Protease as feed additive is being used in poultry production as a partial replacement for protein sources for cost efficiency and reducing nitrogen excretion. However, diverse proteases may yield different responses ...Protease as feed additive is being used in poultry production as a partial replacement for protein sources for cost efficiency and reducing nitrogen excretion. However, diverse proteases may yield different responses under field conditions. A pellet diet study was conducted in Cobb broilers to assess the impact of coated compound （CC） and mono-component （MC） proteases with 5% replacement of digestible amino acids and 0.9% crude protein. Birds fed positive control diet had a better growth than those fed negative control diet, regardless of enzyme supplementation. However, CC protease had shown feed conversion ratio （FCR） like control in a reformulated diet, whereas negative control and MC protease missed to gain the feed conversion. In measures of nutritional efficiency, like energy efficiency, protein efficiency and amino acids efficiency （lysine and methionine）, the CC protease proved to be better than MC protease. In terms of European efficiency factor （EEF）, control and CC protease elicited a closer response, whereas the other two groups showed a drop. In this study, CC protease allowed partial substitution of digestible amino acids and crude protein, while maintaining feed efficiency and animal performance. It could be concluded that incorporating CC proteases is an efficient choice to maximize the utilization feed material resources and efficiency in animal protein production.展开更多
An 8-week trial was conducted to investigate graded levels of dietary LPC on growth,apparent digestibility(ADs)of nutrients and lipid metabolism in juvenile turbot Scophthalmus maximus L.Five experimental diets were f...An 8-week trial was conducted to investigate graded levels of dietary LPC on growth,apparent digestibility(ADs)of nutrients and lipid metabolism in juvenile turbot Scophthalmus maximus L.Five experimental diets were formulated which contain 11%crude fat with graded amounts of LPC(0,1000,2500,4000,5500 mg/kg diet).The fish fed diet with 11%crude lipid and 0 LPC was used as the negative control group(C-),meanwhile the fish fed diet with 12%crude fat and 0 LPC was used as the positive control group(C+).Each diet was fed to triplicate groups of turbot(initial body weight of 41 g)for 56d.Weight gain rate and specific growth rate of the fish fed LPC supplemented diets were significantly higher than the control groups,and the growth performance of the C-group was significantly lower than the others.The viscerosomatic index(VSI)was significantly decreased and the gall bladder somatic index(GSI)was significantly increased by dietary LPC.Crude lipid contents of muscle were elevated by dietary LPC.Apparent digestibility of energy was decreased by dietary LPC,but protein and lipid were not affected.Both total cholesterol(T-CHO)and high density lipoprotein cholesterol(HDL-C)were up-regulated,meanwhile neither alanine aminotransferase(ALT)nor total protein(TP)were down-regulated by dietary LPC.Enzymes involved in lipid metabolism(total lipase,hepatic lipase,lipoprotein lipase,fatty acids synthase,and lipase)were all elevated by dietary LPC.In conclusion,the lipid requirements of turbot were decreased by dietary LPC and the lipid utilization coefficient was enhanced.Based on SAS NLIN regression,dietary 870.37 mg/kg LPC was appropriate for turbot juvenile.展开更多
文摘Protease as feed additive is being used in poultry production as a partial replacement for protein sources for cost efficiency and reducing nitrogen excretion. However, diverse proteases may yield different responses under field conditions. A pellet diet study was conducted in Cobb broilers to assess the impact of coated compound （CC） and mono-component （MC） proteases with 5% replacement of digestible amino acids and 0.9% crude protein. Birds fed positive control diet had a better growth than those fed negative control diet, regardless of enzyme supplementation. However, CC protease had shown feed conversion ratio （FCR） like control in a reformulated diet, whereas negative control and MC protease missed to gain the feed conversion. In measures of nutritional efficiency, like energy efficiency, protein efficiency and amino acids efficiency （lysine and methionine）, the CC protease proved to be better than MC protease. In terms of European efficiency factor （EEF）, control and CC protease elicited a closer response, whereas the other two groups showed a drop. In this study, CC protease allowed partial substitution of digestible amino acids and crude protein, while maintaining feed efficiency and animal performance. It could be concluded that incorporating CC proteases is an efficient choice to maximize the utilization feed material resources and efficiency in animal protein production.
基金We all thank Kemin Industries(Zhuhai)Co.Ltd for supplying LPC and supporting many advices for the trial.The work was supported by key research and development Plan of Shandong Province(2016GSF115005)Technology Development Plan Project of Shandong Province(2014GHY115006).
文摘An 8-week trial was conducted to investigate graded levels of dietary LPC on growth,apparent digestibility(ADs)of nutrients and lipid metabolism in juvenile turbot Scophthalmus maximus L.Five experimental diets were formulated which contain 11%crude fat with graded amounts of LPC(0,1000,2500,4000,5500 mg/kg diet).The fish fed diet with 11%crude lipid and 0 LPC was used as the negative control group(C-),meanwhile the fish fed diet with 12%crude fat and 0 LPC was used as the positive control group(C+).Each diet was fed to triplicate groups of turbot(initial body weight of 41 g)for 56d.Weight gain rate and specific growth rate of the fish fed LPC supplemented diets were significantly higher than the control groups,and the growth performance of the C-group was significantly lower than the others.The viscerosomatic index(VSI)was significantly decreased and the gall bladder somatic index(GSI)was significantly increased by dietary LPC.Crude lipid contents of muscle were elevated by dietary LPC.Apparent digestibility of energy was decreased by dietary LPC,but protein and lipid were not affected.Both total cholesterol(T-CHO)and high density lipoprotein cholesterol(HDL-C)were up-regulated,meanwhile neither alanine aminotransferase(ALT)nor total protein(TP)were down-regulated by dietary LPC.Enzymes involved in lipid metabolism(total lipase,hepatic lipase,lipoprotein lipase,fatty acids synthase,and lipase)were all elevated by dietary LPC.In conclusion,the lipid requirements of turbot were decreased by dietary LPC and the lipid utilization coefficient was enhanced.Based on SAS NLIN regression,dietary 870.37 mg/kg LPC was appropriate for turbot juvenile.
