THE USE OF SOY PRODUCTS AND OTHER PLANT PROTEIN SUPPLEMENTS IN AQUACULTURE FEEDS

THE USE OF SOY PRODUCTS AND OTHER PLANT PROTEIN SUPPLEMENTS IN AQUACULTURE FEEDS by DEAN M. AKIYAMA Americn Soyben Assocition 541 Orchrd Rod, # 11-03 Lit Towers Singpore

Aquculture feed production worldwide is expnding rpidly. In Asi lone, this feed sector hs incresed from 980,000 MT to 2,500,000 MT from 1986 to 1989. This reltively new, immture, nd highly profitble mrket is the fstest growing of ll niml feed mrkets. Trditionlly, niml protein supplements were the foundtion of ny quculture feed formultion. However, given the limited world supplies nd the incresing price of these niml protein supplements qutic nutritionists re considering lterntive protein sources. This trend will be further emphsized s these quculture feed mrkets mture, thereby incresing competition nd decresing profit mrgins. Plnt protein supplements re generlly cheper per unit of nutrient s compred to the niml protein supplements. The incresed use of plnt protein supplements in quculture feeds will be dependent on relible nutrition reserch. There re limittions in our knowledge of nutrition of qutic species. The comprison of vrious nutritionl studies re complicted by differences in reserch methodology such s size nd physiologicl stte of the niml, diet composition nd processing environmentl conditions, nd experimentl fcilities. The relibility of dt is lso dependent on growth rte, survivl rte, nd feed conversion rtios. Current quculture feed formultions re bsed on intuition nd unknown growth fctors, rther thn nutritionl science. Animls do not require feed ingredients or formuls, but rther the nutrients which re prt of the chemicl composition of these ingredients nd feed formuls. Therefore, feed formul is meningless if we don t understnd the nutritionl principles involved in formulting the feed. In generl, plnt protein supplements re lower in some essentil mino cids, energy, nd minerls such s phosphorous s compred to niml protein supplements. These prmeters need to be considered in feed formultions bsed on plnt proteins. The purpose of this pper is to discuss the nutritionl vlue of plnt protein supplements. 2

AVAILABILITY OF NUTRIENTS The vilbility of nutrients from feed ingredient is essentil in determining the nutritionl vlue of the feed ingredient. A nutrient my be present, however, if it is unvilble to the niml, its presence is nutritionlly meningless. A mjor limittion in quculture nutrition is the lck of nutritionl vilbility dt for feed ingredients for the different qutic species. Protein nd essentil mino cids: Protein nd essentil mino cid digestibility by mrine shrimp nd chnnel ctfish for common feed ingredients re presented in Tble 1 (Akiym et l., 1988; Robinson nd Wilson, 1985). Protein digestibility of these ingredients rnge from 74.6% to 89.9% nd 74.0% to 87.0% for shrimp nd ctfish, respectively. In shrimp, soyben mel hd higher protein digestibility vlue s compred to fish mel, squid mel, nd shrimp mel. The protein digestibility ws higher by 10%, 11%, nd 17% s compred to fish mel, squid mel, nd shrimp mel, respectively. A misconception of mny nutritionists is tht niml proteins re more digestible thn plnt proteins. Protein digestibility does not lwys reflect essentil mino cid digestibility. In mrine shrimp, shrimp mel hd protein digestibility of 74.6% (Tble 1). However, ll of the essentil mino cids hd higher digestibility vlues which rnged from 75.4% to 85.7%. Lysine, rginine, nd threonine hd digestibility vlues of 85.7%, 81.8%, nd 83.7%, respectively. The lower protein digestibility ws relted to the nlyticl methods for determining protein digestibility nd its reltionship to chitin which is reltively undigestible. In chnnel ctfish, this contention is most evident in soyben mel nd penut mel. Soyben mel hd protein digestibility of 77.0% with essentil mino cid digestibilities rnging from 78.7% to 96.7%. Lysine, rginine, threonine, nd methionine hd digestibility vlues of 94.0%, 96.7%, 81.9%, nd 84.6%, respectively. Penut mel hd protein digestibility of 74.0% with essentil mino cid digestibilities rnging from 89.5% to 97.8%. Lysine, rginine, threonine, nd methionine hd digestibility vlues of 94.4%, 97.8%, 93.1%, nd 90.5%, respectively. Therefore, in feed formultions, vilble mino cid vlues should be utilized rther thn totl or digestible protein. 3

In ctfish, lysine, rginine, nd methionine vilbility were higher in soyben mel nd penut mel s compred to fish mel (Tble 1). In shrimp, ll of the essentil mino cids mesured were higher in vilbility in soyben mel s compred to fish mel, squid mel, nd shrimp mel. Plnt protein utiliztion in quculture feeds would be enhnced if feeds were formulted on vilble rther thn totl mino cid vlues. Energy: Plnt protein supplements re considerbly lower in energy s compred to fish mel (Tble 2). The blnce of protein nd energy is essentil in the formultion of efficient feeds. As plnt protein supplements replce niml protein supplements in feed formultion, energy vlues need to be monitored. A plnt protein supplement high in vilble energy is fullft soyben mel (FFSBM). FFSBM hs metbolizble energy vlue of 96% thn tht of fish mel in rinbow trout (Tble 2). The oil content of FFSBM is reltively stble due to the high levels of nturlly occurring tocopherols (Holmes, 1988). Rw soybens contin severl ntinutritionl fctors which ffect niml growth nd performnce (Rckis, 1972; Liener, 1975). However, it is well documented tht the het tretment of rw soybens improves its utiliztion. Smith (1988) reported tht for mximum metbolizble energy in rinbow trout, soybens should be processed t minimum of l75 C. Phosphorous : A common oversight of quculture feeds formulted with high levels of plnt protein supplements is vilble phosphorous content. It is generlly believed tht phosphorous vilbility is considerbly less in plnt versus niml products nd differs significntly by species. Phytic cid found in plnt products binds phosphorous s well s other minerls lowering their vilbility (Ntionl Reserch Council, 1983). Phytte bound phosphorous hs vilbility vlues in chnnel ctfish, red sebrem, rinbow trout, nd common crp of 0%, 0%, 0-19%, nd 8-38%, respectively (Andrews et l., 1973; Ogino et l., 1979; Skmoto nd Yone, 1979). However, phosphorous vilbility, considering ll forms of phosphorous in soyben mel for chnnel ctfish nd mrine shrimp re 50% nd 40%, respectively (Tble 3). Phosphorous vilbility vlues for other plnt protein supplements re unvilble. 4

In quculture. feed formultions, cost per unit of vilble phosphorous should be considered. For exmple, totl phosphorous in Kg of mono-bsic nd dibsic forms of clcium phosphte re similr t 210 gm nd 190 gin, respectively. Given the vilbility vlues for common crp of 94% nd 46%, vilble phosphorous in the mono-bsic nd dibsic forms would be 197 gin nd 87 gin, respectively. Di-clcium phosphte is cheper per Kg thn mono-clcium phosphte, however, the vilble phosphorous content is only 44% of the ltter. In feed formultions contining high levels of plnt protein supplements, vilble phosphorous needs to be considered nd phosphorous supplements re usully dded. FEED FORMULATIONS AND CHEMICAL COMPOSITIONS WITH COMMERCIAL APPLICABILITY Good qulity feeds re dependent on the chemicl composition (nutrients), ingredient qulity, nd processing technology. The chemicl composition of feeds is in turn dependent on the formultion. All of these fctors re essentil nd interdependent. Little is known bout ingredient qulity stndrds while most published informtion is on chemicl composition or nutrition. This lck of informtion is reflected in the feed industry where ingredient qulity is the mjor limittion on the consistent production of good qulity feeds. Feed Processing limittions restrict efficient feed production nd formultion flexibilities. Approximte nutritionl requirements of qutic species re redily vilble however, the nutritionl composition of commercil feeds usully exceed the nimls requirements. If greter emphsis ws plced on nutritionl principles rther thn formultions, feeds would cost less without scrificing niml performnce. Chnnel ctfish: Chnnel ctfish feed formultions re firly consistent in the U.S. Model chnnel ctfish feed formultions nd chemicl compositions re presented in Tbles 4-5 (Robinette, 1984). Plnt proteins comprise 82.4%, 84.9%, nd 76.6%, of the totl protein of the strter feed nd both grower feeds, respectively. These plnt proteins were supplemented primrily from soyben 5

mel nd penut mel with niml protein being supplemented by fish mel nd met & bone mel. Feed cost, production levels, nd feed conversion rtios of commercil chnnel ctfish frms re pproximtely US$350.00/MT, 5 MT/h, nd 1.6, respectively. Therefore, feed cost per kg of chnnel ctfish produced is US$0.56. Common crp: Two common crp feed formultions nd chemicl compositions re presented in Tbles 6-7 (Akiym, unpublished dt). Plnt proteins comprised 78.3% nd 56.4% of the totl protein of feeds A nd B, respectively. These plnt proteins were supplemented primrily from soyben mel with niml proteins being supplemented by fish mel. These feeds were fed to common crp in floting cges t stocking densities of 5 kg/rn 3 nd 10 kg/rn 3. After 59 dys, there were no differences in growth rtes, survivl rtes, nd feed conversion rtios between the plnt protein nd niml protein bsed feeds (Tble 8). These mesured prmeters were well within cceptble stndrds. Rinbow trout: Two rinbow trout feed formultions nd chemicl compositions re presented in Tbles 9-10 (Smith et l., 1988). Plnt proteins comprised 74.8% nd 33.1% of the totl protein of feeds A nd B, respectively. These plnt proteins were supplemented primrily from full-ft soyben mel, cottonseed mel, nd corn gluten mel with niml proteins being supplemented by fish mel nd blood flour. These feeds were fed to 10 different strins of rinbow trout. In experiment I, the high plnt protein feed took longer to rech finl weight nd hd higher feed conversion rtio s compred to the niml protein feed (Tble 11). In experiment II, there were no differences between feeds for these prmeters. 6

The primry considertion of ny frmer is profitbility. A simple economic comprison of these feeds is presented (Tble 12). In experiment I, though feed conversion rtio of the plnt protein feed ws higher, the feed cost per kg of fish produced ws lower by 8.5%. In experiment ii with similr feed conversion rtios, the feed cost benefit ws improved by 16.7%. Therefore, the cost effectiveness of the plnt protein feed ws better thn the niml protein feed for the production of rinbow trout. Mrine shrimp: Two mrine shrimp feed formultions nd chemicl compositions re presented in Tbles 13-14 (Akiym nd FSGP Aquculture Reserch, 1990). Plnt proteins comprised 72.2% nd 50.3% of the totl protein of the feeds, A nd B, respectively. These plnt proteins were supplemented primrily from soyben mel nd whet products with niml proteins being supplemented by fish mel, squid mel, nd shrimp mel. These feeds were fed to Peneus monodon in outdoor concrete tnks t stocking density of 30/m 2 (Tble 15). After 42 dys, there were no differences in growth rtes, survivl rtes, nd feed conversion rtios between the plnt protein nd niml protein bsed feeds. These mesured prmeters were well within cceptble stndrds. SUMMARY The commerciliztion of quculture is growing, thereby incresing the demnd for quculture feeds. Trditionlly, these feeds hve been bsed on niml protein. However, due to cost nd vilbility considertions, it is inevitble tht more plnt protein supplements will be utilized in the feeds. Plnt protein supplements re more cost effective source of nutrients s compred to niml protein supplements. The incresed cceptbility nd utiliztion by the feed industry will be dependent on relible nutrition reserch. All plnt protein supplements re being used to some extent in quculture feeds. Of ll plnt protein supplements, soyben mel hs been the most extensively evluted nd most commonly used in commercil quculture feeds. 7

REFERENCES Akiym, D.M.7S.R. Coelho, A.L. Lwrence, nd E.H. Robinson. 1988. Apprent digestibility of feedstuffs by the mrine shrimp Peneus vnnmei Boone. Bull. Jpn. Soc. Sci. Fish. 55(1) :91. Akiym, D.M. nd FSGP Aquculture Reserch. 1990. The use of soyben mel to replce white fish mel in commercilly processed Peneus monodon Fbricus feeds in Tiwn, R.O.C. In: M. Tked nd T. Wtnbe (Editors), The Current Sttus of Fish Nutrition in Aquculture: The Proceedings of the Third Interntionl Symposium on Feeding nd Nutrition in Fish, August 28-September 1, 1989, Tob, Jpn. Andrews, J.W., T. Muri, nd C. Cmpbell. 1973. Effects of dietry clcium nd phosphorus on growth, food conversion, bone sh nd hemtocrit levels of ctfish. J. Nutr. 103:766. Holmes, B. 1988. Qulity control of rw mteril nd finished product in full-ft soy production. ASA Technicl Bulletin, Vol. 2, AQ 9. Liener, I.E. 1975. Effects of nti-nutritionl nd toxic fctors on the qulity nd utiliztion of legume proteins. In: M. Friedmn (Editor) Protein Nutritionl Qulity of Foods nd Feeds. Mrcel Deckker, New York. Ntionl Reserch Council, 1983. Nutrient requirements of wrmwter fishes nd shellfishes. Ntionl Acdemy Press, Wshington, DC. Ogino, C, L. Tkeuchi, H. Tked, nd T. Wtnbe. 1979. Avilbility of dietry phosphorus in crp nd rinbow trout. Bull. Jpn. Soc. Sci. Fish. 45:1527. Rckis, J.J. 1972. Biologiclly ctive components. In: A.K. Smith nd S.J. Circle (Editors), Soybens: Chemicl nd Technology. AVI Publishing Co., Westport, Connecticut. Robinette, H.R. 1984. Feed formultion nd processing. In: E.H. Robinson nd R.T. Lovell (Editors), Nutrition nd Feeding of Chnnel Ctfish (Revised). Southern Coopertive Series Bull. 296, Texs A&M University, College Sttion, Texs. Robinson, E.H. nd R.P. Wilson. 1985. Nutrition nd feeding. In: C.S. Tucker (Editor), Chnnel Ctfish Culture. Elsevier Science Publishers B.V., Amsterdm. Skmoto, S., nd Y. Yone. 1979b. Avilbilities of phosphorus compounds s dietry phosphorus sources for red se brem. J. Fc. Agric. Kyushu Univ. 23:177. Smith, R.R. 1988. Soyben nd whet flour by-products in trout feeds. Americn Soyben Assocition Technicl Bulletin. Americn Soyben Assocition, Singpore. Smith, R.R., H.L. Kincid, J.M. Regenstein nd G.L. Rumsey. 1988. Growth, crcss composition, nd tste of rinbow trout of different strins fed diets contining primrily plnt or niml protein. Aquculture (70):309. 8

Tble 1. Protein nd mino cid digestibility vlues for vrious feed ingredients Protein ARG LYS LEU ILE THR VAL HIS PHE MET Mrine shrimp b Soyben mel 89.9 91.4 91.5 88.4 90.2 89.3 87.9 86.3 89.6 -- Fish mel 80.7 81.0 83.1 80.7 80.4 80.6 79.4 79.0 71.1 -- Squid mel 79.7 79.4 78.6 79.4 77.2 79.7 79.3 73.6 74.1 -- Shrimp mel 74.6 81.8 85.7 82.1 81.6 83.7 79.0 75.4 75.6 -- Chnnel ctfish c Fish mel 87.0 90.9 86.4 89.1 87.2 87.6 87.0 84.8 87.4 82.9 Cottonseed mel 81.0 90.5 71.0 76.4 71.7 76.8.76.1 82.0 83.5 76.3 Soyben mel 77.0 96.7 94.0 83.5 79.8 81.9 78.7 87.9 84.4 84.6 Penut mel 74.0 97.8 94.4 95.2 93.2 93.1 93.1 89.5 96.1.90.5 Vlues in percent digestibility of totl content. b Akiym et l., 1988. c Robinson nd Wilson, 1985. Tble 2. Energy vlues for vrious feed ingredients Rinbow trout Chnnel ctfish Tilpi Ingredient (ME, Kcl/g) (DE, Kcl/g) (DE, Kcl/g) Fishmel b 3.80 3.90 4.04 Cottonseed mel 2.08 2.55 - Rpeseed mel 2.47 - - Soyben mel solvent extrcted - 2.58 3.34 dehulled solvent extrcted 2.89 - - full-ft 3.64 - - b Ntionl Reserch Council, 1983. Vries with type of fish mel. 9

Tble 3. Phosphorous vilbility vlues for vrious sources nd ingredients Rinbow Chnnel Common Mrine trout b ctfish b crp b shrimp c Sodium phosphte, mono 98 90 94 - Potssium phosphte, mono Clcium phosphte 98-94 - mono-bsic 94 94 94 - dibsic tribsic 71 64 65-46 13 - - Fish mel 74 40 24 47 Yest 91-93 - Soyben mel - 50-40 Shrimp mel - - - 30 Squid mel - - - 77 Vlues in percent vilbility. b Ntionl Reserch Council, 1983. c Akiym (unpublished dt). Tble 4. Ingredient composition of chnnel ctfish feeds Ingredient Strter Grower A Grower B Fish mel 10 8 - Soyben mel (48%) 37 48.25 - Soyben mel (44%) - - 47.5 Met nd bone mel - - 15 Penut mel 18 - - Distillers dry solubles 7.5 - - Corn Rice brn 23.5-29.1 10 33 - Whet middlings - - 1.75 Di-C-P 1.5 1 0.25 Whey - - 2.4 Pellet binder b 2.5 2 - Ft - 1.5 - Vitmin/Minerls 0.18 0.14 0.14 Robinette, 1984. Percent s fed bsis. b Not required if feeds re extruded. 10

Tble 5. Estimted chemicl composition of chnnel ctfish feeds Nutrient Strter Grower A Grower B Protein 35.4 32.0 31.1 plnt protein (% of totl) 82.4 84.9 76.6 niml protein (% of totl) 17.6 16.1 23.4 Ft 4.8 5.0 4.3 Fiber 5.3 3.3 4.0 Ash 6.6 6.5 8.2 Clcium 1.0 0.6 1.5 Phosphorous (vilble) 0.5 0.4 0.5 percent s fed bsis. Tble 6. Ingredient composition of common crp feeds Ingredient A B Fish mel 10.8 21.6 Soyben mel 45.0 25.0 Whet pollrds 12.6 24.4 Rice brn 20.0 20.0 Di-C-P 4.6 3.3 Fish oil 1.8 0.7 Methionine 0.2 0.1 Limestone 2.4 2.3 Vitmin/Minerl premix 2.6 2.6 percent s fed bsis. Tble 7. Estimted chemicl composition of common crp feeds Nutrient A B Protein 30.1 29.9 plnt protein (% of totl) 78.3 56.4 niml protein (% of totl) 21.7 43.5 Ft 6.5 6.4 Fiber 6.4 6.2 Ash 12.5 12.4 Clcium 2.8 3.0 Phosphorous (vilble) 0.7 0.7 As fed bsis. 11

Tble 8. Results of the common crp feeding tril conducted in floting cges Experiment I Experiment II A B A B Initil weight (gm) 57 57 73 73 Stocking density (kg/m 3 ) 5.0 5.0 10.0 10.0 Experimentl time (dys) 59 59 59 59 Finl weight (gin) 163.5 b 175.8 b 232.7 b 249.4 b Weight gin (%) 186 207 220 242 Survivl rte (%) 94.8 b 94.6 b 99.4 b 99.3 b Finl density (kg/m 3 ) 13.5 14.2 31.8 33.9 Feed conversion rtio 2.3 b 2.2 b 1.9 b 1.8 b Vlues re mens for 3 replictes. b Mens within n experiment nd in the sme row with different superscripts differ (P<0.05). Tble 9. Ingredient composition of rinbow trout feeds Ingredient A B Fish mel, nchovy 7.5 30.0 Soyben mel, full-ft 40.0 7.5 Cottonseed mel Corn gluten mel 15.0 7.0 10.0 7.5 Blood flour 5.0 5.0 Yest, brewers dry 5.0 5.0 Whet middlings - 20.0 Whey, dried 6.0 - Fish oil 3.0 3.0 Soyben oil Molsses (sugr beet) - 6.0 30% moisture 10.0 3.0 Vitmin/Minerl premix 5.0 5.0 Smith et l., 1988; Percent s fed bsis. 12

Tble 10. Estimted chemicl composition of rinbow trout feeds Nutrient A B Protein 42.4 45.0 plnt protein (% of totl) niml protein (% of totl) 74.8 25.2 33.1 66.9 Ft 11.0 13.0 Fiber 2.1 0.7 Ash 9.2 9.7 Energy (ME, Kcl/kg) 3529 3430 Clcium b 0.4 1.0 Phosphorous (vilble) b 0.4 0.8 As fed bsis. b Not including premix. Tble 11. Dys required for rinbow trout to increse in verge weight from 2 to 200 g nd feed conversion rtios Dys to finl weight FCR Experiment A B A B I 207 b 203 c 159 b 1.49 c II 187 b 185 b 113 b 113 b Smith et l., 1988; Vlues re mens for 4 replictes by 5 rinbow trout strins. b, c Mens in sme row with different superscript differ (P<0.05). 13

Tble 12. Cost dvntges of high plnt protein rinbow trout feeds Feed cost (US$/Kg) FCR Feed cost (US$/Kg) per Kg fish produced Experiment I Diet A 1.59 0.37 0.59 Diet B 1.49 0.43 0.64 Experiment II Diet A 1.13 0.37 0.42 Diet B 1.13 0.43 0.49 Smith et l., 1988. Tble 13. Ingredient composition of mrine shrimp feeds Ingredient A B Soyben mel 40.0 20.0 White fish mel 6.0 18.0 Whet brn 4.1 12.5 Limes tone 0.7 - Di-C-P 3.0 1.0 Fish oil 0.7 - Whet flour 14.6 16.8 Potssium bicrbonte 0.4 1.2 Soy lecithin 0.5 0.5 Whet gluten 5.0 5.0 Shrimp mel 7.0 7.0 Squid mel 7.0 7.0 Vitmin/Minerl premix 3.0 3.0 Yest 2.0 2.0 Sodium phosphte 2.0 2.0 Zeolite 2.0 2.0 Dehydrted fish solubles 1.0 1.0 Squid oil 1.0 1.0 Akiym 1990; Percent s fed bsis. 14

Tble 14. Estimted chemicl composition of mrine shrimp feeds Nutrient A B Protein 37.8 38.0 plnt protein (% of totl) 72.2 50.3 niml protein (% of totl) 27.8 49.7 Ft 5.3 5.3 Fiber 3.2 3.6 Ash 17.9 18.2 Clcium 2.4 2.6 Phosphorous (totl) 2.0 2.0 Percent s fed bsis. Tble 15. Results of the Peneus monodon feeding tril conducted in outdoor concrete tnks Diets A B Initil weight (g) 3.6 3.8 Stocking density (#/m 2 ) 30.0 30.0 Experimentl time (dys) Finl weight (g) 42 12.8 42 12.3 Weight gin (%) 256 b 224 b Survivl rte (%) 91.3 b 92.8 b Finl biomss (g/m 2 ) 351.1 343.5 Feed conversion rtio 1.3b 1.2 b Akiym, 1990. Vlues re mens for 4 replictes. b Mens in the sme row with different superscripts differ (P<0.05). 15