodvessels Tunica muscularis consisted of inner circular and

6 The Scientific World Journal

LM

CMBV

BV

SM LP

25 120583m

Figure 6 Transverse section of esophagus lamina propria (LP)submucosa (SM) blood vessel (BV) inner circular muscle (CM)and outer longitudinal muscle (LM) Arrows tubular glands

outer longitudinal smooth muscle layers (Figure 7(b)) Thelongitudinal muscle layer was slightly thicker in the fundicregion of the stomach The serosa was a single layer ofsquamous cells beneath the muscularis

336 Liver The liver was divided into lobules by connec-tive tissue sheets with a central vein in the middle (Fig-ure 8(a)) The hepatocytes were visible throughout the liverparenchyma arranged close to each other forming irregularcords Throughout the liver lobules were scattered tubularacinar glands of the exocrine pancreas forming the hepat-opancreas and secretory vesicles (Figure 8(b))

337 Intestine Themucosal layer of the intestine was throwninto folds (villi) of varying sizes (Figure 9(a)) Villi weretallest in the anterior part of the intestine The mucosa waslined with a simple columnar epithelium with numerouslymphocytes cell-like infiltrations Numerous goblet cellsthat increased in number towards the anal opening wereseen in the lamina epithelialis The submucosa was thinwith its connective tissue extending the entire length of thevilli Tunica muscularis was made up of inner circular andouter longitudinal layer of smooth muscle (Figure 9(b)) Thehistological organization of the caeca was identical to thatof the anterior and posterior intestine but with less villi andgoblet cells

4 Discussion

Histomorphological studies in fish have increasingly becomeimportant given the growing interest in aquaculture [20]since the structure of the digestive system in fish indicates itsfeeding behaviour and provides insights into feeding strate-gies for cultured fish [21 22] Gross morphological investiga-tions in this study revealed that the oral cavity inA baremoze

LM

CM

SM

LPE

L

50 120583m

(a)

CMSM

LP

50 120583m

(b)

Figure 7 Transverse section through the stomach (a) Cardiacstomach and (b) fundic stomach lumen (L) epithelium (E) sub-mucosa (SM) lamina propria (LP) circular muscle layer (CM) andlongitudinal muscle (LM)

is composed of a small fleshy-lipped terminal mouth withboth conical andmolariformdentitions Similarmouth struc-tures have been observed in Cheilinus lunulatus [23] withmolariform and conical teeth common in Clarias gariepinus[24] Herichthys minckleyi [25] Aphanius persicus [26] andChrysobrycon eliasi [27] Terminal mouths in fish have beenrelated to chasing and capture of small food items [28]while the presence of teeth on the jaws enables the predatorto hold and grasp prey items [29] Similarly conical denti-tions have been associated with soft bodied predators [30]while molariform dentations have been associated with mol-lusc and crustacean feeders [23] The presence of these twodentition types in A baremoze suggests that this fish feeds ona variety of food items but mainly of animal origin Histo-logical investigations further revealed the presence of severalgoblet cells in the epithelium lining the oral cavity severalskeletal muscles adipose tissue and an underlying cartilagein the cavity Similar observations have been reported inOreochromis niloticus and Clarias gariepinus [31] wherepresence of mucus secreting glands was suggested to implysecretion of copious amounts of mucus needed to lubricatethe oral cavity to ease swallowing Meanwhile the presence ofmuscle networks and adipose tissue suggests ease of mouthmovement duringmastication and a cushion of fat cells to actas a shock absorber during food acquisition and swallowing

The Scientific World Journal 7

CV

ExP25 120583m

(a)

SV

ExP

25 120583m

(b)

Figure 8 Liver (a) CV central vein and (b) ExP exocrine pancreas with secretory vesicles (SV) with hepatocytes arranged in irregularcords

LM

V

V

SM

50 120583m

(a)

SM

E

LM SE

50 120583m

(b)

Figure 9 Intestine E epithelium SM submucosa V villi SE serosa and LM longitudinal muscle arrows are goblet cells

The oesophagus in A baremoze in this study is shortand has numerous tubular glands located in the laminapropria The mucosa is also greatly folded while the tunicamuscularis is well developed with inner circular musclesand outer longitudinal skeletal muscles Similar reports havebeen given in other fishes such as Clarias gariepinus andCtenopharyngodon idella [32] All these studies conclude thatthe numerous mucosal folds provide for increased surfacearea for chemical activity Similarly several tubular glandswere also observed in the lamina propria of the oesophagusin A baremoze in this study This therefore suggests thatchemical digestion in A baremoze begins in the oesophagus

Study results reveal the presence of a pouch-like stomachinA baremozewhose lamina propria had numerous straighttubular glands as has been reported in Esox lucius [3334] and Lates niloticus [35] In these fishes the presenceof a pouch-shaped stomach has been related to large feedquantity intake which is slowly digested by chemical sub-stances released from the tubular glands This could be themechanism of digestion also occurring in A baremoze

Morphological observations indicated that the liver inA baremoze is three-lobed and lies adjacent to the oesoph-agus stomach and the anterior section of the intestineHistologically the liver parenchyma contained tubular acinarglands which constituted the exocrine pancreas formingthe hepatopancreas This arrangement is similar to whatwas observed in several fish and freshwater bivalves [1736] However the hepatopancreas is not observed in highervertebrates [37]

Similarly observations made in this study reveal thatA baremoze has a nine-fingered caeca and a long tubularintestine lying alongside the gonadsMultifingered caeca havebeen reported in several other fishes and have been proposedto be important in chemical digestion [38] absorption [39]osmoregulation [40] food storage lipid absorption and opti-mising pH for digestion [41] Histologically the organisationof the intestine did not significantly differ from that of thecaecaThe arrangement of this structure is in agreement withfindings by [42] and is suitable for absorbing digested food[43]

8 The Scientific World Journal

The RGL of A baremoze in this study was 12 plusmn 0085(Table 1) The relationship between RGL and trophic levels infishes has been documented [15]This relationship is believedto reflect the digestive processing time required for differentfood material Herbivorous fish species for instance tend tohave higher RGL compared to omnivorous and carnivorousfishes due to the fibrous plant material they ingest whichrequires longer digestion time Although the RGL varies withfish species and growth stages [16] categorises fish as eithercarnivorous (RGL=06ndash08) omnivorous (RGL=08ndash10) orherbivorous (RGL = 25ndash164)This suggests thatA baremozeis an omnivorous fish a situation confirmed by observationsmade from its stomach contents (Table 2) which were seento cut across plant and animal material According to [1] Abaremoze has a flexible diet shifting from zooplankton tozoobenthos detritus and macrophytes as plankton densitiesdecline Findings reported by [6] on food web structure inLake Albert suggest that ontogenetic shifts occurred in thediet of A baremoze and this was partly driven by structuralchanges in feeding apparatus and morphology that openedup new and unexploited feeding opportunities Similarly sizespecific shifts in food or habitat type have been documentedin many species [44 45] Previous studies related to feedingecology on one of the closest relatives Alestes nurse inthe Alestidae family by [44] indicated that A nurse wasobserved to change its food diet from phytoplankton andsmall zooplankton during their premetamorphosis stages tolarger zooplankton The observed dietary shifts observed inA baremoze suggest that this fish can survive on a variety offood items and this makes it a good aquaculture candidatewith ability to survive on formulated diets given that theseare developed from a variety of raw materials both of planand animal origin

5 Conclusion

Histomorphological observations and stomach content anal-ysis performed in this study suggest that A baremoze hasmorphological adaptations for omnivory The molariformdentation observed in the adult fish also helps them to feed onhard bodied organisms Further investigations to assess theability ofA baremoze to digest formulated diets will be useful

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the grant from the Compet-itive Grant Scheme of the National Agricultural ResearchOrganisation (NARO) under the Agricultural Technologyand Agribusiness Advisory Services (ATAAS) project andwas implemented by Abi Zonal Agricultural Research andDevelopment Institute (Abi ZARDI) CGS Project IDnoCGS43214

References

[1] E Akinyi A Awaıss A Azeroual A Getahun P Laleye andT Twongo ldquoAlestes baremozerdquo in IUCN 2012 IUCN Red List ofThreatened Species Version 20122 2010

[2] DMbabazi M A Taabu L I Muhoozi et al ldquoThe past presentand projected scenarios in the lake Albert and Albert nilefisheries implications for sustainable managementrdquo UgandaJournal of Agricultural Sciences vol 13 no 2 pp 47ndash64 2012

[3] N Kasozi G I Degu K Atibuni M Kisekka A Owori-Wadunde and S Mugerwa ldquoClassification of ovarian stages ofAlestes baremoze (Joannis 1835) a step towards understandingits reproductive biologyrdquo Frontiers in Science vol 3 no 4 pp107ndash113 2013

[4] ldquoNaFIRRI (National Fisheries Resources Research Institute)rdquoCapture fisheries in UgandaTheNile perch fishery Traditionaland Emerging Fisheries Overfishing and the use of illegal gearson Lake Albert Jinja Uganda Policy Brief No 1 2012

[5] M J Holden ldquoThe feeding habits of Alestes baremose andHydrocynus forskali (Pisces) in Lake Albert East AfricardquoJournal of Zoology vol 161 no 1 pp 137ndash144 1970

[6] L M Campbell S B Wandera R J Thacker D G Dixonand R E Hecky ldquoTrophic niche segregation in the Niloticichthyofauna of Lake Albert (Uganda Africa)rdquo EnvironmentalBiology of Fishes vol 74 no 3-4 pp 247ndash260 2005

[7] K L Riley C R Weirich and D Cerino ldquoDevelopment andgrowth of hatchery-reared larval Florida pompano (Trachinotuscarolinus)rdquo Fishery Bulletin vol 107 no 3 pp 318ndash328 2009

[8] I Roslashnnestad M Yufera B Ueberschar L Ribeiro Oslash Saeligleand C Boglione ldquoFeeding behaviour and digestive physiologyin larval fish Current knowledge and gaps and bottlenecks inresearchrdquo Reviews in Aquaculture vol 5 no 1 pp S59ndashS982013

[9] J Abowei and A T Ekubo ldquoSome principles and requirementsin fish nutritionrdquo British Journal of Pharmacology and Toxicol-ogy vol 2 no 4 pp 163ndash178 2011

[10] J Sweetman A Dimitroglou S Davies and S TorrecillasldquoNutrient uptake gut morphology a key to efficient nutritionrdquoInternational Aqua Feed vol 8 pp 26ndash30 2008

[11] R K Buddington A Krogdahl and A M Bakke-MckellepldquoThe intestines of carnivorous fish structure and functionsand the relations with dietrdquo Acta Physiologica ScandinavicaSupplementum no 638 pp 67ndash80 1997

[12] R Hofer ldquoMorphological adaptations of the digestive tract oftropical cyprinids and cichlids to dietrdquo Journal of Fish Biologyvol 33 no 3 pp 399ndash408 1988

[13] C Ribeiro and E Fanta ldquoMicroscopic morphology and histo-chemistry of the digestive system of a tropical freshwater fishTrichomycterus brasiliensis (Lutken) (Siluroidei Trichomycteri-dae)rdquo Revista Brasileira de Zoologia vol 17 no 4 pp 953ndash9712000

[14] W H Karasov C Martınez Del Rio and E Caviedes-VidalldquoEcological physiology of diet and digestive systemsrdquo AnnualReview of Physiology vol 73 pp 69ndash93 2011

[15] B CananW S do Nascimento N B da Silva and S ChellappaldquoMorphohistology of the digestive tract of the damsel fishStegastes fuscus (Osteichthyes Pomacentridae)rdquo The ScientificWorld Journal vol 2012 Article ID 787316 9 pages 2012

[16] D P German andMHHorn ldquoGut length andmass in herbivo-rous and carnivorous prickleback fishes (Teleostei Stichaeidae)Ontogenetic dietary and phylogenetic effectsrdquoMarine Biologyvol 148 no 5 pp 1123ndash1134 2006

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

The Scientific World Journal 3

50mm

(a)

50mm

(b)

50mm

(c)

50mm

(d)

Figure 2 Gross morphology (a) terminal mouth ( ) (b) dentition ( ) (c) tongue ( ) molar on the dentary ( ) in the lower jaw and(d) molar ( ) and conical teeth ( ) on the premaxilla in the upper jaw

3 Results

31 Gross Morphological Description Alestes baremoze has afusiform shape typical of fast moving fish with relatively largescales It has a bright silver colour which darkens on thedorsal surface with relatively large eyes typical of characinsGross morphological investigations revealed that the oralcavity opens through a fleshy-lipped terminal small mouth(Figure 2(a)) Inside the cavity was a soft textured tongueinclined to the lower jaw and large molars (Figure 2(b))arranged in one raw (Figure 2(c)) The premaxilla had twoteeth rows one composed of conical teeth and the othercomposed of molars (Figure 2(d)) No valve was observedbetween the pharynx and the oesophagus In the viscera(Figure 3(a)) the digestive system lay parallel to the gonadsand the gas bladder The short muscular oesophagus layalongside the liver posterior to the oral cavity and joined thepharynx to the stomach The muscular pouch-like stomachlay adjacent to the three-lobed liver and the anterior section

of the intestine The stomach was divided into the cardiacfundic and pyloric regions The liver had two short lobeson the left with one attached to the gall bladder and onelonger lobe positioned to the right A pyloric sphincteroccurred between the pylorus section of the stomach andthe duodenal section of the intestine where nine-finger-likepyloric caeca were attached (Figure 3(b)) Posterior to theshort duodenum was a looped intestine that lay alongsidethe gonads and gas bladder The intestine had folds similarto those observed in the caeca (Figure 4) The intestinaldiameter gently increased towards its hind section endinginto a narrow annual opening and themean relative intestinallength was 12 plusmn 0085 cm (Table 1)

32 Stomach Contents Analysis Sixteen different prey cat-egories were collected from the stomachs of 90 samplesand recorded Adult A baremoze were found with stomachspredominantly containing insects (8037) with molluscs

4 The Scientific World Journal

Table 1 Relative gut length of A baremoze collected from Lake Albert Uganda

Month Average body length(cm)

Average gut length(cm) Sample number Average relative gut length

April 425 538 10 13May 425 511 20 12June 42 497 10 12July 377 519 5 14August 395 533 7 13September 418 463 11 11October 388 471 8 12November 425 498 10 12December 403 50 9 12Average RGL for all samples (April to December) = 12 plusmn 0085

IN

Go

Li

G

50mm

(a)

Li

Ce St

Gb

R

InOes

50mm

(b)

Figure 3 (a) Topography of the GIT and associated organs gonad (Go) gas bladder (G) liver (Li) and intestine (IN) (b) Organs of the GIToesophagus (Oes) liver (Li) rectum (R) stomach (St) intestine (In) gall bladder (Gb) and caeca (Ce)

(5)

(1)

(3)(8)

(7)

(2)

(4)

(6)

Figure 4 Structure of the digestive tract of A baremoze (1)Esophagus (2) cardiac stomach (3) fundic stomach (4) pyloricstomach (5) pyloric caeca (6) anterior intestine (7) mid intestineand (8) posterior intestinerectum

crustaceans and food items constituting lesser proportions(Table 2)

33 Histology

331 Lip The lip surfacewas linedwith a stratified squamousepithelium and numerousmucous secreting cells Underlyingthis was cartilaginous and skeletal muscle No taste buds wereobserved in the lip (Figure 5(a))

332 Palate The roof of the oral cavity was formed bya palate lined by a stratified squamous epithelium withnumerous epithelial folds (Figure 5(b)) Below this was thelamina muscularis which formed a demarcation betweenthe epithelial layer and the propria submucosa The pro-pria submucosa of the palate was made of dense irregularconnective tissue Beneath this underlay cartilage and bone(Figure 5(c))

333 Tongue The tongue was lined by a stratified squamousepithelium on the dorsum with numerous lymphocytes-cell-like infiltrations (Figure 5(d)) The propria submucosa of thetongue was made of loose connective tissue with numerousadipose tissues A thin layer of skeletal muscle the laminamuscularis separated the lamina epithelialis from the propriasubmucosaThe bulk of the tongue was shaped by underlyingcartilage

334 Oesophagus The oesophagus was lined by a stratifiedsquamous epithelium in the anterior portion which turnedinto a columnar epithelium towards the cardiac stomach(Figure 6) The lamina propria had numerous tubular glandsthroughout the entire length of the oesophagus The mucosawas thrown into several folds supported by loose connectivetissue from the submucosa Numerous blood vessels wereobserved in the submucosa The tunica muscularis had aninner circular muscle layer and an outer longitudinal skeletalmuscle layer Tunica muscularis turned from skeletal tosmooth muscle towards the stomach

The Scientific World Journal 5

Table 2 Point assessment percentages of various categories of food items in the stomachs of Alestes baremoze collected from Lake AlbertUganda during the year 2016

Category Food items Point assessment percentages

Insecta

Remains of winged insect 90Dragonflies 80

Ephemeroptera (nymph) 77Adult grasshoppers 745

Mollusca Gastropoda 475

Crustacea

Ostracoda 453Daphnia 27Shrimps 27Cyclops 17Moina 11

Other food items

Detritus 229Phytoplankton (Microcystis and Chlorella) 26

Eggs 258Fish scales 25Small stones 21Round worms 05

SM SSEE

50 120583m

(a)

SM

ADP

ADP

B

M

50 120583m

(b)

E

LM PSM

S

50 120583m

(c)

CT

SM

50 120583m

(d)

Figure 5 Oral cavity (a) Lips skeletal muscles (SM) and stratified squamous epithelium (SSE) with goblet cells (arrows) (b) Palate-roof ofthe oral cavity epithelium (E) submucosa (SM) with irregular connective tissue adipose tissue (ADP) skeletal muscle (M) and underlyingbone (B) (c) Floor of the oral cavity epithelium (E) laminar muscularis (LM) propria submucosa (PSM) and skeletal muscle (SM) (d)Tongue adipose tissue (arrows) skeletal muscle (SM) connective tissue (CT) and underlying cartilage (C)

335 Stomach The stomach consisted of three distinctregions that were distinguished on the basis of glands in thelamina propria the cardiac fundic and pyloric regions In allthe parts the stomachwas lined by a simple columnar epithe-lium Laminar muscularis was not observed in the stomach

The lamina propria had numerous straight tubular glands(Figure 7(a)) that appeared shorter in the pyloric region ascompared to the fundic and cardiac regions The submucosawas made of loose connective tissue with numerous bloodvessels Tunica muscularis consisted of inner circular and

6 The Scientific World Journal

LM

CMBV

BV

SM LP

25 120583m

Figure 6 Transverse section of esophagus lamina propria (LP)submucosa (SM) blood vessel (BV) inner circular muscle (CM)and outer longitudinal muscle (LM) Arrows tubular glands

outer longitudinal smooth muscle layers (Figure 7(b)) Thelongitudinal muscle layer was slightly thicker in the fundicregion of the stomach The serosa was a single layer ofsquamous cells beneath the muscularis

336 Liver The liver was divided into lobules by connec-tive tissue sheets with a central vein in the middle (Fig-ure 8(a)) The hepatocytes were visible throughout the liverparenchyma arranged close to each other forming irregularcords Throughout the liver lobules were scattered tubularacinar glands of the exocrine pancreas forming the hepat-opancreas and secretory vesicles (Figure 8(b))

337 Intestine Themucosal layer of the intestine was throwninto folds (villi) of varying sizes (Figure 9(a)) Villi weretallest in the anterior part of the intestine The mucosa waslined with a simple columnar epithelium with numerouslymphocytes cell-like infiltrations Numerous goblet cellsthat increased in number towards the anal opening wereseen in the lamina epithelialis The submucosa was thinwith its connective tissue extending the entire length of thevilli Tunica muscularis was made up of inner circular andouter longitudinal layer of smooth muscle (Figure 9(b)) Thehistological organization of the caeca was identical to thatof the anterior and posterior intestine but with less villi andgoblet cells

4 Discussion

Histomorphological studies in fish have increasingly becomeimportant given the growing interest in aquaculture [20]since the structure of the digestive system in fish indicates itsfeeding behaviour and provides insights into feeding strate-gies for cultured fish [21 22] Gross morphological investiga-tions in this study revealed that the oral cavity inA baremoze

LM

CM

SM

LPE

L

50 120583m

(a)

CMSM

LP

50 120583m

(b)

Figure 7 Transverse section through the stomach (a) Cardiacstomach and (b) fundic stomach lumen (L) epithelium (E) sub-mucosa (SM) lamina propria (LP) circular muscle layer (CM) andlongitudinal muscle (LM)

is composed of a small fleshy-lipped terminal mouth withboth conical andmolariformdentitions Similarmouth struc-tures have been observed in Cheilinus lunulatus [23] withmolariform and conical teeth common in Clarias gariepinus[24] Herichthys minckleyi [25] Aphanius persicus [26] andChrysobrycon eliasi [27] Terminal mouths in fish have beenrelated to chasing and capture of small food items [28]while the presence of teeth on the jaws enables the predatorto hold and grasp prey items [29] Similarly conical denti-tions have been associated with soft bodied predators [30]while molariform dentations have been associated with mol-lusc and crustacean feeders [23] The presence of these twodentition types in A baremoze suggests that this fish feeds ona variety of food items but mainly of animal origin Histo-logical investigations further revealed the presence of severalgoblet cells in the epithelium lining the oral cavity severalskeletal muscles adipose tissue and an underlying cartilagein the cavity Similar observations have been reported inOreochromis niloticus and Clarias gariepinus [31] wherepresence of mucus secreting glands was suggested to implysecretion of copious amounts of mucus needed to lubricatethe oral cavity to ease swallowing Meanwhile the presence ofmuscle networks and adipose tissue suggests ease of mouthmovement duringmastication and a cushion of fat cells to actas a shock absorber during food acquisition and swallowing

The Scientific World Journal 7

CV

ExP25 120583m

(a)

SV

ExP

25 120583m

(b)

Figure 8 Liver (a) CV central vein and (b) ExP exocrine pancreas with secretory vesicles (SV) with hepatocytes arranged in irregularcords

LM

V

V

SM

50 120583m

(a)

SM

E

LM SE

50 120583m

(b)

Figure 9 Intestine E epithelium SM submucosa V villi SE serosa and LM longitudinal muscle arrows are goblet cells

The oesophagus in A baremoze in this study is shortand has numerous tubular glands located in the laminapropria The mucosa is also greatly folded while the tunicamuscularis is well developed with inner circular musclesand outer longitudinal skeletal muscles Similar reports havebeen given in other fishes such as Clarias gariepinus andCtenopharyngodon idella [32] All these studies conclude thatthe numerous mucosal folds provide for increased surfacearea for chemical activity Similarly several tubular glandswere also observed in the lamina propria of the oesophagusin A baremoze in this study This therefore suggests thatchemical digestion in A baremoze begins in the oesophagus

Study results reveal the presence of a pouch-like stomachinA baremozewhose lamina propria had numerous straighttubular glands as has been reported in Esox lucius [3334] and Lates niloticus [35] In these fishes the presenceof a pouch-shaped stomach has been related to large feedquantity intake which is slowly digested by chemical sub-stances released from the tubular glands This could be themechanism of digestion also occurring in A baremoze

Morphological observations indicated that the liver inA baremoze is three-lobed and lies adjacent to the oesoph-agus stomach and the anterior section of the intestineHistologically the liver parenchyma contained tubular acinarglands which constituted the exocrine pancreas formingthe hepatopancreas This arrangement is similar to whatwas observed in several fish and freshwater bivalves [1736] However the hepatopancreas is not observed in highervertebrates [37]

Similarly observations made in this study reveal thatA baremoze has a nine-fingered caeca and a long tubularintestine lying alongside the gonadsMultifingered caeca havebeen reported in several other fishes and have been proposedto be important in chemical digestion [38] absorption [39]osmoregulation [40] food storage lipid absorption and opti-mising pH for digestion [41] Histologically the organisationof the intestine did not significantly differ from that of thecaecaThe arrangement of this structure is in agreement withfindings by [42] and is suitable for absorbing digested food[43]

8 The Scientific World Journal

The RGL of A baremoze in this study was 12 plusmn 0085(Table 1) The relationship between RGL and trophic levels infishes has been documented [15]This relationship is believedto reflect the digestive processing time required for differentfood material Herbivorous fish species for instance tend tohave higher RGL compared to omnivorous and carnivorousfishes due to the fibrous plant material they ingest whichrequires longer digestion time Although the RGL varies withfish species and growth stages [16] categorises fish as eithercarnivorous (RGL=06ndash08) omnivorous (RGL=08ndash10) orherbivorous (RGL = 25ndash164)This suggests thatA baremozeis an omnivorous fish a situation confirmed by observationsmade from its stomach contents (Table 2) which were seento cut across plant and animal material According to [1] Abaremoze has a flexible diet shifting from zooplankton tozoobenthos detritus and macrophytes as plankton densitiesdecline Findings reported by [6] on food web structure inLake Albert suggest that ontogenetic shifts occurred in thediet of A baremoze and this was partly driven by structuralchanges in feeding apparatus and morphology that openedup new and unexploited feeding opportunities Similarly sizespecific shifts in food or habitat type have been documentedin many species [44 45] Previous studies related to feedingecology on one of the closest relatives Alestes nurse inthe Alestidae family by [44] indicated that A nurse wasobserved to change its food diet from phytoplankton andsmall zooplankton during their premetamorphosis stages tolarger zooplankton The observed dietary shifts observed inA baremoze suggest that this fish can survive on a variety offood items and this makes it a good aquaculture candidatewith ability to survive on formulated diets given that theseare developed from a variety of raw materials both of planand animal origin

5 Conclusion

Histomorphological observations and stomach content anal-ysis performed in this study suggest that A baremoze hasmorphological adaptations for omnivory The molariformdentation observed in the adult fish also helps them to feed onhard bodied organisms Further investigations to assess theability ofA baremoze to digest formulated diets will be useful

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the grant from the Compet-itive Grant Scheme of the National Agricultural ResearchOrganisation (NARO) under the Agricultural Technologyand Agribusiness Advisory Services (ATAAS) project andwas implemented by Abi Zonal Agricultural Research andDevelopment Institute (Abi ZARDI) CGS Project IDnoCGS43214

References

[1] E Akinyi A Awaıss A Azeroual A Getahun P Laleye andT Twongo ldquoAlestes baremozerdquo in IUCN 2012 IUCN Red List ofThreatened Species Version 20122 2010

[2] DMbabazi M A Taabu L I Muhoozi et al ldquoThe past presentand projected scenarios in the lake Albert and Albert nilefisheries implications for sustainable managementrdquo UgandaJournal of Agricultural Sciences vol 13 no 2 pp 47ndash64 2012

[3] N Kasozi G I Degu K Atibuni M Kisekka A Owori-Wadunde and S Mugerwa ldquoClassification of ovarian stages ofAlestes baremoze (Joannis 1835) a step towards understandingits reproductive biologyrdquo Frontiers in Science vol 3 no 4 pp107ndash113 2013

[4] ldquoNaFIRRI (National Fisheries Resources Research Institute)rdquoCapture fisheries in UgandaTheNile perch fishery Traditionaland Emerging Fisheries Overfishing and the use of illegal gearson Lake Albert Jinja Uganda Policy Brief No 1 2012

[5] M J Holden ldquoThe feeding habits of Alestes baremose andHydrocynus forskali (Pisces) in Lake Albert East AfricardquoJournal of Zoology vol 161 no 1 pp 137ndash144 1970

[6] L M Campbell S B Wandera R J Thacker D G Dixonand R E Hecky ldquoTrophic niche segregation in the Niloticichthyofauna of Lake Albert (Uganda Africa)rdquo EnvironmentalBiology of Fishes vol 74 no 3-4 pp 247ndash260 2005

[7] K L Riley C R Weirich and D Cerino ldquoDevelopment andgrowth of hatchery-reared larval Florida pompano (Trachinotuscarolinus)rdquo Fishery Bulletin vol 107 no 3 pp 318ndash328 2009

[8] I Roslashnnestad M Yufera B Ueberschar L Ribeiro Oslash Saeligleand C Boglione ldquoFeeding behaviour and digestive physiologyin larval fish Current knowledge and gaps and bottlenecks inresearchrdquo Reviews in Aquaculture vol 5 no 1 pp S59ndashS982013

[9] J Abowei and A T Ekubo ldquoSome principles and requirementsin fish nutritionrdquo British Journal of Pharmacology and Toxicol-ogy vol 2 no 4 pp 163ndash178 2011

[10] J Sweetman A Dimitroglou S Davies and S TorrecillasldquoNutrient uptake gut morphology a key to efficient nutritionrdquoInternational Aqua Feed vol 8 pp 26ndash30 2008

[11] R K Buddington A Krogdahl and A M Bakke-MckellepldquoThe intestines of carnivorous fish structure and functionsand the relations with dietrdquo Acta Physiologica ScandinavicaSupplementum no 638 pp 67ndash80 1997

[12] R Hofer ldquoMorphological adaptations of the digestive tract oftropical cyprinids and cichlids to dietrdquo Journal of Fish Biologyvol 33 no 3 pp 399ndash408 1988

[13] C Ribeiro and E Fanta ldquoMicroscopic morphology and histo-chemistry of the digestive system of a tropical freshwater fishTrichomycterus brasiliensis (Lutken) (Siluroidei Trichomycteri-dae)rdquo Revista Brasileira de Zoologia vol 17 no 4 pp 953ndash9712000

[14] W H Karasov C Martınez Del Rio and E Caviedes-VidalldquoEcological physiology of diet and digestive systemsrdquo AnnualReview of Physiology vol 73 pp 69ndash93 2011

[15] B CananW S do Nascimento N B da Silva and S ChellappaldquoMorphohistology of the digestive tract of the damsel fishStegastes fuscus (Osteichthyes Pomacentridae)rdquo The ScientificWorld Journal vol 2012 Article ID 787316 9 pages 2012

[16] D P German andMHHorn ldquoGut length andmass in herbivo-rous and carnivorous prickleback fishes (Teleostei Stichaeidae)Ontogenetic dietary and phylogenetic effectsrdquoMarine Biologyvol 148 no 5 pp 1123ndash1134 2006

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

4 The Scientific World Journal

Table 1 Relative gut length of A baremoze collected from Lake Albert Uganda

Month Average body length(cm)

Average gut length(cm) Sample number Average relative gut length

April 425 538 10 13May 425 511 20 12June 42 497 10 12July 377 519 5 14August 395 533 7 13September 418 463 11 11October 388 471 8 12November 425 498 10 12December 403 50 9 12Average RGL for all samples (April to December) = 12 plusmn 0085

IN

Go

Li

G

50mm

(a)

Li

Ce St

Gb

R

InOes

50mm

(b)

Figure 3 (a) Topography of the GIT and associated organs gonad (Go) gas bladder (G) liver (Li) and intestine (IN) (b) Organs of the GIToesophagus (Oes) liver (Li) rectum (R) stomach (St) intestine (In) gall bladder (Gb) and caeca (Ce)

(5)

(1)

(3)(8)

(7)

(2)

(4)

(6)

Figure 4 Structure of the digestive tract of A baremoze (1)Esophagus (2) cardiac stomach (3) fundic stomach (4) pyloricstomach (5) pyloric caeca (6) anterior intestine (7) mid intestineand (8) posterior intestinerectum

crustaceans and food items constituting lesser proportions(Table 2)

33 Histology

331 Lip The lip surfacewas linedwith a stratified squamousepithelium and numerousmucous secreting cells Underlyingthis was cartilaginous and skeletal muscle No taste buds wereobserved in the lip (Figure 5(a))

332 Palate The roof of the oral cavity was formed bya palate lined by a stratified squamous epithelium withnumerous epithelial folds (Figure 5(b)) Below this was thelamina muscularis which formed a demarcation betweenthe epithelial layer and the propria submucosa The pro-pria submucosa of the palate was made of dense irregularconnective tissue Beneath this underlay cartilage and bone(Figure 5(c))

333 Tongue The tongue was lined by a stratified squamousepithelium on the dorsum with numerous lymphocytes-cell-like infiltrations (Figure 5(d)) The propria submucosa of thetongue was made of loose connective tissue with numerousadipose tissues A thin layer of skeletal muscle the laminamuscularis separated the lamina epithelialis from the propriasubmucosaThe bulk of the tongue was shaped by underlyingcartilage

334 Oesophagus The oesophagus was lined by a stratifiedsquamous epithelium in the anterior portion which turnedinto a columnar epithelium towards the cardiac stomach(Figure 6) The lamina propria had numerous tubular glandsthroughout the entire length of the oesophagus The mucosawas thrown into several folds supported by loose connectivetissue from the submucosa Numerous blood vessels wereobserved in the submucosa The tunica muscularis had aninner circular muscle layer and an outer longitudinal skeletalmuscle layer Tunica muscularis turned from skeletal tosmooth muscle towards the stomach

The Scientific World Journal 5

Table 2 Point assessment percentages of various categories of food items in the stomachs of Alestes baremoze collected from Lake AlbertUganda during the year 2016

Category Food items Point assessment percentages

Insecta

Remains of winged insect 90Dragonflies 80

Ephemeroptera (nymph) 77Adult grasshoppers 745

Mollusca Gastropoda 475

Crustacea

Ostracoda 453Daphnia 27Shrimps 27Cyclops 17Moina 11

Other food items

Detritus 229Phytoplankton (Microcystis and Chlorella) 26

Eggs 258Fish scales 25Small stones 21Round worms 05

SM SSEE

50 120583m

(a)

SM

ADP

ADP

B

M

50 120583m

(b)

E

LM PSM

S

50 120583m

(c)

CT

SM

50 120583m

(d)

Figure 5 Oral cavity (a) Lips skeletal muscles (SM) and stratified squamous epithelium (SSE) with goblet cells (arrows) (b) Palate-roof ofthe oral cavity epithelium (E) submucosa (SM) with irregular connective tissue adipose tissue (ADP) skeletal muscle (M) and underlyingbone (B) (c) Floor of the oral cavity epithelium (E) laminar muscularis (LM) propria submucosa (PSM) and skeletal muscle (SM) (d)Tongue adipose tissue (arrows) skeletal muscle (SM) connective tissue (CT) and underlying cartilage (C)

335 Stomach The stomach consisted of three distinctregions that were distinguished on the basis of glands in thelamina propria the cardiac fundic and pyloric regions In allthe parts the stomachwas lined by a simple columnar epithe-lium Laminar muscularis was not observed in the stomach

The lamina propria had numerous straight tubular glands(Figure 7(a)) that appeared shorter in the pyloric region ascompared to the fundic and cardiac regions The submucosawas made of loose connective tissue with numerous bloodvessels Tunica muscularis consisted of inner circular and

6 The Scientific World Journal

LM

CMBV

BV

SM LP

25 120583m

Figure 6 Transverse section of esophagus lamina propria (LP)submucosa (SM) blood vessel (BV) inner circular muscle (CM)and outer longitudinal muscle (LM) Arrows tubular glands

outer longitudinal smooth muscle layers (Figure 7(b)) Thelongitudinal muscle layer was slightly thicker in the fundicregion of the stomach The serosa was a single layer ofsquamous cells beneath the muscularis

336 Liver The liver was divided into lobules by connec-tive tissue sheets with a central vein in the middle (Fig-ure 8(a)) The hepatocytes were visible throughout the liverparenchyma arranged close to each other forming irregularcords Throughout the liver lobules were scattered tubularacinar glands of the exocrine pancreas forming the hepat-opancreas and secretory vesicles (Figure 8(b))

337 Intestine Themucosal layer of the intestine was throwninto folds (villi) of varying sizes (Figure 9(a)) Villi weretallest in the anterior part of the intestine The mucosa waslined with a simple columnar epithelium with numerouslymphocytes cell-like infiltrations Numerous goblet cellsthat increased in number towards the anal opening wereseen in the lamina epithelialis The submucosa was thinwith its connective tissue extending the entire length of thevilli Tunica muscularis was made up of inner circular andouter longitudinal layer of smooth muscle (Figure 9(b)) Thehistological organization of the caeca was identical to thatof the anterior and posterior intestine but with less villi andgoblet cells

4 Discussion

Histomorphological studies in fish have increasingly becomeimportant given the growing interest in aquaculture [20]since the structure of the digestive system in fish indicates itsfeeding behaviour and provides insights into feeding strate-gies for cultured fish [21 22] Gross morphological investiga-tions in this study revealed that the oral cavity inA baremoze

LM

CM

SM

LPE

L

50 120583m

(a)

CMSM

LP

50 120583m

(b)

Figure 7 Transverse section through the stomach (a) Cardiacstomach and (b) fundic stomach lumen (L) epithelium (E) sub-mucosa (SM) lamina propria (LP) circular muscle layer (CM) andlongitudinal muscle (LM)

is composed of a small fleshy-lipped terminal mouth withboth conical andmolariformdentitions Similarmouth struc-tures have been observed in Cheilinus lunulatus [23] withmolariform and conical teeth common in Clarias gariepinus[24] Herichthys minckleyi [25] Aphanius persicus [26] andChrysobrycon eliasi [27] Terminal mouths in fish have beenrelated to chasing and capture of small food items [28]while the presence of teeth on the jaws enables the predatorto hold and grasp prey items [29] Similarly conical denti-tions have been associated with soft bodied predators [30]while molariform dentations have been associated with mol-lusc and crustacean feeders [23] The presence of these twodentition types in A baremoze suggests that this fish feeds ona variety of food items but mainly of animal origin Histo-logical investigations further revealed the presence of severalgoblet cells in the epithelium lining the oral cavity severalskeletal muscles adipose tissue and an underlying cartilagein the cavity Similar observations have been reported inOreochromis niloticus and Clarias gariepinus [31] wherepresence of mucus secreting glands was suggested to implysecretion of copious amounts of mucus needed to lubricatethe oral cavity to ease swallowing Meanwhile the presence ofmuscle networks and adipose tissue suggests ease of mouthmovement duringmastication and a cushion of fat cells to actas a shock absorber during food acquisition and swallowing

The Scientific World Journal 7

CV

ExP25 120583m

(a)

SV

ExP

25 120583m

(b)

Figure 8 Liver (a) CV central vein and (b) ExP exocrine pancreas with secretory vesicles (SV) with hepatocytes arranged in irregularcords

LM

V

V

SM

50 120583m

(a)

SM

E

LM SE

50 120583m

(b)

Figure 9 Intestine E epithelium SM submucosa V villi SE serosa and LM longitudinal muscle arrows are goblet cells

The oesophagus in A baremoze in this study is shortand has numerous tubular glands located in the laminapropria The mucosa is also greatly folded while the tunicamuscularis is well developed with inner circular musclesand outer longitudinal skeletal muscles Similar reports havebeen given in other fishes such as Clarias gariepinus andCtenopharyngodon idella [32] All these studies conclude thatthe numerous mucosal folds provide for increased surfacearea for chemical activity Similarly several tubular glandswere also observed in the lamina propria of the oesophagusin A baremoze in this study This therefore suggests thatchemical digestion in A baremoze begins in the oesophagus

Study results reveal the presence of a pouch-like stomachinA baremozewhose lamina propria had numerous straighttubular glands as has been reported in Esox lucius [3334] and Lates niloticus [35] In these fishes the presenceof a pouch-shaped stomach has been related to large feedquantity intake which is slowly digested by chemical sub-stances released from the tubular glands This could be themechanism of digestion also occurring in A baremoze

Morphological observations indicated that the liver inA baremoze is three-lobed and lies adjacent to the oesoph-agus stomach and the anterior section of the intestineHistologically the liver parenchyma contained tubular acinarglands which constituted the exocrine pancreas formingthe hepatopancreas This arrangement is similar to whatwas observed in several fish and freshwater bivalves [1736] However the hepatopancreas is not observed in highervertebrates [37]

Similarly observations made in this study reveal thatA baremoze has a nine-fingered caeca and a long tubularintestine lying alongside the gonadsMultifingered caeca havebeen reported in several other fishes and have been proposedto be important in chemical digestion [38] absorption [39]osmoregulation [40] food storage lipid absorption and opti-mising pH for digestion [41] Histologically the organisationof the intestine did not significantly differ from that of thecaecaThe arrangement of this structure is in agreement withfindings by [42] and is suitable for absorbing digested food[43]

8 The Scientific World Journal

The RGL of A baremoze in this study was 12 plusmn 0085(Table 1) The relationship between RGL and trophic levels infishes has been documented [15]This relationship is believedto reflect the digestive processing time required for differentfood material Herbivorous fish species for instance tend tohave higher RGL compared to omnivorous and carnivorousfishes due to the fibrous plant material they ingest whichrequires longer digestion time Although the RGL varies withfish species and growth stages [16] categorises fish as eithercarnivorous (RGL=06ndash08) omnivorous (RGL=08ndash10) orherbivorous (RGL = 25ndash164)This suggests thatA baremozeis an omnivorous fish a situation confirmed by observationsmade from its stomach contents (Table 2) which were seento cut across plant and animal material According to [1] Abaremoze has a flexible diet shifting from zooplankton tozoobenthos detritus and macrophytes as plankton densitiesdecline Findings reported by [6] on food web structure inLake Albert suggest that ontogenetic shifts occurred in thediet of A baremoze and this was partly driven by structuralchanges in feeding apparatus and morphology that openedup new and unexploited feeding opportunities Similarly sizespecific shifts in food or habitat type have been documentedin many species [44 45] Previous studies related to feedingecology on one of the closest relatives Alestes nurse inthe Alestidae family by [44] indicated that A nurse wasobserved to change its food diet from phytoplankton andsmall zooplankton during their premetamorphosis stages tolarger zooplankton The observed dietary shifts observed inA baremoze suggest that this fish can survive on a variety offood items and this makes it a good aquaculture candidatewith ability to survive on formulated diets given that theseare developed from a variety of raw materials both of planand animal origin

5 Conclusion

Histomorphological observations and stomach content anal-ysis performed in this study suggest that A baremoze hasmorphological adaptations for omnivory The molariformdentation observed in the adult fish also helps them to feed onhard bodied organisms Further investigations to assess theability ofA baremoze to digest formulated diets will be useful

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the grant from the Compet-itive Grant Scheme of the National Agricultural ResearchOrganisation (NARO) under the Agricultural Technologyand Agribusiness Advisory Services (ATAAS) project andwas implemented by Abi Zonal Agricultural Research andDevelopment Institute (Abi ZARDI) CGS Project IDnoCGS43214

References

[1] E Akinyi A Awaıss A Azeroual A Getahun P Laleye andT Twongo ldquoAlestes baremozerdquo in IUCN 2012 IUCN Red List ofThreatened Species Version 20122 2010

[2] DMbabazi M A Taabu L I Muhoozi et al ldquoThe past presentand projected scenarios in the lake Albert and Albert nilefisheries implications for sustainable managementrdquo UgandaJournal of Agricultural Sciences vol 13 no 2 pp 47ndash64 2012

[3] N Kasozi G I Degu K Atibuni M Kisekka A Owori-Wadunde and S Mugerwa ldquoClassification of ovarian stages ofAlestes baremoze (Joannis 1835) a step towards understandingits reproductive biologyrdquo Frontiers in Science vol 3 no 4 pp107ndash113 2013

[4] ldquoNaFIRRI (National Fisheries Resources Research Institute)rdquoCapture fisheries in UgandaTheNile perch fishery Traditionaland Emerging Fisheries Overfishing and the use of illegal gearson Lake Albert Jinja Uganda Policy Brief No 1 2012

[5] M J Holden ldquoThe feeding habits of Alestes baremose andHydrocynus forskali (Pisces) in Lake Albert East AfricardquoJournal of Zoology vol 161 no 1 pp 137ndash144 1970

[6] L M Campbell S B Wandera R J Thacker D G Dixonand R E Hecky ldquoTrophic niche segregation in the Niloticichthyofauna of Lake Albert (Uganda Africa)rdquo EnvironmentalBiology of Fishes vol 74 no 3-4 pp 247ndash260 2005

[7] K L Riley C R Weirich and D Cerino ldquoDevelopment andgrowth of hatchery-reared larval Florida pompano (Trachinotuscarolinus)rdquo Fishery Bulletin vol 107 no 3 pp 318ndash328 2009

[8] I Roslashnnestad M Yufera B Ueberschar L Ribeiro Oslash Saeligleand C Boglione ldquoFeeding behaviour and digestive physiologyin larval fish Current knowledge and gaps and bottlenecks inresearchrdquo Reviews in Aquaculture vol 5 no 1 pp S59ndashS982013

[9] J Abowei and A T Ekubo ldquoSome principles and requirementsin fish nutritionrdquo British Journal of Pharmacology and Toxicol-ogy vol 2 no 4 pp 163ndash178 2011

[10] J Sweetman A Dimitroglou S Davies and S TorrecillasldquoNutrient uptake gut morphology a key to efficient nutritionrdquoInternational Aqua Feed vol 8 pp 26ndash30 2008

[11] R K Buddington A Krogdahl and A M Bakke-MckellepldquoThe intestines of carnivorous fish structure and functionsand the relations with dietrdquo Acta Physiologica ScandinavicaSupplementum no 638 pp 67ndash80 1997

[12] R Hofer ldquoMorphological adaptations of the digestive tract oftropical cyprinids and cichlids to dietrdquo Journal of Fish Biologyvol 33 no 3 pp 399ndash408 1988

[13] C Ribeiro and E Fanta ldquoMicroscopic morphology and histo-chemistry of the digestive system of a tropical freshwater fishTrichomycterus brasiliensis (Lutken) (Siluroidei Trichomycteri-dae)rdquo Revista Brasileira de Zoologia vol 17 no 4 pp 953ndash9712000

[14] W H Karasov C Martınez Del Rio and E Caviedes-VidalldquoEcological physiology of diet and digestive systemsrdquo AnnualReview of Physiology vol 73 pp 69ndash93 2011

[15] B CananW S do Nascimento N B da Silva and S ChellappaldquoMorphohistology of the digestive tract of the damsel fishStegastes fuscus (Osteichthyes Pomacentridae)rdquo The ScientificWorld Journal vol 2012 Article ID 787316 9 pages 2012

[16] D P German andMHHorn ldquoGut length andmass in herbivo-rous and carnivorous prickleback fishes (Teleostei Stichaeidae)Ontogenetic dietary and phylogenetic effectsrdquoMarine Biologyvol 148 no 5 pp 1123ndash1134 2006

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

The Scientific World Journal 5

Table 2 Point assessment percentages of various categories of food items in the stomachs of Alestes baremoze collected from Lake AlbertUganda during the year 2016

Category Food items Point assessment percentages

Insecta

Remains of winged insect 90Dragonflies 80

Ephemeroptera (nymph) 77Adult grasshoppers 745

Mollusca Gastropoda 475

Crustacea

Ostracoda 453Daphnia 27Shrimps 27Cyclops 17Moina 11

Other food items

Detritus 229Phytoplankton (Microcystis and Chlorella) 26

Eggs 258Fish scales 25Small stones 21Round worms 05

SM SSEE

50 120583m

(a)

SM

ADP

ADP

B

M

50 120583m

(b)

E

LM PSM

S

50 120583m

(c)

CT

SM

50 120583m

(d)

Figure 5 Oral cavity (a) Lips skeletal muscles (SM) and stratified squamous epithelium (SSE) with goblet cells (arrows) (b) Palate-roof ofthe oral cavity epithelium (E) submucosa (SM) with irregular connective tissue adipose tissue (ADP) skeletal muscle (M) and underlyingbone (B) (c) Floor of the oral cavity epithelium (E) laminar muscularis (LM) propria submucosa (PSM) and skeletal muscle (SM) (d)Tongue adipose tissue (arrows) skeletal muscle (SM) connective tissue (CT) and underlying cartilage (C)

335 Stomach The stomach consisted of three distinctregions that were distinguished on the basis of glands in thelamina propria the cardiac fundic and pyloric regions In allthe parts the stomachwas lined by a simple columnar epithe-lium Laminar muscularis was not observed in the stomach

The lamina propria had numerous straight tubular glands(Figure 7(a)) that appeared shorter in the pyloric region ascompared to the fundic and cardiac regions The submucosawas made of loose connective tissue with numerous bloodvessels Tunica muscularis consisted of inner circular and

6 The Scientific World Journal

LM

CMBV

BV

SM LP

25 120583m

Figure 6 Transverse section of esophagus lamina propria (LP)submucosa (SM) blood vessel (BV) inner circular muscle (CM)and outer longitudinal muscle (LM) Arrows tubular glands

outer longitudinal smooth muscle layers (Figure 7(b)) Thelongitudinal muscle layer was slightly thicker in the fundicregion of the stomach The serosa was a single layer ofsquamous cells beneath the muscularis

336 Liver The liver was divided into lobules by connec-tive tissue sheets with a central vein in the middle (Fig-ure 8(a)) The hepatocytes were visible throughout the liverparenchyma arranged close to each other forming irregularcords Throughout the liver lobules were scattered tubularacinar glands of the exocrine pancreas forming the hepat-opancreas and secretory vesicles (Figure 8(b))

337 Intestine Themucosal layer of the intestine was throwninto folds (villi) of varying sizes (Figure 9(a)) Villi weretallest in the anterior part of the intestine The mucosa waslined with a simple columnar epithelium with numerouslymphocytes cell-like infiltrations Numerous goblet cellsthat increased in number towards the anal opening wereseen in the lamina epithelialis The submucosa was thinwith its connective tissue extending the entire length of thevilli Tunica muscularis was made up of inner circular andouter longitudinal layer of smooth muscle (Figure 9(b)) Thehistological organization of the caeca was identical to thatof the anterior and posterior intestine but with less villi andgoblet cells

4 Discussion

Histomorphological studies in fish have increasingly becomeimportant given the growing interest in aquaculture [20]since the structure of the digestive system in fish indicates itsfeeding behaviour and provides insights into feeding strate-gies for cultured fish [21 22] Gross morphological investiga-tions in this study revealed that the oral cavity inA baremoze

LM

CM

SM

LPE

L

50 120583m

(a)

CMSM

LP

50 120583m

(b)

Figure 7 Transverse section through the stomach (a) Cardiacstomach and (b) fundic stomach lumen (L) epithelium (E) sub-mucosa (SM) lamina propria (LP) circular muscle layer (CM) andlongitudinal muscle (LM)

is composed of a small fleshy-lipped terminal mouth withboth conical andmolariformdentitions Similarmouth struc-tures have been observed in Cheilinus lunulatus [23] withmolariform and conical teeth common in Clarias gariepinus[24] Herichthys minckleyi [25] Aphanius persicus [26] andChrysobrycon eliasi [27] Terminal mouths in fish have beenrelated to chasing and capture of small food items [28]while the presence of teeth on the jaws enables the predatorto hold and grasp prey items [29] Similarly conical denti-tions have been associated with soft bodied predators [30]while molariform dentations have been associated with mol-lusc and crustacean feeders [23] The presence of these twodentition types in A baremoze suggests that this fish feeds ona variety of food items but mainly of animal origin Histo-logical investigations further revealed the presence of severalgoblet cells in the epithelium lining the oral cavity severalskeletal muscles adipose tissue and an underlying cartilagein the cavity Similar observations have been reported inOreochromis niloticus and Clarias gariepinus [31] wherepresence of mucus secreting glands was suggested to implysecretion of copious amounts of mucus needed to lubricatethe oral cavity to ease swallowing Meanwhile the presence ofmuscle networks and adipose tissue suggests ease of mouthmovement duringmastication and a cushion of fat cells to actas a shock absorber during food acquisition and swallowing

The Scientific World Journal 7

CV

ExP25 120583m

(a)

SV

ExP

25 120583m

(b)

Figure 8 Liver (a) CV central vein and (b) ExP exocrine pancreas with secretory vesicles (SV) with hepatocytes arranged in irregularcords

LM

V

V

SM

50 120583m

(a)

SM

E

LM SE

50 120583m

(b)

Figure 9 Intestine E epithelium SM submucosa V villi SE serosa and LM longitudinal muscle arrows are goblet cells

The oesophagus in A baremoze in this study is shortand has numerous tubular glands located in the laminapropria The mucosa is also greatly folded while the tunicamuscularis is well developed with inner circular musclesand outer longitudinal skeletal muscles Similar reports havebeen given in other fishes such as Clarias gariepinus andCtenopharyngodon idella [32] All these studies conclude thatthe numerous mucosal folds provide for increased surfacearea for chemical activity Similarly several tubular glandswere also observed in the lamina propria of the oesophagusin A baremoze in this study This therefore suggests thatchemical digestion in A baremoze begins in the oesophagus

Study results reveal the presence of a pouch-like stomachinA baremozewhose lamina propria had numerous straighttubular glands as has been reported in Esox lucius [3334] and Lates niloticus [35] In these fishes the presenceof a pouch-shaped stomach has been related to large feedquantity intake which is slowly digested by chemical sub-stances released from the tubular glands This could be themechanism of digestion also occurring in A baremoze

Morphological observations indicated that the liver inA baremoze is three-lobed and lies adjacent to the oesoph-agus stomach and the anterior section of the intestineHistologically the liver parenchyma contained tubular acinarglands which constituted the exocrine pancreas formingthe hepatopancreas This arrangement is similar to whatwas observed in several fish and freshwater bivalves [1736] However the hepatopancreas is not observed in highervertebrates [37]

Similarly observations made in this study reveal thatA baremoze has a nine-fingered caeca and a long tubularintestine lying alongside the gonadsMultifingered caeca havebeen reported in several other fishes and have been proposedto be important in chemical digestion [38] absorption [39]osmoregulation [40] food storage lipid absorption and opti-mising pH for digestion [41] Histologically the organisationof the intestine did not significantly differ from that of thecaecaThe arrangement of this structure is in agreement withfindings by [42] and is suitable for absorbing digested food[43]

8 The Scientific World Journal

The RGL of A baremoze in this study was 12 plusmn 0085(Table 1) The relationship between RGL and trophic levels infishes has been documented [15]This relationship is believedto reflect the digestive processing time required for differentfood material Herbivorous fish species for instance tend tohave higher RGL compared to omnivorous and carnivorousfishes due to the fibrous plant material they ingest whichrequires longer digestion time Although the RGL varies withfish species and growth stages [16] categorises fish as eithercarnivorous (RGL=06ndash08) omnivorous (RGL=08ndash10) orherbivorous (RGL = 25ndash164)This suggests thatA baremozeis an omnivorous fish a situation confirmed by observationsmade from its stomach contents (Table 2) which were seento cut across plant and animal material According to [1] Abaremoze has a flexible diet shifting from zooplankton tozoobenthos detritus and macrophytes as plankton densitiesdecline Findings reported by [6] on food web structure inLake Albert suggest that ontogenetic shifts occurred in thediet of A baremoze and this was partly driven by structuralchanges in feeding apparatus and morphology that openedup new and unexploited feeding opportunities Similarly sizespecific shifts in food or habitat type have been documentedin many species [44 45] Previous studies related to feedingecology on one of the closest relatives Alestes nurse inthe Alestidae family by [44] indicated that A nurse wasobserved to change its food diet from phytoplankton andsmall zooplankton during their premetamorphosis stages tolarger zooplankton The observed dietary shifts observed inA baremoze suggest that this fish can survive on a variety offood items and this makes it a good aquaculture candidatewith ability to survive on formulated diets given that theseare developed from a variety of raw materials both of planand animal origin

5 Conclusion

Histomorphological observations and stomach content anal-ysis performed in this study suggest that A baremoze hasmorphological adaptations for omnivory The molariformdentation observed in the adult fish also helps them to feed onhard bodied organisms Further investigations to assess theability ofA baremoze to digest formulated diets will be useful

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the grant from the Compet-itive Grant Scheme of the National Agricultural ResearchOrganisation (NARO) under the Agricultural Technologyand Agribusiness Advisory Services (ATAAS) project andwas implemented by Abi Zonal Agricultural Research andDevelopment Institute (Abi ZARDI) CGS Project IDnoCGS43214

References

[1] E Akinyi A Awaıss A Azeroual A Getahun P Laleye andT Twongo ldquoAlestes baremozerdquo in IUCN 2012 IUCN Red List ofThreatened Species Version 20122 2010

[2] DMbabazi M A Taabu L I Muhoozi et al ldquoThe past presentand projected scenarios in the lake Albert and Albert nilefisheries implications for sustainable managementrdquo UgandaJournal of Agricultural Sciences vol 13 no 2 pp 47ndash64 2012

[3] N Kasozi G I Degu K Atibuni M Kisekka A Owori-Wadunde and S Mugerwa ldquoClassification of ovarian stages ofAlestes baremoze (Joannis 1835) a step towards understandingits reproductive biologyrdquo Frontiers in Science vol 3 no 4 pp107ndash113 2013

[4] ldquoNaFIRRI (National Fisheries Resources Research Institute)rdquoCapture fisheries in UgandaTheNile perch fishery Traditionaland Emerging Fisheries Overfishing and the use of illegal gearson Lake Albert Jinja Uganda Policy Brief No 1 2012

[5] M J Holden ldquoThe feeding habits of Alestes baremose andHydrocynus forskali (Pisces) in Lake Albert East AfricardquoJournal of Zoology vol 161 no 1 pp 137ndash144 1970

[6] L M Campbell S B Wandera R J Thacker D G Dixonand R E Hecky ldquoTrophic niche segregation in the Niloticichthyofauna of Lake Albert (Uganda Africa)rdquo EnvironmentalBiology of Fishes vol 74 no 3-4 pp 247ndash260 2005

[7] K L Riley C R Weirich and D Cerino ldquoDevelopment andgrowth of hatchery-reared larval Florida pompano (Trachinotuscarolinus)rdquo Fishery Bulletin vol 107 no 3 pp 318ndash328 2009

[8] I Roslashnnestad M Yufera B Ueberschar L Ribeiro Oslash Saeligleand C Boglione ldquoFeeding behaviour and digestive physiologyin larval fish Current knowledge and gaps and bottlenecks inresearchrdquo Reviews in Aquaculture vol 5 no 1 pp S59ndashS982013

[9] J Abowei and A T Ekubo ldquoSome principles and requirementsin fish nutritionrdquo British Journal of Pharmacology and Toxicol-ogy vol 2 no 4 pp 163ndash178 2011

[10] J Sweetman A Dimitroglou S Davies and S TorrecillasldquoNutrient uptake gut morphology a key to efficient nutritionrdquoInternational Aqua Feed vol 8 pp 26ndash30 2008

[11] R K Buddington A Krogdahl and A M Bakke-MckellepldquoThe intestines of carnivorous fish structure and functionsand the relations with dietrdquo Acta Physiologica ScandinavicaSupplementum no 638 pp 67ndash80 1997

[12] R Hofer ldquoMorphological adaptations of the digestive tract oftropical cyprinids and cichlids to dietrdquo Journal of Fish Biologyvol 33 no 3 pp 399ndash408 1988

[13] C Ribeiro and E Fanta ldquoMicroscopic morphology and histo-chemistry of the digestive system of a tropical freshwater fishTrichomycterus brasiliensis (Lutken) (Siluroidei Trichomycteri-dae)rdquo Revista Brasileira de Zoologia vol 17 no 4 pp 953ndash9712000

[14] W H Karasov C Martınez Del Rio and E Caviedes-VidalldquoEcological physiology of diet and digestive systemsrdquo AnnualReview of Physiology vol 73 pp 69ndash93 2011

[15] B CananW S do Nascimento N B da Silva and S ChellappaldquoMorphohistology of the digestive tract of the damsel fishStegastes fuscus (Osteichthyes Pomacentridae)rdquo The ScientificWorld Journal vol 2012 Article ID 787316 9 pages 2012

[16] D P German andMHHorn ldquoGut length andmass in herbivo-rous and carnivorous prickleback fishes (Teleostei Stichaeidae)Ontogenetic dietary and phylogenetic effectsrdquoMarine Biologyvol 148 no 5 pp 1123ndash1134 2006

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

6 The Scientific World Journal

LM

CMBV

BV

SM LP

25 120583m

Figure 6 Transverse section of esophagus lamina propria (LP)submucosa (SM) blood vessel (BV) inner circular muscle (CM)and outer longitudinal muscle (LM) Arrows tubular glands

outer longitudinal smooth muscle layers (Figure 7(b)) Thelongitudinal muscle layer was slightly thicker in the fundicregion of the stomach The serosa was a single layer ofsquamous cells beneath the muscularis

336 Liver The liver was divided into lobules by connec-tive tissue sheets with a central vein in the middle (Fig-ure 8(a)) The hepatocytes were visible throughout the liverparenchyma arranged close to each other forming irregularcords Throughout the liver lobules were scattered tubularacinar glands of the exocrine pancreas forming the hepat-opancreas and secretory vesicles (Figure 8(b))

337 Intestine Themucosal layer of the intestine was throwninto folds (villi) of varying sizes (Figure 9(a)) Villi weretallest in the anterior part of the intestine The mucosa waslined with a simple columnar epithelium with numerouslymphocytes cell-like infiltrations Numerous goblet cellsthat increased in number towards the anal opening wereseen in the lamina epithelialis The submucosa was thinwith its connective tissue extending the entire length of thevilli Tunica muscularis was made up of inner circular andouter longitudinal layer of smooth muscle (Figure 9(b)) Thehistological organization of the caeca was identical to thatof the anterior and posterior intestine but with less villi andgoblet cells

4 Discussion

Histomorphological studies in fish have increasingly becomeimportant given the growing interest in aquaculture [20]since the structure of the digestive system in fish indicates itsfeeding behaviour and provides insights into feeding strate-gies for cultured fish [21 22] Gross morphological investiga-tions in this study revealed that the oral cavity inA baremoze

LM

CM

SM

LPE

L

50 120583m

(a)

CMSM

LP

50 120583m

(b)

Figure 7 Transverse section through the stomach (a) Cardiacstomach and (b) fundic stomach lumen (L) epithelium (E) sub-mucosa (SM) lamina propria (LP) circular muscle layer (CM) andlongitudinal muscle (LM)

is composed of a small fleshy-lipped terminal mouth withboth conical andmolariformdentitions Similarmouth struc-tures have been observed in Cheilinus lunulatus [23] withmolariform and conical teeth common in Clarias gariepinus[24] Herichthys minckleyi [25] Aphanius persicus [26] andChrysobrycon eliasi [27] Terminal mouths in fish have beenrelated to chasing and capture of small food items [28]while the presence of teeth on the jaws enables the predatorto hold and grasp prey items [29] Similarly conical denti-tions have been associated with soft bodied predators [30]while molariform dentations have been associated with mol-lusc and crustacean feeders [23] The presence of these twodentition types in A baremoze suggests that this fish feeds ona variety of food items but mainly of animal origin Histo-logical investigations further revealed the presence of severalgoblet cells in the epithelium lining the oral cavity severalskeletal muscles adipose tissue and an underlying cartilagein the cavity Similar observations have been reported inOreochromis niloticus and Clarias gariepinus [31] wherepresence of mucus secreting glands was suggested to implysecretion of copious amounts of mucus needed to lubricatethe oral cavity to ease swallowing Meanwhile the presence ofmuscle networks and adipose tissue suggests ease of mouthmovement duringmastication and a cushion of fat cells to actas a shock absorber during food acquisition and swallowing

The Scientific World Journal 7

CV

ExP25 120583m

(a)

SV

ExP

25 120583m

(b)

Figure 8 Liver (a) CV central vein and (b) ExP exocrine pancreas with secretory vesicles (SV) with hepatocytes arranged in irregularcords

LM

V

V

SM

50 120583m

(a)

SM

E

LM SE

50 120583m

(b)

Figure 9 Intestine E epithelium SM submucosa V villi SE serosa and LM longitudinal muscle arrows are goblet cells

The oesophagus in A baremoze in this study is shortand has numerous tubular glands located in the laminapropria The mucosa is also greatly folded while the tunicamuscularis is well developed with inner circular musclesand outer longitudinal skeletal muscles Similar reports havebeen given in other fishes such as Clarias gariepinus andCtenopharyngodon idella [32] All these studies conclude thatthe numerous mucosal folds provide for increased surfacearea for chemical activity Similarly several tubular glandswere also observed in the lamina propria of the oesophagusin A baremoze in this study This therefore suggests thatchemical digestion in A baremoze begins in the oesophagus

Study results reveal the presence of a pouch-like stomachinA baremozewhose lamina propria had numerous straighttubular glands as has been reported in Esox lucius [3334] and Lates niloticus [35] In these fishes the presenceof a pouch-shaped stomach has been related to large feedquantity intake which is slowly digested by chemical sub-stances released from the tubular glands This could be themechanism of digestion also occurring in A baremoze

Morphological observations indicated that the liver inA baremoze is three-lobed and lies adjacent to the oesoph-agus stomach and the anterior section of the intestineHistologically the liver parenchyma contained tubular acinarglands which constituted the exocrine pancreas formingthe hepatopancreas This arrangement is similar to whatwas observed in several fish and freshwater bivalves [1736] However the hepatopancreas is not observed in highervertebrates [37]

Similarly observations made in this study reveal thatA baremoze has a nine-fingered caeca and a long tubularintestine lying alongside the gonadsMultifingered caeca havebeen reported in several other fishes and have been proposedto be important in chemical digestion [38] absorption [39]osmoregulation [40] food storage lipid absorption and opti-mising pH for digestion [41] Histologically the organisationof the intestine did not significantly differ from that of thecaecaThe arrangement of this structure is in agreement withfindings by [42] and is suitable for absorbing digested food[43]

8 The Scientific World Journal

The RGL of A baremoze in this study was 12 plusmn 0085(Table 1) The relationship between RGL and trophic levels infishes has been documented [15]This relationship is believedto reflect the digestive processing time required for differentfood material Herbivorous fish species for instance tend tohave higher RGL compared to omnivorous and carnivorousfishes due to the fibrous plant material they ingest whichrequires longer digestion time Although the RGL varies withfish species and growth stages [16] categorises fish as eithercarnivorous (RGL=06ndash08) omnivorous (RGL=08ndash10) orherbivorous (RGL = 25ndash164)This suggests thatA baremozeis an omnivorous fish a situation confirmed by observationsmade from its stomach contents (Table 2) which were seento cut across plant and animal material According to [1] Abaremoze has a flexible diet shifting from zooplankton tozoobenthos detritus and macrophytes as plankton densitiesdecline Findings reported by [6] on food web structure inLake Albert suggest that ontogenetic shifts occurred in thediet of A baremoze and this was partly driven by structuralchanges in feeding apparatus and morphology that openedup new and unexploited feeding opportunities Similarly sizespecific shifts in food or habitat type have been documentedin many species [44 45] Previous studies related to feedingecology on one of the closest relatives Alestes nurse inthe Alestidae family by [44] indicated that A nurse wasobserved to change its food diet from phytoplankton andsmall zooplankton during their premetamorphosis stages tolarger zooplankton The observed dietary shifts observed inA baremoze suggest that this fish can survive on a variety offood items and this makes it a good aquaculture candidatewith ability to survive on formulated diets given that theseare developed from a variety of raw materials both of planand animal origin

5 Conclusion

Histomorphological observations and stomach content anal-ysis performed in this study suggest that A baremoze hasmorphological adaptations for omnivory The molariformdentation observed in the adult fish also helps them to feed onhard bodied organisms Further investigations to assess theability ofA baremoze to digest formulated diets will be useful

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the grant from the Compet-itive Grant Scheme of the National Agricultural ResearchOrganisation (NARO) under the Agricultural Technologyand Agribusiness Advisory Services (ATAAS) project andwas implemented by Abi Zonal Agricultural Research andDevelopment Institute (Abi ZARDI) CGS Project IDnoCGS43214

References

[1] E Akinyi A Awaıss A Azeroual A Getahun P Laleye andT Twongo ldquoAlestes baremozerdquo in IUCN 2012 IUCN Red List ofThreatened Species Version 20122 2010

[2] DMbabazi M A Taabu L I Muhoozi et al ldquoThe past presentand projected scenarios in the lake Albert and Albert nilefisheries implications for sustainable managementrdquo UgandaJournal of Agricultural Sciences vol 13 no 2 pp 47ndash64 2012

[3] N Kasozi G I Degu K Atibuni M Kisekka A Owori-Wadunde and S Mugerwa ldquoClassification of ovarian stages ofAlestes baremoze (Joannis 1835) a step towards understandingits reproductive biologyrdquo Frontiers in Science vol 3 no 4 pp107ndash113 2013

[4] ldquoNaFIRRI (National Fisheries Resources Research Institute)rdquoCapture fisheries in UgandaTheNile perch fishery Traditionaland Emerging Fisheries Overfishing and the use of illegal gearson Lake Albert Jinja Uganda Policy Brief No 1 2012

[5] M J Holden ldquoThe feeding habits of Alestes baremose andHydrocynus forskali (Pisces) in Lake Albert East AfricardquoJournal of Zoology vol 161 no 1 pp 137ndash144 1970

[6] L M Campbell S B Wandera R J Thacker D G Dixonand R E Hecky ldquoTrophic niche segregation in the Niloticichthyofauna of Lake Albert (Uganda Africa)rdquo EnvironmentalBiology of Fishes vol 74 no 3-4 pp 247ndash260 2005

[7] K L Riley C R Weirich and D Cerino ldquoDevelopment andgrowth of hatchery-reared larval Florida pompano (Trachinotuscarolinus)rdquo Fishery Bulletin vol 107 no 3 pp 318ndash328 2009

[8] I Roslashnnestad M Yufera B Ueberschar L Ribeiro Oslash Saeligleand C Boglione ldquoFeeding behaviour and digestive physiologyin larval fish Current knowledge and gaps and bottlenecks inresearchrdquo Reviews in Aquaculture vol 5 no 1 pp S59ndashS982013

[9] J Abowei and A T Ekubo ldquoSome principles and requirementsin fish nutritionrdquo British Journal of Pharmacology and Toxicol-ogy vol 2 no 4 pp 163ndash178 2011

[10] J Sweetman A Dimitroglou S Davies and S TorrecillasldquoNutrient uptake gut morphology a key to efficient nutritionrdquoInternational Aqua Feed vol 8 pp 26ndash30 2008

[11] R K Buddington A Krogdahl and A M Bakke-MckellepldquoThe intestines of carnivorous fish structure and functionsand the relations with dietrdquo Acta Physiologica ScandinavicaSupplementum no 638 pp 67ndash80 1997

[12] R Hofer ldquoMorphological adaptations of the digestive tract oftropical cyprinids and cichlids to dietrdquo Journal of Fish Biologyvol 33 no 3 pp 399ndash408 1988

[13] C Ribeiro and E Fanta ldquoMicroscopic morphology and histo-chemistry of the digestive system of a tropical freshwater fishTrichomycterus brasiliensis (Lutken) (Siluroidei Trichomycteri-dae)rdquo Revista Brasileira de Zoologia vol 17 no 4 pp 953ndash9712000

[14] W H Karasov C Martınez Del Rio and E Caviedes-VidalldquoEcological physiology of diet and digestive systemsrdquo AnnualReview of Physiology vol 73 pp 69ndash93 2011

[15] B CananW S do Nascimento N B da Silva and S ChellappaldquoMorphohistology of the digestive tract of the damsel fishStegastes fuscus (Osteichthyes Pomacentridae)rdquo The ScientificWorld Journal vol 2012 Article ID 787316 9 pages 2012

[16] D P German andMHHorn ldquoGut length andmass in herbivo-rous and carnivorous prickleback fishes (Teleostei Stichaeidae)Ontogenetic dietary and phylogenetic effectsrdquoMarine Biologyvol 148 no 5 pp 1123ndash1134 2006

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

The Scientific World Journal 7

CV

ExP25 120583m

(a)

SV

ExP

25 120583m

(b)

Figure 8 Liver (a) CV central vein and (b) ExP exocrine pancreas with secretory vesicles (SV) with hepatocytes arranged in irregularcords

LM

V

V

SM

50 120583m

(a)

SM

E

LM SE

50 120583m

(b)

Figure 9 Intestine E epithelium SM submucosa V villi SE serosa and LM longitudinal muscle arrows are goblet cells

The oesophagus in A baremoze in this study is shortand has numerous tubular glands located in the laminapropria The mucosa is also greatly folded while the tunicamuscularis is well developed with inner circular musclesand outer longitudinal skeletal muscles Similar reports havebeen given in other fishes such as Clarias gariepinus andCtenopharyngodon idella [32] All these studies conclude thatthe numerous mucosal folds provide for increased surfacearea for chemical activity Similarly several tubular glandswere also observed in the lamina propria of the oesophagusin A baremoze in this study This therefore suggests thatchemical digestion in A baremoze begins in the oesophagus

Study results reveal the presence of a pouch-like stomachinA baremozewhose lamina propria had numerous straighttubular glands as has been reported in Esox lucius [3334] and Lates niloticus [35] In these fishes the presenceof a pouch-shaped stomach has been related to large feedquantity intake which is slowly digested by chemical sub-stances released from the tubular glands This could be themechanism of digestion also occurring in A baremoze

Morphological observations indicated that the liver inA baremoze is three-lobed and lies adjacent to the oesoph-agus stomach and the anterior section of the intestineHistologically the liver parenchyma contained tubular acinarglands which constituted the exocrine pancreas formingthe hepatopancreas This arrangement is similar to whatwas observed in several fish and freshwater bivalves [1736] However the hepatopancreas is not observed in highervertebrates [37]

Similarly observations made in this study reveal thatA baremoze has a nine-fingered caeca and a long tubularintestine lying alongside the gonadsMultifingered caeca havebeen reported in several other fishes and have been proposedto be important in chemical digestion [38] absorption [39]osmoregulation [40] food storage lipid absorption and opti-mising pH for digestion [41] Histologically the organisationof the intestine did not significantly differ from that of thecaecaThe arrangement of this structure is in agreement withfindings by [42] and is suitable for absorbing digested food[43]

8 The Scientific World Journal

The RGL of A baremoze in this study was 12 plusmn 0085(Table 1) The relationship between RGL and trophic levels infishes has been documented [15]This relationship is believedto reflect the digestive processing time required for differentfood material Herbivorous fish species for instance tend tohave higher RGL compared to omnivorous and carnivorousfishes due to the fibrous plant material they ingest whichrequires longer digestion time Although the RGL varies withfish species and growth stages [16] categorises fish as eithercarnivorous (RGL=06ndash08) omnivorous (RGL=08ndash10) orherbivorous (RGL = 25ndash164)This suggests thatA baremozeis an omnivorous fish a situation confirmed by observationsmade from its stomach contents (Table 2) which were seento cut across plant and animal material According to [1] Abaremoze has a flexible diet shifting from zooplankton tozoobenthos detritus and macrophytes as plankton densitiesdecline Findings reported by [6] on food web structure inLake Albert suggest that ontogenetic shifts occurred in thediet of A baremoze and this was partly driven by structuralchanges in feeding apparatus and morphology that openedup new and unexploited feeding opportunities Similarly sizespecific shifts in food or habitat type have been documentedin many species [44 45] Previous studies related to feedingecology on one of the closest relatives Alestes nurse inthe Alestidae family by [44] indicated that A nurse wasobserved to change its food diet from phytoplankton andsmall zooplankton during their premetamorphosis stages tolarger zooplankton The observed dietary shifts observed inA baremoze suggest that this fish can survive on a variety offood items and this makes it a good aquaculture candidatewith ability to survive on formulated diets given that theseare developed from a variety of raw materials both of planand animal origin

5 Conclusion

Histomorphological observations and stomach content anal-ysis performed in this study suggest that A baremoze hasmorphological adaptations for omnivory The molariformdentation observed in the adult fish also helps them to feed onhard bodied organisms Further investigations to assess theability ofA baremoze to digest formulated diets will be useful

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the grant from the Compet-itive Grant Scheme of the National Agricultural ResearchOrganisation (NARO) under the Agricultural Technologyand Agribusiness Advisory Services (ATAAS) project andwas implemented by Abi Zonal Agricultural Research andDevelopment Institute (Abi ZARDI) CGS Project IDnoCGS43214

References

[1] E Akinyi A Awaıss A Azeroual A Getahun P Laleye andT Twongo ldquoAlestes baremozerdquo in IUCN 2012 IUCN Red List ofThreatened Species Version 20122 2010

[2] DMbabazi M A Taabu L I Muhoozi et al ldquoThe past presentand projected scenarios in the lake Albert and Albert nilefisheries implications for sustainable managementrdquo UgandaJournal of Agricultural Sciences vol 13 no 2 pp 47ndash64 2012

[3] N Kasozi G I Degu K Atibuni M Kisekka A Owori-Wadunde and S Mugerwa ldquoClassification of ovarian stages ofAlestes baremoze (Joannis 1835) a step towards understandingits reproductive biologyrdquo Frontiers in Science vol 3 no 4 pp107ndash113 2013

[4] ldquoNaFIRRI (National Fisheries Resources Research Institute)rdquoCapture fisheries in UgandaTheNile perch fishery Traditionaland Emerging Fisheries Overfishing and the use of illegal gearson Lake Albert Jinja Uganda Policy Brief No 1 2012

[5] M J Holden ldquoThe feeding habits of Alestes baremose andHydrocynus forskali (Pisces) in Lake Albert East AfricardquoJournal of Zoology vol 161 no 1 pp 137ndash144 1970

[6] L M Campbell S B Wandera R J Thacker D G Dixonand R E Hecky ldquoTrophic niche segregation in the Niloticichthyofauna of Lake Albert (Uganda Africa)rdquo EnvironmentalBiology of Fishes vol 74 no 3-4 pp 247ndash260 2005

[7] K L Riley C R Weirich and D Cerino ldquoDevelopment andgrowth of hatchery-reared larval Florida pompano (Trachinotuscarolinus)rdquo Fishery Bulletin vol 107 no 3 pp 318ndash328 2009

[8] I Roslashnnestad M Yufera B Ueberschar L Ribeiro Oslash Saeligleand C Boglione ldquoFeeding behaviour and digestive physiologyin larval fish Current knowledge and gaps and bottlenecks inresearchrdquo Reviews in Aquaculture vol 5 no 1 pp S59ndashS982013

[9] J Abowei and A T Ekubo ldquoSome principles and requirementsin fish nutritionrdquo British Journal of Pharmacology and Toxicol-ogy vol 2 no 4 pp 163ndash178 2011

[10] J Sweetman A Dimitroglou S Davies and S TorrecillasldquoNutrient uptake gut morphology a key to efficient nutritionrdquoInternational Aqua Feed vol 8 pp 26ndash30 2008

[11] R K Buddington A Krogdahl and A M Bakke-MckellepldquoThe intestines of carnivorous fish structure and functionsand the relations with dietrdquo Acta Physiologica ScandinavicaSupplementum no 638 pp 67ndash80 1997

[12] R Hofer ldquoMorphological adaptations of the digestive tract oftropical cyprinids and cichlids to dietrdquo Journal of Fish Biologyvol 33 no 3 pp 399ndash408 1988

[13] C Ribeiro and E Fanta ldquoMicroscopic morphology and histo-chemistry of the digestive system of a tropical freshwater fishTrichomycterus brasiliensis (Lutken) (Siluroidei Trichomycteri-dae)rdquo Revista Brasileira de Zoologia vol 17 no 4 pp 953ndash9712000

[14] W H Karasov C Martınez Del Rio and E Caviedes-VidalldquoEcological physiology of diet and digestive systemsrdquo AnnualReview of Physiology vol 73 pp 69ndash93 2011

[15] B CananW S do Nascimento N B da Silva and S ChellappaldquoMorphohistology of the digestive tract of the damsel fishStegastes fuscus (Osteichthyes Pomacentridae)rdquo The ScientificWorld Journal vol 2012 Article ID 787316 9 pages 2012

[16] D P German andMHHorn ldquoGut length andmass in herbivo-rous and carnivorous prickleback fishes (Teleostei Stichaeidae)Ontogenetic dietary and phylogenetic effectsrdquoMarine Biologyvol 148 no 5 pp 1123ndash1134 2006

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

8 The Scientific World Journal

The RGL of A baremoze in this study was 12 plusmn 0085(Table 1) The relationship between RGL and trophic levels infishes has been documented [15]This relationship is believedto reflect the digestive processing time required for differentfood material Herbivorous fish species for instance tend tohave higher RGL compared to omnivorous and carnivorousfishes due to the fibrous plant material they ingest whichrequires longer digestion time Although the RGL varies withfish species and growth stages [16] categorises fish as eithercarnivorous (RGL=06ndash08) omnivorous (RGL=08ndash10) orherbivorous (RGL = 25ndash164)This suggests thatA baremozeis an omnivorous fish a situation confirmed by observationsmade from its stomach contents (Table 2) which were seento cut across plant and animal material According to [1] Abaremoze has a flexible diet shifting from zooplankton tozoobenthos detritus and macrophytes as plankton densitiesdecline Findings reported by [6] on food web structure inLake Albert suggest that ontogenetic shifts occurred in thediet of A baremoze and this was partly driven by structuralchanges in feeding apparatus and morphology that openedup new and unexploited feeding opportunities Similarly sizespecific shifts in food or habitat type have been documentedin many species [44 45] Previous studies related to feedingecology on one of the closest relatives Alestes nurse inthe Alestidae family by [44] indicated that A nurse wasobserved to change its food diet from phytoplankton andsmall zooplankton during their premetamorphosis stages tolarger zooplankton The observed dietary shifts observed inA baremoze suggest that this fish can survive on a variety offood items and this makes it a good aquaculture candidatewith ability to survive on formulated diets given that theseare developed from a variety of raw materials both of planand animal origin

5 Conclusion

Histomorphological observations and stomach content anal-ysis performed in this study suggest that A baremoze hasmorphological adaptations for omnivory The molariformdentation observed in the adult fish also helps them to feed onhard bodied organisms Further investigations to assess theability ofA baremoze to digest formulated diets will be useful

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper

Acknowledgments

This work was supported by the grant from the Compet-itive Grant Scheme of the National Agricultural ResearchOrganisation (NARO) under the Agricultural Technologyand Agribusiness Advisory Services (ATAAS) project andwas implemented by Abi Zonal Agricultural Research andDevelopment Institute (Abi ZARDI) CGS Project IDnoCGS43214

References

[1] E Akinyi A Awaıss A Azeroual A Getahun P Laleye andT Twongo ldquoAlestes baremozerdquo in IUCN 2012 IUCN Red List ofThreatened Species Version 20122 2010

[2] DMbabazi M A Taabu L I Muhoozi et al ldquoThe past presentand projected scenarios in the lake Albert and Albert nilefisheries implications for sustainable managementrdquo UgandaJournal of Agricultural Sciences vol 13 no 2 pp 47ndash64 2012

[3] N Kasozi G I Degu K Atibuni M Kisekka A Owori-Wadunde and S Mugerwa ldquoClassification of ovarian stages ofAlestes baremoze (Joannis 1835) a step towards understandingits reproductive biologyrdquo Frontiers in Science vol 3 no 4 pp107ndash113 2013

[4] ldquoNaFIRRI (National Fisheries Resources Research Institute)rdquoCapture fisheries in UgandaTheNile perch fishery Traditionaland Emerging Fisheries Overfishing and the use of illegal gearson Lake Albert Jinja Uganda Policy Brief No 1 2012

[5] M J Holden ldquoThe feeding habits of Alestes baremose andHydrocynus forskali (Pisces) in Lake Albert East AfricardquoJournal of Zoology vol 161 no 1 pp 137ndash144 1970

[6] L M Campbell S B Wandera R J Thacker D G Dixonand R E Hecky ldquoTrophic niche segregation in the Niloticichthyofauna of Lake Albert (Uganda Africa)rdquo EnvironmentalBiology of Fishes vol 74 no 3-4 pp 247ndash260 2005

[7] K L Riley C R Weirich and D Cerino ldquoDevelopment andgrowth of hatchery-reared larval Florida pompano (Trachinotuscarolinus)rdquo Fishery Bulletin vol 107 no 3 pp 318ndash328 2009

[8] I Roslashnnestad M Yufera B Ueberschar L Ribeiro Oslash Saeligleand C Boglione ldquoFeeding behaviour and digestive physiologyin larval fish Current knowledge and gaps and bottlenecks inresearchrdquo Reviews in Aquaculture vol 5 no 1 pp S59ndashS982013

[9] J Abowei and A T Ekubo ldquoSome principles and requirementsin fish nutritionrdquo British Journal of Pharmacology and Toxicol-ogy vol 2 no 4 pp 163ndash178 2011

[10] J Sweetman A Dimitroglou S Davies and S TorrecillasldquoNutrient uptake gut morphology a key to efficient nutritionrdquoInternational Aqua Feed vol 8 pp 26ndash30 2008

[11] R K Buddington A Krogdahl and A M Bakke-MckellepldquoThe intestines of carnivorous fish structure and functionsand the relations with dietrdquo Acta Physiologica ScandinavicaSupplementum no 638 pp 67ndash80 1997

[12] R Hofer ldquoMorphological adaptations of the digestive tract oftropical cyprinids and cichlids to dietrdquo Journal of Fish Biologyvol 33 no 3 pp 399ndash408 1988

[13] C Ribeiro and E Fanta ldquoMicroscopic morphology and histo-chemistry of the digestive system of a tropical freshwater fishTrichomycterus brasiliensis (Lutken) (Siluroidei Trichomycteri-dae)rdquo Revista Brasileira de Zoologia vol 17 no 4 pp 953ndash9712000

[14] W H Karasov C Martınez Del Rio and E Caviedes-VidalldquoEcological physiology of diet and digestive systemsrdquo AnnualReview of Physiology vol 73 pp 69ndash93 2011

[15] B CananW S do Nascimento N B da Silva and S ChellappaldquoMorphohistology of the digestive tract of the damsel fishStegastes fuscus (Osteichthyes Pomacentridae)rdquo The ScientificWorld Journal vol 2012 Article ID 787316 9 pages 2012

[16] D P German andMHHorn ldquoGut length andmass in herbivo-rous and carnivorous prickleback fishes (Teleostei Stichaeidae)Ontogenetic dietary and phylogenetic effectsrdquoMarine Biologyvol 148 no 5 pp 1123ndash1134 2006

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

The Scientific World Journal 9

[17] P Karachle and K Stergiou ldquoGut length for several marinefish relationships with body length and trophic implicationsrdquoMarine Biodiversity Records vol 3 article e106 2010

[18] A M Davis P J Unmack B J Pusey R G Pearson and DL Morgan ldquoOntogenetic development of intestinal length andrelationships to diet in an Australasian fish family (Teraponti-dae)rdquo BMC Evolutionary Biology vol 13 no 1 article no 532013

[19] T Downie ldquoTheory and Practice of Histological TechniquesEdited by JD Bancroft amp A Stevens Churchill LivingstoneEdinburgh 740 pages m5500rdquoHistopathology vol 17 no 4 pp386-386 1990

[20] N E El-Bakary and H L El-Gammal ldquoComparative histologyhistochemistry and ultrastuctural studies on the proximalintestines of flathead grey mullet (Mugil cephalus) and seabream (Sparus aurata)rdquo World Applied Science Journal vol 8pp 477ndash485 2010

[21] H B N Hynes ldquoThe Food of Fresh-Water Sticklebacks (Gas-terosteus aculeatus and Pygosteus pungitius) with a Review ofMethods Used in Studies of the Food of Fishesrdquo The Journal ofAnimal Ecology vol 19 no 1 p 36 1950

[22] E J Hyslop ldquoStomach contents analysismdasha review of methodsand their applicationrdquo Journal of Fish Biology vol 17 no 4 pp411ndash429 1980

[23] E Ikpegbu1 D N Ezeasor U C Nlebedum and O NnadozieldquoObservations on the oesogaster of the domesticated africancatfish (Clarias gariepinus Burchell 1822)rdquo Bulgarian Journal ofVeterinary Medicine vol 16 no 2 pp 88ndash95 2013

[24] P CWainwright and B A Richard ldquoPredicting patterns of preyuse frommorphology of fishesrdquoEnvironmental Biology of Fishesvol 44 no 1-3 pp 97ndash113 1995

[25] S A Lakshmi ldquoInterrelationship between the alimentary tractfood and feeding habits of plueronectiform fishes of southeastcoast of Indiardquo Journal of Experimental Sciences vol 1 no 6 pp1ndash7 2010

[26] M M Hassan and A Khalaf ldquoMorphological adaptations ofdigestive tract according to food and feeding habits of thebroomtail wrasse Cheilinus lunulatusrdquo Egyptian Journal ofAquatic Biology and Fisheries vol 17 no 1 pp 123ndash141 2013

[27] A M Gamal E H Elsheikh and E S Nasr ldquoMorphologicaladaptation of the buccal cavity in relation to feeding habitsof the omnivorous fish Clarias gariepinus a scanning electronmicroscopic studyrdquo Journal of Basic amp Applied Zoology vol 65no 3 pp 191ndash198 2012

[28] C D Hulsey J Marks D A Hendrickson C A WilliamsonA E Cohen and M J Stephens ldquoFeeding specialization inHerichthys minckleyi A trophically polymorphic fishrdquo Journalof Fish Biology vol 68 no 5 pp 1399ndash1410 2006

[29] M Monsefi Z Gholami and H Esmaeili ldquoHistological andmorphological studies of digestive tube and liver of the persiantooth-carp Aphanius persicus (Actinopterygii cyprinodonti-dae)rdquo Journal of Biology vol 69 no 1 pp 157ndash164 2010

[30] J A Vanegas-Rıos M D L M Azpelicueta and H OrtegaldquoChrysobrycon eliasi new species of stevardiine fish (Characi-formes Characidae) from the rıo madre de dios and upper rıomanuripe basins PerurdquoNeotropical Ichthyology vol 9 no 4 pp731ndash740 2011

[31] R Fugi A A Agostinho andN S Hahn ldquoTrophicmorphologyof five benthic-feeding fish species of a tropical floodplainrdquoRevista Brasileira de Biologia vol 61 no 1 pp 27ndash33 2001

[32] S Chattopadhyay S Nandi and S K Saikia ldquoMouthmorphom-etry and architecture of freshwater catfishMystus vittatus Bloch

(1974) (Siluriformes Bagridae) in relation to its feeding habitrdquoJournal of Scientific Research vol 6 no 1 pp 169ndash174 2014

[33] E H Elsheikh ldquoScanning electron microscopic studies of gillarches and rakers in relation to feeding habits of some freshwater fishesrdquo Journal of Basic amp Applied Zoology vol 66 pp121ndash130 2013

[34] A S Awaad U K Moawad and M G Tawfiek ldquoComparativehistomorphological and histochemical studies on the oesoph-agus of nile Tilapia Oreochromis niloticus and african catfishClarias gariepinusrdquo Journal of Histology vol 2014 Article ID987041 10 pages 2014

[35] E A Abd El Hafez D M Mokhtar A S Abou-Elhamd andS H AhmedHassan ldquoComparative histomorphological studieson oesophagus of catfish and grass carprdquo Journal of Histologyvol 2013 Article ID 858674 p 10 2013

[36] D Bucke ldquoThe anatomy and histology of the alimentary tractof the carnivorous fish the pike Esox lucius Lrdquo Journal of FishBiology vol 3 no 4 pp 421ndash431 1971

[37] L J Chapman W C Mackay and C W Wilkinson ldquoFeedingflexibility in northern pike (Esox lucius) fish versus invertebratepreyrdquo Canadian Journal of Fisheries and Aquatic Sciences vol46 no 4 pp 666ndash669 1989

[38] V T Namulawa C D Kato E Nyatia P Britz and J RutaisireldquoHistomorphological description of the digestive system of nileperch (L niloticus)rdquo International Journal of Morphology vol29 no 3 pp 723ndash732 2011

[39] A V Andhale P A Bhosale and S P Zambare ldquoHistopatholog-ical study of nickel induced alterations in the freshwater bivalveLammellidens marginalisrdquo Journal of Experimental Sciences vol2 no 4 pp 1ndash3 2011

[40] D E Malarkey K Johnson L Ryan G Boorman and RR Maronpot ldquoNew insights into functional aspects of livermorphologyrdquo Toxicologic Pathology vol 33 no 1 pp 27ndash342005

[41] S Khantaphant and S Benjakul ldquoComparative study on theproteases from fish pyloric caeca and the use for productionof gelatin hydrolysate with antioxidative activityrdquo ComparativeBiochemistry and Physiology - B Biochemistry and MolecularBiology vol 151 no 4 pp 410ndash419 2008

[42] S H Sugiura and R P Ferraris ldquoContributions of differentNaPicotransporter isoforms to dietary regulation of P transport inthe pyloric caeca and intestine of rainbow troutrdquo Journal ofExperimental Biology vol 207 no 12 pp 2055ndash2064 2004

[43] P A Veillette R J White J L Specker and G YoungldquoOsmoregulatory physiology of pyloric ceca Regulated andadaptive changes in chinook salmonrdquo Journal of ExperimentalZoology Part A Comparative Experimental Biology vol 303 no7 pp 608ndash613 2005

[44] F S Rios A L Kalinin M N Fernandes and F T RantinldquoChanges in gut gross morphology of traıra Hoplias malabar-icus (Teleostei Erythrinidae) during long-term starvation andafter refeedingrdquo Brazilian Journal of Biology vol 64 no 3B pp683ndash689 2004

[45] T Ba-Omar V Reginald and D Tobias ldquoSome aspects of theanatomy and histology of digestive tracts in two sympatricspecies of freshwater fishesrdquo Science and Technology vol 8 pp97ndash106 2003

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Anatomy Research International

PeptidesInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporation httpwwwhindawicom

International Journal of

Volume 201

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Molecular Biology International

GenomicsInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioinformaticsAdvances in

Marine BiologyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Signal TransductionJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

Evolutionary BiologyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Biochemistry Research International

ArchaeaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Genetics Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Virolog y

Hindawi Publishing Corporationhttpwwwhindawicom

Nucleic AcidsJournal of

Volume 2014

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Enzyme Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Microbiology