Cottonseed meal(CM) was used at up to 36.95% content in the diet(replacing 60% of dietary fish meal protein) without any negative effects on growth performance of pre-adult grass carp(initial body weight,761 g) under ...Cottonseed meal(CM) was used at up to 36.95% content in the diet(replacing 60% of dietary fish meal protein) without any negative effects on growth performance of pre-adult grass carp(initial body weight,761 g) under outdoor conditions.A culture trial was conducted in net cages installed in a large concrete pond.Seven isonitrogenous and isoenergetic diets containing a gradient of CM concentrations(0,12.2%,24.4%,36.6%,48.8%,54.8%,and 61.0%) as replacement for dietary fish meal protein(0,20%,40%,60%,80%,90%,and 100%) were formulated.Dietary non-resistant starch(from maize) was inverse to dietary CM.Growth performance and feed utilization of fish fed the diets containing CM replacing 0-40% fishmeal protein were not affected after the 6-week feeding trial.Accumulation of hepatopancreatic total gossypol in the hepatopancreas was significantly correlated with free gossypol content in the diets(HTG=88.6+1.5×DFG,R^2=0.89,P<0.05).Intestinal a-amylase and γ-glutamyl transpeptidase activities rose along with increasing dietary CM level.The structure of the mid-intestinal tissues and the ultrastructure of the enterocyte microvilli were normal when dietary CM was <36.6%(60% protein replacement).Increasing dietary CM content increased serum alanine aminotransferase levels but decreased serum alkaline phosphatase,cholesterol,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol,triglycerides,and albumin(P<0.05).展开更多
基金Supported by the Modern Agro-Industry Technology Research System(No.CARS-46-19)the Special Fund for Agro-Scientific Research in the Public Interest(No.201303053)+2 种基金the National Basic Research Program of China(973 Program)(No.2014CB138602)the National Natural Science Foundation of China(No.31101908)the Fund Project in the State Key Laboratory of Freshwater Ecology and Biotechnology(No.2014FBZ04)
文摘Cottonseed meal(CM) was used at up to 36.95% content in the diet(replacing 60% of dietary fish meal protein) without any negative effects on growth performance of pre-adult grass carp(initial body weight,761 g) under outdoor conditions.A culture trial was conducted in net cages installed in a large concrete pond.Seven isonitrogenous and isoenergetic diets containing a gradient of CM concentrations(0,12.2%,24.4%,36.6%,48.8%,54.8%,and 61.0%) as replacement for dietary fish meal protein(0,20%,40%,60%,80%,90%,and 100%) were formulated.Dietary non-resistant starch(from maize) was inverse to dietary CM.Growth performance and feed utilization of fish fed the diets containing CM replacing 0-40% fishmeal protein were not affected after the 6-week feeding trial.Accumulation of hepatopancreatic total gossypol in the hepatopancreas was significantly correlated with free gossypol content in the diets(HTG=88.6+1.5×DFG,R^2=0.89,P<0.05).Intestinal a-amylase and γ-glutamyl transpeptidase activities rose along with increasing dietary CM level.The structure of the mid-intestinal tissues and the ultrastructure of the enterocyte microvilli were normal when dietary CM was <36.6%(60% protein replacement).Increasing dietary CM content increased serum alanine aminotransferase levels but decreased serum alkaline phosphatase,cholesterol,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol,triglycerides,and albumin(P<0.05).
