A study was conducted to evaluate the effects of meat and bone meal （MBM） and poultry by-product meal （PBM） as the replacement of fishmeal in the diets on the growth performance, survival and apparent digestibilit...A study was conducted to evaluate the effects of meat and bone meal （MBM） and poultry by-product meal （PBM） as the replacement of fishmeal in the diets on the growth performance, survival and apparent digestibility coefficient （ADC） of Japanese flounder （Paralichthys olivaceus）. The experimental diets included 0%, 20%, 40%, 60% and 80% MBM or PBM replacement of total fishmeal respectively. All diets were iso-nitrogenous and isocaloric. The results showed that there are no significant differences （P 〉0.05） in growth performance among the treatments fed with 0% -60% MBM replacement of fishmeal, while the percent weight gain （WG, % ）, body length gain （BLG, % ） and ADC significantly decrease when fishmeal is replaced by 80% MBM. The result showed also that there are no significant differences （P 〉0.05） in growth performance and ADC among all treatments fed with the diets with 0% -80% replacements of fishmeal with PBM.展开更多
Background:Recent investigations highlighted that Hermetia illucens(BSF)larva meal can be a valuable alternative protein source for aquafeed production.In this study,in substitution of fishmeal,we used increasing incl...Background:Recent investigations highlighted that Hermetia illucens(BSF)larva meal can be a valuable alternative protein source for aquafeed production.In this study,in substitution of fishmeal,we used increasing inclusion levels of a partially defatted BSF larva meal in low fishmeal-based diets for rainbow trout(Oncorhynchus mykiss Walbaum)and we evaluated the related implications in terms of growth performance,physical characteristics,proximate and fatty acid(FA)compositions of the fillets,gut and liver histology,and diet digestibility.In a 131-day trial,576 fish(100.1±9.29 g)were randomly allotted to 24 tanks(24 fish/tank,4 replicates/treatment).Six experimental diets were produced to have partial replacement of fishmeal(0,10%,20%,30%,40%and 50%)by increasing levels of BSF meal(0%[BSF0],3%[BSF3],6%[BSF6],9%[BSF9],12%[BSF12]and 15%[BSF15]on as fed basis,respectively).Results:No differences were observed among the treatments for all the considered growth performance parameters.The viscero and hepato-somatic indexes showed significant differences among the treatments,with the highest values observed in the BSF15 group.No differences were recorded in terms of fillet’s physical characteristics,dry matter(DM),crude protein(CP)and ether extract(EE)contents.Total saturated and monounsaturated FA increased,while polyunsaturated FA(particularly n-3 FA)decreased while increasing the HI meal inclusion in the diet.Histopathology of liver and gut was not affected,whereas,in posterior gut,villi were higher in BSF6 and BSF9 compared to BSF3 fish.The apparent digestibility of DM,CP,EE and gross energy did not vary among the treatments.Conclusions:These results suggest that a partially defatted BSF meal could be included up to 15%in low fishmeal-based diets for rainbow trout with no adverse effects on growth performance,fillet’s physical characteristics,gut and liver health,and diet digestibility.On the contrary,the fillet FA composition worsened while increasing the level of BSF meal in the diet.展开更多
The present study was carried out to investigate the total and partial replacement of Jojoba meal （JM）, Simmondsia chinensis, with fishmeal （FM） at different levels （0%, 25%, 50%, 75%, and 100%） on growth perfor...The present study was carried out to investigate the total and partial replacement of Jojoba meal （JM）, Simmondsia chinensis, with fishmeal （FM） at different levels （0%, 25%, 50%, 75%, and 100%） on growth performance, feed utilization, and carcass composition of Nile tilapia, Oreochromis niloticus fingerlings. Fingerlings with an average weight of 1.65 ± 0.01 g/fish stocked at a rate of 10 fish/aquarium for 84 days experimental period. All experimental diets were isocaloric （437.69 kcal/100 g Dry Matter, DM） and isonitrogenous （30.5% crude protein） and supplemented with 0.5% L-Methionine and 0.5% L-Lysine Hcl. Results showed that there were a significant differences （P 〈 0.05） in final body weights, average daily gain （g fish^-1 dayl）, specific growth rate （SGR, % day^-1）, feed conversion ratio （FCR）, protein efficiency ratio （PER）, protein productive value （PPV%） and energy retention （ER%） among the tested groups. Nile tilapia fingerlings fed on the diet containing 25% S. chinensis protein exhibited comparable growth performance to those fed FM protein based diet. Carcass composition of crude protein decreased significantly （P 〈_ 0.05） with increasing JM replacement level above 50%, while replacement 25% JM does not affect DM and Crude Protein of fish flesh. On the other hand, increasing JM replacement level up to 75% increased Ether Extract % significantly （P 〈 0.05） and increasing JM up to 100% increased ash content significantly （P ≤ 0.05） while energy content （EC） decreased. It could be concluded the replacement of 25% Jojoba meal instead of fishmeal in Nile tilapia fingerlings diets is possible without any adverse effects on its growth performance or feed utilization.展开更多
An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and...An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and feed utilization of Sebastes schlegeli. Six isonitrogenous and isoenergetic diets were formulated using fishmeal(FM, the control) as sole protein source, or proteins from five sources including poultry by-product meal(PBM), meat and bone meal(MBM), soybean meal(SBM), cottonseed meal(CSM) and canola meal(CNM). Fifteen percent of the crude protein provided by fish meal was replaced, respectively. The results showed that the differences in specific growth rate(SGR) and survival rate(SR) among fish fed PBM, MBM, SBM, CSM and whole FM diets were not significant. However, SGR and SR of fish fed CNM diet was significantly lower than that of other treatments. Feeding rate, feed conversion, nutrient retention showed similar patterns to that of growth. Fish fed CSM and CNM showed significantly lower apparent digestibility coefficient(ADC) of dry matter and gross energy than those fed others while fish fed CNM showed lower ADC of crude protein than those fed others(P<0.05). These results suggested that it was feasible to substitute 15% dietary protein provided by fishmeal with PBM, MBM, SBM and CSM, respectively, but not with CNM as the replacement with CNM reduced fish growth and feed utilization.展开更多
Poor palatability is a limiting factor for replacing fishmeal with other protein sources in aquaculture. The water-soluble molecules with low molecular weights are the major determinants of the palatability of diets. ...Poor palatability is a limiting factor for replacing fishmeal with other protein sources in aquaculture. The water-soluble molecules with low molecular weights are the major determinants of the palatability of diets. The present study was conducted to investigate the palatability of water-soluble extracts from single protein source(single extract pellets) and the mixture of these extracts with different proportions(blended extract pellets) in juvenile turbot(Scophthalmus maximus). Then according to the palatability of blended extract pellets, an optimal mixture proportion was selected, and a new protein source made from raw protein materials with the selected proportion was formulated to replace fishmeal. Summarily, the palatability of single extract pellets for turbot was descendent from fishmeal to pet-food grade poultry by-product meal, wheat gluten meal, soybean meal, peanut meal, meat and bone meal, and corn gluten meal. Subsequently, according to the palatability of single extract pellets, 52 kinds of blended extract pellets were designed to test their palatability. The results showed that the pellets presented remarkably different palatability, and the optimal one was diet 52(wheat gluten meal: pet-food grade poultry by-product meal: meat and bone meal: corn gluten meal = 1:6:1:2). The highest ingestion ratio(the number of pellets ingested/the number of pellets fed) was 0.73 ± 0.03, which was observed in Diet 52. Then five isonitrogenous(52% crude protein) and isocaloric(20 k J g^(-1) gross energy) diets were formulated by replacing 0(control), 35%, 50%, 65% and 80% of fishmeal with No.52 blending proportion. After a 10-weeks feeding trial, a consistent feed intake was found among all replacement treatments. Replacement level of fishmeal up to 35% did not significantly influence final body weight, specific growth rate, feed efficiency ratio, and protein efficiency ratio of turbot. Therefore, the water-soluble extracts of protein sources play an important role in improving the palatability of non-fishmeal protein sources in aquafeed.展开更多
An 8-week feeding trial was conducted to assess the effect of soybean meal （SBM）, groundnut meal （GNM） and blood meal （BM） addition in diets with or without （1%） fishmeal on the performance, N-digestibility an...An 8-week feeding trial was conducted to assess the effect of soybean meal （SBM）, groundnut meal （GNM） and blood meal （BM） addition in diets with or without （1%） fishmeal on the performance, N-digestibility and cost of production of growing grasscutters. Fifty-four grasscutters （9-week-old） of mixed sexes were randomly assigned to six dietary treatments, using a completely randomized design （CRD） in a 2 × 3 factorial arrangement, with three grasscutters per treatment and three replicates each. Treatments 1-3 （TI-T3） contained no fishmeal, whilst treatments 4-6 （T4-T6） had 1% fishmeal added. The diets were formulated to be isocaloric and isonitrogenous. N-digestibility was significantly high for SBM diets with or without fishmeal, 83.91% and 82.19%, respectively, followed by BM diets. Average daily gain （ADG） was significantly （P 〈 0.05） high （12.95 g） for BM diet without fishmeal. Feed cost per kg diet was the lowest （US$0.195） for the same BM diet. The results indicated that the inclusion of SBM and BM in the diet of grasscutters with or without 1% fishmeal could improve performance and it may be the most economical for feeding BM in the diet without fishmeal.展开更多
This study investigates the extent of the influence of imported fishmeal price changes on the market price of pisciculture products. To date, there have been only a few insufficient researches on this topic in Japan. ...This study investigates the extent of the influence of imported fishmeal price changes on the market price of pisciculture products. To date, there have been only a few insufficient researches on this topic in Japan. This paper aims to reveal the causality relationship between the market price of imported fishmeal and the market price of pisciculture products using the granger causality test, and to simulate the market price of pisciculture products using impulse response functions as the price of imported fishmeal increases. The results of the granger causality test and impulse response function analyses were as follows： （1） there is a market linkage from the price of imported fishmeal to the market price of sea bream, but no causality with the market price yellowtail; and （2） this has a positive impact on the market price of sea bream when the price of imported fishmeal changes. Moreover, spillover effects were noticed in this simple scenario （at a market price of 800 yen/kg and one unit shock of 1 yen） of about 3 yen/kg.展开更多
To trigger compensatory growth(CG)with novel protein sources in juvenile largemouth bass(Micropterus salmoides)(initial weight:4.73±0.04 g),Chlorella(Chlorella vulgaris,ChM),cottonseed protein concentrate(CSM),Cl...To trigger compensatory growth(CG)with novel protein sources in juvenile largemouth bass(Micropterus salmoides)(initial weight:4.73±0.04 g),Chlorella(Chlorella vulgaris,ChM),cottonseed protein concentrate(CSM),Clostridium autoethanogenum(CAP)and yellow mealworm(Tenebrio molitor,TM)were applied to completely substitute fishmeal in the diet during a four-week dietary restriction phase(the first phase).After being refed with fishmeal(FM)diet for the next four weeks(the second phase),the growth performance,proximate composition,biochemical parameters and liver condition of treatment groups(denoted as ChM,CSM,CAP,TM group,respectively)were assessed and compared with the control group(denoted as FM group),which was consistently fed with fishmeal diets.All groups exhibited different responses during restriction and refeeding phases.The CSM,CAP,and TM groups experienced initial growth reduction followed by accelerated growth,whereas the ChM group maintained steady growth.Compensation coefficient results indicated that only ChM and CSM groups achieved compensatory growth,although there was still a gap in final weight compared with FM group.Regarding the liver condition,histopathological analysis and biochemical parameters revealed a gradual increase in lipid accumulation in the FM group during the second phase,accompanied by slowing growth.The CSM,CAP,TM groups showed varying degrees of liver injury,with the CAP group exhibiting elevated serum transaminase(ALT and AST)activity and a dramatically higher content of malondialdehyde(MDA)in liver.Conversely,the ChM group possessed healthier livers,characterized by active antioxidative capacity and low content of total triglyceride(TG).Meanwhile,abnormal lipid deposition and different amino acid content were observed throughout the FM group,potentially affecting the fish quality compared with the ChM group.Overall,the results demonstrated the feasibility and potential of triggering compensatory growth by completely replacing fishmeal with Chlorella,which exhibited the showed superior performance among novel protein sources.展开更多
实验以异育银鲫"中科3号"幼鱼(3.2±0.5)g为实验对象,研究螺旋藻粉蛋白替代饲料鱼粉蛋白(0、20%、40%、60%、80%和100%)对鱼摄食、生长、饲料利用和蛋白沉积的影响。实验设计了6种等氮(38%)等脂(10%)等能(16.50 k J)的饲...实验以异育银鲫"中科3号"幼鱼(3.2±0.5)g为实验对象,研究螺旋藻粉蛋白替代饲料鱼粉蛋白(0、20%、40%、60%、80%和100%)对鱼摄食、生长、饲料利用和蛋白沉积的影响。实验设计了6种等氮(38%)等脂(10%)等能(16.50 k J)的饲料,每处理3个重复。采用室内循环水养殖系统,表观饱食投喂。实验水温为(28±3)℃,实验共持续60d。结果发现:随藻粉替代比例的增加,鱼摄食率显著上升;饲料效率则呈显著下降趋势;特定生长率在20%替代组与鱼粉组无显著差异(P>0.05),其他各替代组均显著低于鱼粉组(P<0.05);蛋白沉积率在20%、60%替代时与鱼粉组无显著差异(P>0.05),其他替代组显著低于鱼粉组(P<0.05);肥满度在各替代组均显著低于鱼粉组(P<0.05);鱼体蛋白随藻粉替代比例的增加呈现先持平后降低的趋势,鱼体脂肪则呈先降低后升高的变化;20%、40%和60%替代组全鱼灰分均高于全鱼粉组;肠道消化酶(胰蛋白酶、脂肪酶和α-淀粉酶)在替代组和对照组间均无显著差异(P>0.05);干物质表观消化率随藻粉蛋白替代比例的增加而呈显著上升,蛋白的表观消化率则呈显著下降趋势,总磷表观消化率在20%替代时最低,在100%替代时最高。综合特定生长率和蛋白沉积率情况,当鲫幼鱼饲料中鱼粉含量约为50%,且鱼粉为唯一蛋白源时,螺旋藻粉蛋白可替代饲料中20%鱼粉蛋白。展开更多
文摘A study was conducted to evaluate the effects of meat and bone meal （MBM） and poultry by-product meal （PBM） as the replacement of fishmeal in the diets on the growth performance, survival and apparent digestibility coefficient （ADC） of Japanese flounder （Paralichthys olivaceus）. The experimental diets included 0%, 20%, 40%, 60% and 80% MBM or PBM replacement of total fishmeal respectively. All diets were iso-nitrogenous and isocaloric. The results showed that there are no significant differences （P 〉0.05） in growth performance among the treatments fed with 0% -60% MBM replacement of fishmeal, while the percent weight gain （WG, % ）, body length gain （BLG, % ） and ADC significantly decrease when fishmeal is replaced by 80% MBM. The result showed also that there are no significant differences （P 〉0.05） in growth performance and ADC among all treatments fed with the diets with 0% -80% replacements of fishmeal with PBM.
基金This research was funded by AGER project“Fine Feed for Fish(4F)”lRif.nr.2016-01-01.Dr.Giulia Chemello was supported by a research grant of the University of Turin.
文摘Background:Recent investigations highlighted that Hermetia illucens(BSF)larva meal can be a valuable alternative protein source for aquafeed production.In this study,in substitution of fishmeal,we used increasing inclusion levels of a partially defatted BSF larva meal in low fishmeal-based diets for rainbow trout(Oncorhynchus mykiss Walbaum)and we evaluated the related implications in terms of growth performance,physical characteristics,proximate and fatty acid(FA)compositions of the fillets,gut and liver histology,and diet digestibility.In a 131-day trial,576 fish(100.1±9.29 g)were randomly allotted to 24 tanks(24 fish/tank,4 replicates/treatment).Six experimental diets were produced to have partial replacement of fishmeal(0,10%,20%,30%,40%and 50%)by increasing levels of BSF meal(0%[BSF0],3%[BSF3],6%[BSF6],9%[BSF9],12%[BSF12]and 15%[BSF15]on as fed basis,respectively).Results:No differences were observed among the treatments for all the considered growth performance parameters.The viscero and hepato-somatic indexes showed significant differences among the treatments,with the highest values observed in the BSF15 group.No differences were recorded in terms of fillet’s physical characteristics,dry matter(DM),crude protein(CP)and ether extract(EE)contents.Total saturated and monounsaturated FA increased,while polyunsaturated FA(particularly n-3 FA)decreased while increasing the HI meal inclusion in the diet.Histopathology of liver and gut was not affected,whereas,in posterior gut,villi were higher in BSF6 and BSF9 compared to BSF3 fish.The apparent digestibility of DM,CP,EE and gross energy did not vary among the treatments.Conclusions:These results suggest that a partially defatted BSF meal could be included up to 15%in low fishmeal-based diets for rainbow trout with no adverse effects on growth performance,fillet’s physical characteristics,gut and liver health,and diet digestibility.On the contrary,the fillet FA composition worsened while increasing the level of BSF meal in the diet.
文摘The present study was carried out to investigate the total and partial replacement of Jojoba meal （JM）, Simmondsia chinensis, with fishmeal （FM） at different levels （0%, 25%, 50%, 75%, and 100%） on growth performance, feed utilization, and carcass composition of Nile tilapia, Oreochromis niloticus fingerlings. Fingerlings with an average weight of 1.65 ± 0.01 g/fish stocked at a rate of 10 fish/aquarium for 84 days experimental period. All experimental diets were isocaloric （437.69 kcal/100 g Dry Matter, DM） and isonitrogenous （30.5% crude protein） and supplemented with 0.5% L-Methionine and 0.5% L-Lysine Hcl. Results showed that there were a significant differences （P 〈 0.05） in final body weights, average daily gain （g fish^-1 dayl）, specific growth rate （SGR, % day^-1）, feed conversion ratio （FCR）, protein efficiency ratio （PER）, protein productive value （PPV%） and energy retention （ER%） among the tested groups. Nile tilapia fingerlings fed on the diet containing 25% S. chinensis protein exhibited comparable growth performance to those fed FM protein based diet. Carcass composition of crude protein decreased significantly （P 〈_ 0.05） with increasing JM replacement level above 50%, while replacement 25% JM does not affect DM and Crude Protein of fish flesh. On the other hand, increasing JM replacement level up to 75% increased Ether Extract % significantly （P 〈 0.05） and increasing JM up to 100% increased ash content significantly （P ≤ 0.05） while energy content （EC） decreased. It could be concluded the replacement of 25% Jojoba meal instead of fishmeal in Nile tilapia fingerlings diets is possible without any adverse effects on its growth performance or feed utilization.
基金funded by National Key Basic Research Program (2009CB118702)partly by the Knowledge Innovation Program of the Chinese Academy of Sciences
文摘An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and feed utilization of Sebastes schlegeli. Six isonitrogenous and isoenergetic diets were formulated using fishmeal(FM, the control) as sole protein source, or proteins from five sources including poultry by-product meal(PBM), meat and bone meal(MBM), soybean meal(SBM), cottonseed meal(CSM) and canola meal(CNM). Fifteen percent of the crude protein provided by fish meal was replaced, respectively. The results showed that the differences in specific growth rate(SGR) and survival rate(SR) among fish fed PBM, MBM, SBM, CSM and whole FM diets were not significant. However, SGR and SR of fish fed CNM diet was significantly lower than that of other treatments. Feeding rate, feed conversion, nutrient retention showed similar patterns to that of growth. Fish fed CSM and CNM showed significantly lower apparent digestibility coefficient(ADC) of dry matter and gross energy than those fed others while fish fed CNM showed lower ADC of crude protein than those fed others(P<0.05). These results suggested that it was feasible to substitute 15% dietary protein provided by fishmeal with PBM, MBM, SBM and CSM, respectively, but not with CNM as the replacement with CNM reduced fish growth and feed utilization.
基金supported by Special Fund for Agroscientific Research in the Public Interest (201303053)Provincial Natural Science Foundation of Shandong (JQ201206) to G.H
文摘Poor palatability is a limiting factor for replacing fishmeal with other protein sources in aquaculture. The water-soluble molecules with low molecular weights are the major determinants of the palatability of diets. The present study was conducted to investigate the palatability of water-soluble extracts from single protein source(single extract pellets) and the mixture of these extracts with different proportions(blended extract pellets) in juvenile turbot(Scophthalmus maximus). Then according to the palatability of blended extract pellets, an optimal mixture proportion was selected, and a new protein source made from raw protein materials with the selected proportion was formulated to replace fishmeal. Summarily, the palatability of single extract pellets for turbot was descendent from fishmeal to pet-food grade poultry by-product meal, wheat gluten meal, soybean meal, peanut meal, meat and bone meal, and corn gluten meal. Subsequently, according to the palatability of single extract pellets, 52 kinds of blended extract pellets were designed to test their palatability. The results showed that the pellets presented remarkably different palatability, and the optimal one was diet 52(wheat gluten meal: pet-food grade poultry by-product meal: meat and bone meal: corn gluten meal = 1:6:1:2). The highest ingestion ratio(the number of pellets ingested/the number of pellets fed) was 0.73 ± 0.03, which was observed in Diet 52. Then five isonitrogenous(52% crude protein) and isocaloric(20 k J g^(-1) gross energy) diets were formulated by replacing 0(control), 35%, 50%, 65% and 80% of fishmeal with No.52 blending proportion. After a 10-weeks feeding trial, a consistent feed intake was found among all replacement treatments. Replacement level of fishmeal up to 35% did not significantly influence final body weight, specific growth rate, feed efficiency ratio, and protein efficiency ratio of turbot. Therefore, the water-soluble extracts of protein sources play an important role in improving the palatability of non-fishmeal protein sources in aquafeed.
文摘An 8-week feeding trial was conducted to assess the effect of soybean meal （SBM）, groundnut meal （GNM） and blood meal （BM） addition in diets with or without （1%） fishmeal on the performance, N-digestibility and cost of production of growing grasscutters. Fifty-four grasscutters （9-week-old） of mixed sexes were randomly assigned to six dietary treatments, using a completely randomized design （CRD） in a 2 × 3 factorial arrangement, with three grasscutters per treatment and three replicates each. Treatments 1-3 （TI-T3） contained no fishmeal, whilst treatments 4-6 （T4-T6） had 1% fishmeal added. The diets were formulated to be isocaloric and isonitrogenous. N-digestibility was significantly high for SBM diets with or without fishmeal, 83.91% and 82.19%, respectively, followed by BM diets. Average daily gain （ADG） was significantly （P 〈 0.05） high （12.95 g） for BM diet without fishmeal. Feed cost per kg diet was the lowest （US$0.195） for the same BM diet. The results indicated that the inclusion of SBM and BM in the diet of grasscutters with or without 1% fishmeal could improve performance and it may be the most economical for feeding BM in the diet without fishmeal.
文摘This study investigates the extent of the influence of imported fishmeal price changes on the market price of pisciculture products. To date, there have been only a few insufficient researches on this topic in Japan. This paper aims to reveal the causality relationship between the market price of imported fishmeal and the market price of pisciculture products using the granger causality test, and to simulate the market price of pisciculture products using impulse response functions as the price of imported fishmeal increases. The results of the granger causality test and impulse response function analyses were as follows： （1） there is a market linkage from the price of imported fishmeal to the market price of sea bream, but no causality with the market price yellowtail; and （2） this has a positive impact on the market price of sea bream when the price of imported fishmeal changes. Moreover, spillover effects were noticed in this simple scenario （at a market price of 800 yen/kg and one unit shock of 1 yen） of about 3 yen/kg.
基金funded by the National Key Research and Development Program of China(2023YFD2400600).
文摘To trigger compensatory growth(CG)with novel protein sources in juvenile largemouth bass(Micropterus salmoides)(initial weight:4.73±0.04 g),Chlorella(Chlorella vulgaris,ChM),cottonseed protein concentrate(CSM),Clostridium autoethanogenum(CAP)and yellow mealworm(Tenebrio molitor,TM)were applied to completely substitute fishmeal in the diet during a four-week dietary restriction phase(the first phase).After being refed with fishmeal(FM)diet for the next four weeks(the second phase),the growth performance,proximate composition,biochemical parameters and liver condition of treatment groups(denoted as ChM,CSM,CAP,TM group,respectively)were assessed and compared with the control group(denoted as FM group),which was consistently fed with fishmeal diets.All groups exhibited different responses during restriction and refeeding phases.The CSM,CAP,and TM groups experienced initial growth reduction followed by accelerated growth,whereas the ChM group maintained steady growth.Compensation coefficient results indicated that only ChM and CSM groups achieved compensatory growth,although there was still a gap in final weight compared with FM group.Regarding the liver condition,histopathological analysis and biochemical parameters revealed a gradual increase in lipid accumulation in the FM group during the second phase,accompanied by slowing growth.The CSM,CAP,TM groups showed varying degrees of liver injury,with the CAP group exhibiting elevated serum transaminase(ALT and AST)activity and a dramatically higher content of malondialdehyde(MDA)in liver.Conversely,the ChM group possessed healthier livers,characterized by active antioxidative capacity and low content of total triglyceride(TG).Meanwhile,abnormal lipid deposition and different amino acid content were observed throughout the FM group,potentially affecting the fish quality compared with the ChM group.Overall,the results demonstrated the feasibility and potential of triggering compensatory growth by completely replacing fishmeal with Chlorella,which exhibited the showed superior performance among novel protein sources.
文摘实验以异育银鲫"中科3号"幼鱼(3.2±0.5)g为实验对象,研究螺旋藻粉蛋白替代饲料鱼粉蛋白(0、20%、40%、60%、80%和100%)对鱼摄食、生长、饲料利用和蛋白沉积的影响。实验设计了6种等氮(38%)等脂(10%)等能(16.50 k J)的饲料,每处理3个重复。采用室内循环水养殖系统,表观饱食投喂。实验水温为(28±3)℃,实验共持续60d。结果发现:随藻粉替代比例的增加,鱼摄食率显著上升;饲料效率则呈显著下降趋势;特定生长率在20%替代组与鱼粉组无显著差异(P>0.05),其他各替代组均显著低于鱼粉组(P<0.05);蛋白沉积率在20%、60%替代时与鱼粉组无显著差异(P>0.05),其他替代组显著低于鱼粉组(P<0.05);肥满度在各替代组均显著低于鱼粉组(P<0.05);鱼体蛋白随藻粉替代比例的增加呈现先持平后降低的趋势,鱼体脂肪则呈先降低后升高的变化;20%、40%和60%替代组全鱼灰分均高于全鱼粉组;肠道消化酶(胰蛋白酶、脂肪酶和α-淀粉酶)在替代组和对照组间均无显著差异(P>0.05);干物质表观消化率随藻粉蛋白替代比例的增加而呈显著上升,蛋白的表观消化率则呈显著下降趋势,总磷表观消化率在20%替代时最低,在100%替代时最高。综合特定生长率和蛋白沉积率情况,当鲫幼鱼饲料中鱼粉含量约为50%,且鱼粉为唯一蛋白源时,螺旋藻粉蛋白可替代饲料中20%鱼粉蛋白。
