11
Development of a New Type of Fish Diet, Non-Fish Meal Extruded-Pellet Noriko ISHIDA *1 , Tomohiko KOSHIISHI *2 , Tatsuo TSUZAKI *3 , Koji MAENO *4 , Satoshi KATAYAMA *5 , Minoru SATOH *5 , and Shuichi SATOH *6 Abstract: We developed a non-fish meal diet using plant and/or animal protein materials. Three kinds of non-fish meal diets and a control diet containing 50% fish meal were processed. In the non- fish meal diets, the fish meal was replaced with commercially available plant or animal materials and supplemented with taurine and materials for maintaining palatability. These diets were fed to one year old yellowtail (BW 753±96g) in net cages. There was no difference in growth, daily weight gain, daily feeding rate, feed conversion ratio and protein efficiency ratio among the diets. Non-fish meal diets were processed in a factory and dietary properties were studied such as uptake, stomach evacuation rate, and comparative disease resistance in fish fed the experimental diets. In addition, palatability of each substitute protein material for fish was examined and materials to enhance palatability of the non-fish meal diets were clarified. Non-fish meal diets have the potential to support the growth of one year old yellowtail. Key word: Fish diet, Non-fish meal, Extruded-pellet, Yellowtail, Palatability, Substitute protein material In Japan, fish meal is the main material in fish diets used in aquaculture and is contained at a level of over 50%. Over 90% of the fish meal used in fish diets for aquaculture is imported. Globally, the price of fish meal has increased dramatically in recent years due to reduced production caused by fishery regulation in South America and the increased worldwide demand for aquacultured fish. The increasing fish meal price threatens of the viability of production for Japanese aquaculture farmers. Therefore, a new type of diet that is independent of fish meal is strongly required. Low or non-fish meal extruded-pellets have been developed. In our preliminary study, we prepared diets containing 10% fish meal, and fed them to cultured yellowtail to compare the fish growth performances to a diet containing 50% fish meal. It was observed that fish growth was similar in both diet groups. Three experimental non-fish meal extruded-pellets were designed and fed to one year old yellowtail which were at an immature and rapidly growing size. We also studied dietary, uptake, stomach evacuate rate, palatability, and comparative disease resistance of fish. Then the meat quality fed the experimental diets was evaluated using a panel sensory test. Materials and Methods Experimental diets and processing: The control diet and three kinds of non-fish meal diets were prepared using a variety of ingredients (Table 1) (Tsuzaki et al., 2013 and 2014). The control diet (FM) contained 50% fish meal to provide a suitable balance of amino acids. Fish meal was replaced with commercially available plant (PP) and animal (AP) materials in the non-fish meal diets. Soy protein concentrate, defatted soy bean meal, and corn gluten meal were used for plant materials and pork meal, feather 2015年 1 月30日受理(Received on January 30, 2015) *1 National Research Institute of Fisheries Science, FRA, Yokohama 236-8648, Japan E-mail: larry@affrc.go.jp *2 Marubeni Nisshin Feed Co., Ltd., Aichi 441-3605, Japan *3 National Research Institute of Fisheries and Environment of Inland Sea, FRA, Ehime 794-2305, Japan *4 Kagoshima Prefectural Fisheries Technology and Development Center, Kagoshima 891-0315, Japan *5 Tohoku University, Sendai 981-8555, Japan *6 Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan 水研センター研報,第40号,39-49,平成27年 Bull. Fish. Res. Agen. No. 40,39-49,2015 39

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Page 1: Development of a New Type of Fish Diet, Non-Fish … › bulletin › bull › bull40 › 40-02...Key word: Fish diet, Non-fish meal, Extruded-pellet, Yellowtail, Palatability, Substitute

Development of a New Type of Fish Diet, Non-Fish Meal Extruded-Pellet

NorikoISHIDA*1,TomohikoKOSHIISHI*2,TatsuoTSUZAKI*3,KojiMAENO*4, SatoshiKATAYAMA*5,MinoruSATOH*5,andShuichiSATOH*6

Abstract:Wedevelopedanon-fishmealdietusingplantand/oranimalproteinmaterials.Threekindsofnon-fishmealdietsandacontroldietcontaining50%fishmealwereprocessed.Inthenon-fishmealdiets,thefishmealwasreplacedwithcommerciallyavailableplantoranimalmaterialsandsupplementedwithtaurineandmaterials formaintainingpalatability.Thesedietswere fedtooneyearoldyellowtail (BW753±96g) innetcages.Therewasnodifference ingrowth,dailyweightgain,dailyfeedingrate,feedconversionratioandproteinefficiencyratioamongthediets.Non-fishmealdietswereprocessed ina factoryanddietarypropertieswerestudiedsuchasuptake,stomachevacuationrate,andcomparativediseaseresistanceinfishfedtheexperimentaldiets. Inaddition,palatabilityof each substituteproteinmaterial for fishwasexaminedandmaterialstoenhancepalatabilityofthenon-fishmealdietswereclarified.Non-fishmealdietshavethepotentialtosupportthegrowthofoneyearoldyellowtail.

Key word:Fishdiet,Non-fishmeal,Extruded-pellet,Yellowtail,Palatability,Substituteproteinmaterial

 InJapan, fishmeal is themainmaterial in fishdietsusedinaquacultureandiscontainedatalevelofover50%.Over90%ofthefishmealusedinfishdietsforaquacultureisimported.Globally,thepriceof fishmealhas increaseddramatically in recentyearsduetoreducedproductioncausedbyfisheryregulation in SouthAmerica and the increasedworldwide demand for aquacultured fish. Theincreasingfishmealpricethreatensof theviabilityof production for Japanese aquaculture farmers.Therefore, anewtypeofdiet that is independentof fishmeal is strongly required.Lowornon-fishmealextruded-pelletshavebeendeveloped. Inourpreliminary study,weprepareddiets containing10%fishmeal,and fed themtoculturedyellowtailtocomparethefishgrowthperformancestoadietcontaining 50% fishmeal. Itwas observed thatfishgrowthwassimilar inbothdietgroups.Threeexperimentalnon-fishmeal extruded-pelletswere

designedand fed tooneyearoldyellowtailwhichwereatanimmatureandrapidlygrowingsize.Wealsostudieddietary,uptake,stomachevacuaterate,palatability, andcomparativediseaseresistanceoffish.Then themeatquality fed theexperimentaldietswasevaluatedusingapanelsensorytest.

Materials and Methods

Experimental diets and processing:Thecontroldietandthreekindsofnon-fishmealdietswerepreparedusingavarietyof ingredients (Table1) (Tsuzakiet al., 2013and2014).Thecontroldiet(FM)contained50%fishmealtoprovideasuitablebalanceofaminoacids.Fishmealwas replacedwith commerciallyavailableplant (PP) andanimal (AP)materials inthenon-fishmeal diets. Soyprotein concentrate,defattedsoybeanmeal,andcornglutenmealwereused for plantmaterials andporkmeal, feather

2015年 1 月30日受理(ReceivedonJanuary30, 2015)*1 NationalResearchInstituteofFisheriesScience,FRA,Yokohama236-8648,Japan E-mail:[email protected]*2 MarubeniNisshinFeedCo.,Ltd.,Aichi441-3605,Japan*3 NationalResearchInstituteofFisheriesandEnvironmentofInlandSea,FRA,Ehime794-2305,Japan*4 KagoshimaPrefecturalFisheriesTechnologyandDevelopmentCenter,Kagoshima891-0315,Japan*5 TohokuUniversity,Sendai981-8555,Japan*6 TokyoUniversityofMarineScienceandTechnology,Tokyo108-8477,Japan

水研センター研報,第40号,39-49,平成27年Bull.Fish.Res.Agen.No. 40,39-49,2015

39

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Noriko ISHIDA, Tomohiko KOSHIISHI, Tatsuo TSUZAKI, Koji MAENO, Satoshi KATAYAMA, Minoru SATOH, and Shuichi SATOH

Ingredient FM PP-SP PP-FS AP-SPFish meal 1 50.0 0 0 0Soy bean concentrate 2 0 30.0 30.0 0Defatted soy bean meal 3 3.5 11.0 11.0 8.0Corn gluten meal 4 0 12.0 12.0 9.0Krill meal 0 3.0 3.0 3.0Pork meal 5 0 0 0 30.0Feather meal 5 0 0 0 3.0Blood meal 6 0 0 0 3.0Fish oil 7 15.4 17.0 17.0 14.0Wheat 13.0 10.8 10.8 12.0Defatted rice brain 8 8.5 0 0 1.8Tapioca starch 9 6.6 8.0 8.0 8.0Vitamin mixture 10 2.0 2.0 2.0 2.0Mineral mixture 10 1.0 1.0 1.0 1.0Taurine 0 1.0 1.0 1.0Amino acid mixture 11 0 2.2 2.2 2.2Calcium phosphate 12 0 2.0 2.0 2.0Enzyme mixture 13 (external addition) 0 (0.2) (0.2) (0.2)Skipjack peptide 14 (external addition) 0 (0.5) 0 (0.5)Fish sauce 15 (external addition) 0 0 (0.5) 0

10 See Takagi et al. (2005).

Table 1. Formulation of the experimental diets (%)

Diet group

1 Fish meal was made from anchovy meal as the main raw material, imported from Peru.2 Soycomil; Archer Daniels Midland Japan Ltd.3 Nisshin Oillio Co., Ltd.4 Japan Corn Starch Co., Ltd.5 Kagoshima Pure Foods Co., Ltd.6 APC Japan Co., Ltd.7 Tsuji Oil Mills Co., Ltd.8 Suzuki Oil Mills Co., Ltd.9 Sanguan Wongse Industries Co., Ltd.

11 See Aoki et al.(2000b).12 Onoda Chemical Industry Co., Ltd.13 Alltech.14 Marubeni Nisshin Feed Co., Ltd.15 Sakaiovex Co., Ltd.

Table 1.Formulationoftheexperimentaldiets(%)

40

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Non-Fish Meal Extruded-Pellet

meal,andbloodmealwereusedforanimalmaterialsin this study.Taurinewas added to thenon-fishmealdietsata1%composition.Experimentaldietswerecarefully shapedusinganextruder tohavesuitablephysicalpropertiesintheseaandsinkatanappropriaterateratherthanfloat. It i s known that ye l lowta i l become lessresponsive to a diet as the amount of fishmealincluded is reduced (Aokiet al., 2000aand2000b).Therefore, two commercially availablematerials,askipjackpeptide (SP)anda fishsauce (FS)weresupplementedtomaintainthepalatabilityofthenon-fishmealdiet.Theskipjackpeptideisconcentratedfromthecookingwaterofskipjack.Thefishsauceismade frommackerelgutusingapatent-pendingmethod for rapidproduction.Anenzymesolutionandaminoacidchelatedtracemetalswereaddedtothenon-fishmealdiets to improvedigestibilityandabsorption.Thesepalatabilitymaterialsandenzymesolutionwereaddedbya spraymethodafter theextruderprocessingtominimizethevolume(Fig. 1). Therefore, the threekindsofnon-fishmealdietswereasfollows:  PP-SPwas a plant protein based dietwith

theskipjackpeptideasamaterial toenhancepalatability.

  PP-FSwasaplantproteinbaseddietwiththefishsauceasamaterialtoenhancepalatability.

  AP-SPwasananimalproteinbaseddietwiththeskipjackpeptideasamaterial toenhancepalatability.

 Twosizesofexperimentaldiets, 13mmand15mmgraindiameter,werepreparedat theKagoshimaplant ofMarubeniNisshinFeedCo., Ltd.Therewereminimaldifferencesinthegeneralcomposition

amongthefourexperimentaldiets.Smalldifferenceswereseeninthefattyacidcomposition.AP-SPhad16%ofn-3PUFAwhiletheotherdietsrangedfrom22-27%.AP-SP also had 41% of totalmonoenes,higher than the 30-35% found in the otherdiets(Table2). Feeding experiment:Oneyearoldyellowtailswhichoriginated fromseedlingproduction inGotoIsland,NagasakiPrefecturewereused in theexperiments(Tsuzaki et al., 2013and2014).Theaveragebodyweight of 220 fishwas 753±96g.Fourgroups of55fish feddifferentexperimentaldiets tosatiationthree times aweek for sixmonths from July toJanuarywerereared in four4mx4mreplicatenet cages on the sea surface.After January fishcontinued tobe fedwith the leftoverexperimentdietuntilMarch. The feeding experimentwasdivided into twoperiods, summer season (July toSeptember) andautumnseason(OctobertoDecember).Samplingandanalysiswereperformedforeachperiod. Body weight and fork length were monthlymeasuredfor20-25 livefishatrandomfromeverygroup. At theendof theexperiment,all the fishweresampledandweighedandthe followingdataweremeasuredorcalculated.  Conditionfactor=(W/FL3)×103

  Weightgainratio (%) = (TWt + SDW-TW0)/TW0×100

  Dailyweightgainratio(%/day)=(TWt+SDW-TW0)/[(TWt+SDW+TW0)/2×t]×100

  Daily feedingrate (%/day)=F/[(TWt+SDW+TW0)/2×t]×100

  Feedconversionratio(FCR)=F/(TWt+SDW-TW0)

  Proteinefficiencyratio (PER)= (TWt+SDW-TW0)/P

  W:Bodyweight(g)  FL:Forklength(cm)  TW0:Initialtotalbodyweight(g)  TWt:Finaltotalbodyweight(g)  SDW:Totalbodyweight of sampled fishand

deadfish(g)  Nt:Numberoffinalfish  F:Totalfeedintake(g)  t:Rearingdays

Fig. 1.Method to addpalatabilitymaterials andenzymesolutiontofishpellets.Rightissprayedafterbeingshapedtoreducethematerialvolume.Leftisshapedafterblendingallthematerials.

Cross-section Cross-section

SprayBlend with materials

41

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Noriko ISHIDA, Tomohiko KOSHIISHI, Tatsuo TSUZAKI, Koji MAENO, Satoshi KATAYAMA, Minoru SATOH, and Shuichi SATOH

Analysis FM PP-SP PP-FS AP-SP

Moisture 7.6 7.7 8.8 4.9Crude ash 9.1 5.6 5.6 7.4Crude protein 39.8 38.1 37.4 42.0Crude lipid 18.9 16.1 17.4 17.6

Phosphorus contentP (mg/g) 15.4 9.7 9.7 13.4

Fatty acid composition (%)14: 0*1 4.8 4.2 4.3 5.416: 0 18.3 16.5 18.3 15.818: 0 3.8 3.5 4.1 4.2

16: 1n-7 5.8 5.2 5.5 5.518: 1n-9 16.0 16.8 19.0 16.420: 1n-9 2.6 2.7 4.5 7.520: 1n-11 2.2 2.3 1.5 1.522: 1n-11 4.0 4.1 4.5 9.8

18: 2n-6 4.5 7.0 7.1 5.620: 4n-6 1.0 0.9 0.9 0.4

18: 3n-3*2 1.0 1.2 1.1 0.918:4n-3 1.8 1.5 1.3 2.020: 4n-3 0.6 0.6 0.6 0.620: 5n-3 (EPA) 8.0 6.8 6.0 5.222: 5n-3 (DPA) 2.0 1.9 1.9 1.022: 6n-3 (DHA) 13.5 13.6 11.3 6.2Others 10.2 11.1 8.0 12.2n-3 HUFA 25.9 24.3 21.2 14.9

*2 “n-3”represents the omega-3 fatty acid.

n-3 HUFA=18: 4n-3+20: 4n-3+EPA+DPA+DHA.Experimental diets are shown in Table 1.

Table2. Proximate composition,phosphorus content, and fatty acid composition ofthe experimental diets

*1 Left figure represents the number of carbonatoms and right figure after colonrepresents the number of carbon unsaturated bonds.

Proximate composition (%)

Diet group

Table 2. Proximate composition, phosphorus content, and fatty acid composition of theexperimentaldiets

42

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Non-Fish Meal Extruded-Pellet

  P:Totalproteinintake(g) Blood,muscle, and liver sampleswerecollectedfrom5fish ineverygroupatthestart (initial), latesummer (intermediate),and lateautumn (end).Theratioofliverweightperbodyweightwascalculated.Hematocritvalueandplasmacomponentlevelswereanalyzed.Generalcontent,phosphoruscontent,fattyacid composition, and amino acid composition ofmusclewereanalyzed. ThestatisticaldifferencesbetweentrialdietsweredeterminedbyTukey’smultiplerangecomparisontest(p<0.05). Experimental diet uptake, stomach evacuate rate, and comparative disease resistance of fish fed experimental diets : Nutritional absorption wasanalyzedfromfishfecescollectedfromfishrearedinaconicaltank(Fig. 2)usingspecialdietscontainingchromeoxideasaninternalstandardmaterial(Satohet al., 2013). Fishwereanesthetizedandadministeredthediet

at 2%of bodyweight directly into the stomach.Stomach residuewas analyzed over timeby theKjeldahlnitrogenmethodandstomachevacuationratewasestimated(Tohataet al., 2012). Disease resistance was carried out usingStreptococcus dysgalactiae,aninfectiousstreptococcalbacterium.Fishwererearedoneachdiet in indoortanksfor3monthsandfedthebacterium-containingfeedfor5days.Fishmortalitywasobservedovera40dayperiod(Ishidaet al., 2013). Diet palatability:Fishbehaviorwasdividedintofiveresponses afterplacing thediets into a fish tankdescribedasrecognition,ingestion,orientationwithinthemouth,swallowing,orspittingout (Fig. 3).Theactionswereanalyzedbyusingacameratofilmredseabream,yellowtail,andcohosalmonusingsingledrypelletsmade fromonly onematerial (Fig. 4) (Niinumaet al., 2012,Yamauchiet al., 2012).Meat quality of raw sashimi:Apaneltestusingtheordermethod,color-differencemeteranalysis, andelectronicnosesystemanalysiswereperformedforeachexperimentalfishfedPP-SP,PP-FS,AP-SP,andcontroldiet(Tohataet al., 2013).

RESULTS

Processing:Alltheexperimentaldietswereprocessedusingadouble-screwextruder.Atthebeginning intheautumnseason,plantproteinbaseddietsdidnotsinkatasuitablerateandflowedout fromthenetcagecompared to theotherdiets.Therefore thesedietswerere-made.Palatability ingredientsandanenzymesolutionweresprayedontodietstominimizematerialsusedto0.05%fromtheoriginal2%requiredintheblendingmethod(Fig. 1).Growth performances and biological indices in yellowtail:Thegrowthperformances inboth thesummerandautumnperiodareshowninTable3. In the summer per i od when the wate rtemperaturewas 22.8 - 29.2 ℃ all diet groups

Fig. 2.Theconicaltankusedtocollectfecesoffishfed the experimentaldiets to analyzenutritionalabsorption.Right:Fecesatthebottomofthetank

Fig. 3.Fishbehaviorsforthediet.

Waiting Recognition Orientationwithin the mouth

Ingestion Swallowing

Spitting out

43

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Noriko ISHIDA, Tomohiko KOSHIISHI, Tatsuo TSUZAKI, Koji MAENO, Satoshi KATAYAMA, Minoru SATOH, and Shuichi SATOH

showedasimilartotalfeedintakerangingfrom113to118kgandasimilarbodyweightgain (Fig. 5).Intheautumnperiodwhenthewatertemperaturewas11.5 ℃lowerthanduringthesummerperiodtotal food intakeofallgroupswas less than in thesummer ranging from90 to 103kg.No seasonaldifference inweight gainwas seen among dietgroups.

Fig. 4.Behavioralanalysisoffishafterfeedingthediets.

Diet

Filming

Red sea bream, yellowtail, coho salmon

Table 3.Growthperformanceandfeedutilizationbyyellowtailfedtheexperimentaldiets

 Final fork lengthandbodyweightwere48.4cmand2,242g in thecontrol (FM), 48.6cmand2,178g in thePP-SP, 49.0cmand2,234g in thePP-SF,and48.5cmand2,205g in theAP-SP.Differencesbetweencontrol andnon-fishmealdietswerenotobserved and the growthwas almost the same.Therewasno seasonal difference betweendailyweightgain(%/day),dailyfeedingrate(%/day),and

Rearingseason(days)Initial

Summer(90days) Autumn(91days)FM PP-SP PP-FS AP-SP FM PP-SP PP-FS AP-SP

Numberoffish 220*1

Dead 0 0 1 2 1 0 1 1Sampled 3 4 3 4 7 7 7 7Final 52 51 51 49 44 44 43 41

Totalfoodintake(kg) - 113.0 113.9 113.6 118.0 98.5 102.9 101.0 90.5

Bodyweight(g)*2 753±96Final 1663±204a 1700±221a 1698±156a 1688±204a 2242±333a 2178±285a 2234±244a 2205±222a

Forklength(cm)*2 36.9±1.5Final 44.8±2.3a 44.8±1.8a 45.0±1.2a 44.1±1.2a 48.4±2.2a 48.6±1.8a 49.0±1.7a 48.5±1.5a

Conditionfactor*2 15.0±0.8Final 18.3±1.1b 18.8±0.9b 18.6±0.7b 19.7±1.4a 19.6±1.2a 18.9±1.2b 19.0±1.1ab 19.3±1.0ab

Weightgainratio(%)*3 - 116.4 119.9 119.1 113.6 34.2 30.4 31.0 32.3Dailyweightgain(%/day)*3 - 0.82 0.83 0.83 0.80 0.32 0.29 0.30 0.31Dailyfeedingrate(%/day)*3 - 1.92 1.91 2.02 1.91 1.08 1.15 1.05   1.12Feedconversionratio*3 - 2.35 2.29 2.30 2.51 3.33 3.91 3.76 3.39Proteinefficiencyratio*3 - 1.07 1.14 1.16 0.94 0.75 0.67 0.71 0.70*1Fishesweredividedinto4dietgroups,eachgroupcontains55fishes.*2Dataareshownasmean±standarddeviation(n=20-44).Valueshavingdifferentsuperscriptlettersaresignificantlydifferent(P<0.05).*3Showninthetext.ExperimentaldietsareshowninTable1.

44

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Non-Fish Meal Extruded-Pellet

weightgainratio (%).Forexample, feedconversionratio in theautumnseasonwas3.33 in thecontrol(FM)and3.91 inPP-SP, 3.76 inPP-FS,and3.39 inAP-SP. Table4showstheresultsofthebiologicalindicesofculturedfish(n=5).Thelivertobodyweightratioin everygroupwas 1.2 to 1.3 andno significantdifferencewasseen.Theaveragehematocritvalueof 5 fish ineverygroupwas46.2 to50.6withnosignificantdifferenceobserved.Therewere three,two,andonemortalitiesoffishinAP-SP,PP-FS,andFMrespectively.Greenliver,whichisthoughttobeasignoftaurinedeficiency(Takagiet al., 2005),was

Fig. 5. Growth curves of yellowtail fed theexperimentalfishmealdiet(FM: ● )andnon-fishmealdiet (PP-SP: ○ ,PP-FS: ○ ,andAP–SP:△ )innetcagesfor6months.Experimentaldiets

aredetailedinTable1.

0

500

1,000

1,500

2,000

2,500

Aver

age

body

wei

ght (

g)

Aug Oct Dec Jan

Aver

age

body

wei

ght (

g)

MonthJul Sep Nov

Table 4.Changes inhepatosomatic index,heamatocritvalue,andhematochemicalcharacteristics inyellowtail(n=5)fedtheexperimentaldeits

notseeninanyofthedeadfish.  Plasmacomponentsmeasured includedglucose,totalprotein, total cholesterol,glutamatepyruvatetransaminase(GPL),andalkalinephosphatase(ALP).No significantdifferencewasobserved inplasmacomponentsbetweenthetreatmentsinthesummerperiod.Total cholesterol exhibited a significantseasonalvariabilitybetween the treatmentswithlowervaluesof246and266mg/dlinPP-SPandPP-FSrespectively(p<0.05) (Table4).Characteristics such as uptake, stomach evacuate rate, and disease resistance of fish fed the experimental diets:Theuptakeofproteinfromnon-fishmealdietswasreducedby4-9 %comparedtotheFMcontrol(Satohet al., 2013). Evacuation of feed from fish stomachs wasobservedforallthreediets.TheorderoftherateofevacuationwasPP-SP>AP-SP≈FM(Fig. 6). Survivalrateat42daysafter thechallengetestwas80%inFMgroup,and95%inPP-SPandAP-SPgroup(Ishidaet al., 2013).Diet palatability:Fishspittingout feedwasalmostzero for singledry fishmealpellet.The spittingratewas higher in single dry pelletmade fromplantproteinthanthosemadefromanimalprotein.To improvepalatabilityofPPandAPpelletswewashed theoriginalmaterialswith80%ethanol toremove theextractivecomponentandmadeeachsingledrypellet fromthosepre-treatedmaterials.Thespittingrateinsingledrypelletmadefrompre-

Rearingseason(days)Initial

Summer(90days) Autumn(91days)FM PP-SP PP-FS AP-SP FM PP-SP PP-FS AP-SP

Hepatosomaticindex(%)*1 1.1±0.0 1.4±0.1a 1.2±0.1a 1.2±0.2a 1.3±0.3a 1.4±0.2a 1.3±0.1a 1.2±0.0a 1.2±0.1a

Hematocritvalue(%) 53.6±3.4 61.5±7.4a 50.8±0.7a 57.0±4.9a 55.3±7.3a 46.2±2.1a 45.7±4.5a 50.6±6.5a 48.0±6.2a

Heamatochemicalcharacteristics Glucose(mg/dl)  144±25.2 237.8±51.8a 262.6±30.8a 267.0±41.3a 280.8±146.1a 138.6±10.5a 127.6±21.3a 143.0±12.1a 130.0±28.5a

 Totalprotein(g/dl) 4.0±0.5 4.3±0.7a 3.7±0.2a 4.3±1.5a 4.8±0.7a  4.1±0.5ab 3.7±0.2b  3.9±0.5ab 4.4±0.4a

 Totalcholesterol(mg/dl) 349.4±63.0 282.0±30.8a 203.4±21.7a 267.0±79.5a 276.4±101.0a 396.8±72.3a 245.6±29.0b 266.4±61.0b 346.0±82.1ab

 GPT(IU/l)*2 25.4±2.6 32.4±4.2a 59.2±44.1a 34.6±14.5a 44.4±19.9a 32.0±13.4a 30.8±14.8a 23.4±8.6a 33.8±11.4a

 ALP(IU/l)*3 148.6±33.8 156.4±34.3a 134.8±14.4a 181.0±64.0a 200.6±22.9a 143.4±43.4a 125.2±16.9a 126.5±23.7a 147.8±42.3a

Mean±standarddeviation(n=5).Valueshavingdifferentsuperscriptlettersaresignificantlydifferent(P<0.05).*1Theratioofliverweighttobodyweight.*2Glutamate-pyruvatetransaminase.*3Alkalinephosphates.ExperimentaldietsareshowninTable1.

45

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Noriko ISHIDA, Tomohiko KOSHIISHI, Tatsuo TSUZAKI, Koji MAENO, Satoshi KATAYAMA, Minoru SATOH, and Shuichi SATOH

treatedplantproteindecreased.Ontheotherhand,theoppositeresultwasshowninpre-treatedanimalproteinsthatthespittingrateincreased(Niinumaet al., 2012,Yamauchiet al., 2012). Fish meat analysis:Table5showstheresultsofthefishmeatanalysisofculturedfish.Intheproximatecompositionofall thedietgroups,moisturecontentdeclined and fat content increaseduntil the endof experiment. No difference was seen in thephosphorus content among thediet groups.TheEPA,DHAandn3HUFAcontentoffishfedAP-SPpelletswasalways lowerthan infish fedtheotherdiets, at times significantly less (p<0.05) in bothsummerandautumn.Theseresultsweresimilartotheanalysisofexperimentaldiets.

0

20

40

60

80

100

0 5 10 15 20

FM

PP-SP

AP-SP

(%)

(h)

Fig. 6.Evacuationofthedietfromthefishstomachafterasingleoraladministrationofdietat2%bodyweight.Valueareshownthepercentageofnitrogenin thestomachresidueperadministerednitrogen.ExperimentaldietsareshowninTable1.

Discussion

 Ithas longbeen thought that fishmealwas anecessary ingredient in fish feed.Generally, theformulated feeds foryellowtail containabout50%fishmeal. Recently, formulated feeds containinglower amounts of fish meal such as 30% havebeenproducedasacommercialproduct.Howevera fishmeal content of less than30%wouldhaveconsiderable financial benefits for aquacultureenablingcontinuedeconomicallyviableproduction.Therefore,wedevelopednon-fishmeal feedsandevaluatedthoseinafieldexperimentwithasimilaraquaculture environment.Weused oneyear oldyellowtailwhich is an intermediate size duringculturingandshowsrapidgrowthrequiringhighfeedcosts.Experimentalperiodsincludedthehigherfeedingactivity seasonof summerand the lowerfeedingactivityseasonofwinter.  In thepresent study (Tsuzaki et al., 2014), theplantproteinbaseddietsofPP-SPandPP-SPshowedasimilardaily feedingrateanddailyweightgain,better feedconversionratioandproteinefficiencyratio than the controlFM in summer season.Onthe otherhand, the animalproteinbaseddiet ofAP-SP showed a higher daily feeding rate andfeedconversionratio, lowerproteinefficiencyratiodemonstrating lowerproteinuptake thanothers.Wealsostudieduptakeofnutrientinthesenon-fishmealdietsandFMbyanalysisofyellowtailfeces.Itisclearthattheuptakeofprotein inthesenon-fishmealdietswerereducedby4- 9 %comparedtothecontrolFM. Then, in the autumn season, theplantproteinbased diets of PP-SP and PP-FS showed a lowperformancebecauseofthehigherdailyfeedingrateand feedconversionratio, lowerdailyweightgain.Theseresultsarethoughttobeduetothephysicalpropertiesof thediets.Becausetheseplantproteinbaseddietsdidnot sinkappropriatelyand flowedout fromthenetcagecomparedtotheotherdiets.Fromtheseresults,morestudiesareneededfortheimprovement of uptake for animal proteinbaseddietsandadjustmentofthephysicalcharacteristicsfor plant protein based diets. However, theseresultsdemonstrate thatnon-fishmealdietshavethepotentialtosupportthegrowthofoneyearold

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Non-Fish Meal Extruded-Pellet

yellowtailcompared to theresultsofTakagiet al. (2013).  For substitutematerials, plantproteinmaterialsuch as soy bean concentrate has been studied(Aoki et al., 2000a, 2000b).Wealsousedsoybeanconcentrate and confirmed its performance as asubstituteproteinforfishmealinthepresentstudy.In the field, it is sometimes believed that plantproteinmaterials stay longer in thestomach thanfishmeal.However, in our experiment, theplantproteinbaseddietsdidnotstay longeramongthedietgroups.Fishmealbaseddietwas the first tobeevacuated from the stomach. Inaddition, it issometimebelievedthatplantprotein fedyellowtailismore susceptible to epidemicdisease than fishmealbaseddiet.However, inourexperiment,thosephenomenawerenotseen (Ishidaet al., 2013).Wealsocomparedthestomachevacuationrateandthe

in vitrodigestionusingonlyoneproteinmaterialdiet, and foundminimaldifference (Tohata et al., 2012).Morestudiesareneeded in futureusing lowcostmaterialssuchasdefattedsoybeanmeal,cornglutenmealandcanolaoil. As forsubstituteanimalproteinmaterials, therearemeatmeal,chickenmeal,feathermeal,andporkmeal.Feathermealandmeatmealwerereportedtobeusefulforyellowtail(Shimenoet al., 1993a, 1993b, 2000). However, the animal protein studies arefewerthanplantproteinstudies.There ispotentialtousechickenmealandporkmeal.As therearefewstudiesaboutporkmeal,wetried touseporkmealinthepresentstudy.PorkmealhaslessDHA,DPAandn3HUFAoffattyacidthanFM.Asimilartendencywasseen in thewholefishbodyandthemeat of yellowtail fed byporkmeal baseddiet.However,thereisnosignificanteffectongrowthand

Initial FM PP-SP PP-FS AP-SP FM PP-SP PP-FS AP-SPProximate composition (%)

Moisture 71.9 ± 0.8 64.7 ± 1.7 64.5 ± 1.4 64.8 ± 1.7 65.6 ± 4.1 60.6 ± 4.6 60.0 ± 3.0 60.3 ± 1.3 62.5 ± 0.9Crude ash 2.3 ± 0.5 1.3 ± 0.3 1.3 ± 0.0 1.4 ± 0.1 1.4 ± 0.1 1.4 ± 0.1 1.3 ± 0.1 1.4 ± 0.2 1.4 ± 0.1Crude protein 22.1 ± 0.2 21.4 ± 0.6 20.3 ± 1.1 20.5 ± 0.8 20.7 ± 1.3 20.1 ± 2.3 20.5 ± 1.6 22.0 ± 1.0 22.0 ± 0.5Crude lipid 3.7 ± 0.9 11.5 ± 2.1 12.8 ± 2.6 10.6 ± 1.2 10.1 ± 3.3 16.0 ± 6.2 17.9 ± 4.7 16.0 ± 1.2 14.3 ± 1.5

P (mg/g) 15.5 ± 4.4 4.2 ± 1.7 5.5 ± 2.8 5.0 ± 1.5 4.3 ± 2.5 4.6 ± 1.1 4.5 ± 1.6 4.4 ± 0.7 4.7 ± 1.4

Fatty acid composition (%)14: 0 4.2 ± 0.4 4.0 ± 0.3 3.1 ± 0.6 3.4 ± 0.7 3.9 ± 0.2 4.3 ± 0.2 3.9 ± 0.4 3.8 ± 0.3 4.2 ± 0.216: 0 19.6 ± 0.9 18.0 ±0.8 16.2 ± 1.3 16.8 ± 1.1 16.1 ± 0.3 16.4 ± 0.4 16.5 ± 0.7 15.6 ± 0.6 16.0 ± 0.518: 0 5.6 ± 0.5 4.2 ± 0.3 4.0 ± 0.1 4.2 ± 0.5 4.5 ± 0.4 3.4 ± 0.1 3.4 ± 0.1 3.3 ± 0.1 3.9 ± 0.0

16: 1n-7 5.9 ± 0.8 6.6 ± 0.3 5.8 ± 0.5 5.9 ± 0.4 5.9 ± 0.3 7.0 ± 0.3 6.3 ± 0.2 6.2 ± 0.2 6.6 ± 0.318: 1n-9 21.4 ± 1.4 23.2 ± 2.2 25.0 ± 0.8 25.6 ± 1.3 25.0 ± 1.9 20.5 ± 1.9 23.5 ± 1.6 22.6 ± 2.0 22.1 ± 0.320: 1n-9 3.1 ± 0.8 5.1 ± 0.3 5.4 ± 0.3 5.7 ± 0.5 9.4 ± 1.4 5.6 ± 1.2 5.3 ± 0.1 5.6 ± 0.3 6.5 ± 0.220: 1n-11 0.6 ± 0.9 0.2 ± 0.0 0.2 ± 0.0 0.2 ± 0.0 0.3 ± 0.0 0.6 ± 0.9 0.2 ± 0.0 0.2 ± 0.0 2.9 ± 0.122: 1n-11 2.7 ± 0.3 3.4 ± 0.4 3.7 ± 0.5 4.0 ± 0.6 8.7 ± 0.7 3.6 ± 0.6 3.1 ± 0.1 3.7 ± 0.4 6.3 ± 0.4

18: 2n-6 5.6 ± 0.2 5.8 ± 0.2 8.6 ± 0.3 8.6 ± 0.1 7.2 ± 0.2 5.3 ± 0.1 8.4 ± 0.1 8.4 ± 0.1 7.4 ± 0.220: 4n-6 1.2 ± 0.2 0.9 ± 0.0 0.9 ± 0.1 0.8 ± 0.1 0.5 ± 0.1 0.8 ± 0.0 0.8 ± 0.1 0.8 ± 0.0 0.4 ± 0.0

18: 3n-3 0.6 ± 0.1 1.1 ± 0.0 1.3 ± 0.1 1.2 ± 0.1 0.9 ± 0.1 1.0 ± 0.0 1.2 ± 0.0 1.2 ± 0.0 0.8 ± 0.018: 4n-3 0.9 ± 0.1 1.6 ± 0.1 1.3 ± 0.0 1.3 ± 0.1 1.6 ± 0.3 1.5 ± 0.1 1.3 ± 0.1 1.4 ± 0.1 1.5 ± 0.020: 4n-3 0.5 ± 0.0 0.9 ± 0.0 0.7 ± 0.0 0.7 ± 0.0 0.6 ± 0.1 0.7 ± 0.0 0.6 ± 0.0 0.7 ± 0.0 0.6 ± 0.020: 5n-3 (EPA) 5.3 ± 0.2 6.2 ± 0.5a 5.3 ± 0.4ab 4.8 ± 0.9ab 4.6 ± 1.1b 6.6 ± 0.2a 5.0 ± 0.3bc 5.1 ± 0.3b 4.7 ± 0.1c

22: 5n-3 (DPA) 2.2 ± 0.2 2.4 ± 0.1a 2.2 ± 0.2ab 2.1 ± 0.2b 1.5 ± 0.1c 2.4 ± 0.2a 2.0 ± 0.1b 2.1 ± 0.1b 1.4 ± 0.1c

22: 6n-3 (DHA) 11.4 ± 1.6 10.9a 11.3 ± 1.0a 9.4 ± 3.1a 4.9 ± 1.2b 11.4 ± 0.6a 10.2 ± 0.8a 10.5 ± 1.2a 5.1 ± 0.5b

Others 9.2 ± 2.8 5.9 ± 1.5 5.0 ± 0.3 5.2 ± 1.0 4.5 ± 2.4 8.9 ± 1.9 7.9 ± 2.0 8.5 ± 2.0 9.8 ± 0.2n-3 HUFA 20.3 ± 1.4 21.7 ±2.5a 20.9 ± 1.6a 18.3 ± 4.3ab 13.2 ± 2.9b 22.7 ± 0.6a 19.2 ± 1.2b 19.8 ± 1.5b 13.2 ± 0.6c

Mean ± standard deviation (n =5).Values having different superscript letters are significantly different (P <0.05).Experimental diets are shown in Table 1.Fatty acid compositions are shown in Table 2.

Table 5. Proximate composition, phosphorus content, and fatty acid composition of muscle of yellowtail (n=5) fed theexperimental diets

Rearing season (days) Summer (90 days) Autumn (91 days)

Phosphorus content

Table 5.Proximatecomposition,phoshorusconntent,andfattyacidcompositionofmuscleinyellowtail(n=5)fedtheexperimentaldiets

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Noriko ISHIDA, Tomohiko KOSHIISHI, Tatsuo TSUZAKI, Koji MAENO, Satoshi KATAYAMA, Minoru SATOH, and Shuichi SATOH

survival.Onlyslightlylessproteindigestioninporkmealbaseddietwas seen than theplantproteinbaseddiet.Andfeedingactivityonporkmealbaseddietswasactive.Fromtheseresults,porkmealwasthoughttobeavailableasasubstitutematerial. Thebiggestproblemhasbeenshowntobe thereductionof feedingactivitywhenfishare fed lowfishmeal contentdiets (Aoki et al., 2000a, 2000b, 2000c). However, it is reported that an addedpalatability ingredients improved the feedingactivityineel(Takiiet al., 1984),yellowtail(Takiiet al., 1994),andtigerpuffer(Takiiet al., 1998).Inthepresentstudy,wefoundthatfishdidnotespeciallypreferplantproteintoanimalproteinandfishmeal.However, afterwashing the feed ingredients toremovetheextractivecomponent,thespittingratiodecreased inplant ingredient feedsand increasedinanimalprotein feeds,whichsuggested that theextractivecomponentsmightaffect feedingactivity(Niinumaet al., 2012,Yamauchiet al., 2012).Then,weaddedsomepalatabilityingredientstotheplantbaseddiet,fishswallowingratiowas increasedandspittingratiowasdecreased.Fromtheseresults,weused theskipjackpeptide (SP)and fishsauce (FS)aspalatability ingredients inorder to improve thefeedingactivity. In theresults,higherpalatabilitywasseenwhenusingbothingredients.Thebiggestproblemofreductionof feedingactivity innon-fishmealdietswasthoughttobealmostresolvedbytheadditionofpalatabilityingredients. Themeatqualityofyellowtail fedwithnon-fishmealdietswerecomparedtocontrolyellowtailbyapaneltest,whichshowedadifferenceincolorandsmell.Thenweused colorimeter andElectronicNoseSystemofAlphaMOS(http://www.alpha-mos.co.jp/products/sensory.html).The fish fedbynon-fishmealdietshadwhitermuscleanda less fishysmell (Tohataet al., 2013).Now, theeffectofnon-fishmealdietsonfishmeatqualityandasamethodof enhancing themeat quality control is beingdetermined.  Asdescribedabove,wealternated fishmeal toplantoranimalproteinmaterials tomakenon-fishmealdiets,andfedthemtooneyearoldyellowtail,andgotsimilargrowth,bodyandbloodcompositions.Themainreason for thesimilargrowthrateswasthoughttobetheadditionofpalatabilityingredients

and enzyme mixtures (Table 1) . As we usedbothplant and animalmaterials,we suggest thepossibilityofmanymaterialsfornon-fishmealdiets.Morestudyisneededtoimprovelowcostdietsandproducehigherqualitymeat. This work was supported by Research andDevelopmentProjects forapplication inpromotingnewpolicyofagriculture,forestryandfisheriesfromtheMinistryofAgriculture,ForestryandFisheriesofJapan.

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