饲料中鸡肉粉替代鱼粉、磷脂油替代鱼油对中成阶段线鳢生长、饲料利用和体组成的影响OA北大核心CSTPCD

To investigate the optimal fishmeal and fish oil replacement levels in grow-out stage snakehead(initial body mass 150 g),Channa striata,we first explored the optimal fishmeal replacement level by substituting 0%,17%,33%,50%,67%,and 83%of fishmeal 65(65%-protein fishmeal)with poultry meal respectively,resulting in six iso-nitrogenous and iso-lipidic experimental diets.The diets were fed to fish to apparent satiation twice daily for 8 weeks.Subsequently,we evaluated the optimal level of fish oil substitution by replacing 0%,13%,25%,38%,50%,and 63%of fish oil with soy lecithin,resulting in six iso-nitrogenous and iso-lipidic experimental diets.The diets were also fed to fish to apparent satiation twice daily for 8 weeks.Results showed replacing fishmeal 65 with poultry meal had no significant effects on the growth performance,body indices,nutrient apparent digestibility,or body composition of snakehead fish(P>0.05).Substituting fish oil with soy lecithin did not significantly influence the growth performance,body indices,or body composition of the fish(P>0.05),nor did it affect the apparent digestibility of dry matter and crude protein(P>0.05);however,a minor significant reduction in the apparent digestibility of crude lipids(～2%)was observed when fish oil substitution levels reached or exceeded 38%(P<0.05).Results on growth,feed utilization,and body composition indicate that poultry meal can replace up to 83%of fishmeal 65 and soy lecithin up to 63%of fish oil in diets for grow-out stage snakehead.This study fills the research gap in the substitution of fishmeal and fish oil during the grow-out phase of Channa striata,offering valuable data for optimizing commercial feed composition and reducing costs.