补充微囊赖氨酸和蛋氨酸对草鱼生长性能的影响

Effects of Microcapsule Lysine and Methionine Supplementation on Growth Performance of Grass Crap (Ctenopharyngodon idellus)

为了探讨微囊赖氨酸和微囊蛋氨酸对草鱼生长性能的影响,在草鱼基础饲料中分别添加0(对照)、0.2%微囊赖氨酸、0.3%微囊赖氨酸、0.4%微囊赖氨酸、0.15%微囊赖氨酸+0.15%微囊蛋氨酸、0.2%微囊蛋氨酸,饲喂初始平均体重(62.70±0.89)g的草鱼97d。试验结果表明:除0.2%和0.4%微囊赖氨酸组,其他添加微囊氨基酸组的特定生长率(SGR)均高于对照组(P>0.05);除0.4%微囊赖氨酸组,其他添加微囊氨基酸组的饲料系数(FCR)均低于对照组(P>0.05)。添加微囊氨基酸组的蛋白质沉积率(PDR)均高于对照组(P>0.05),肝体比(P>0.05或P<0.05)和脏体比(P>0.05)都小于对照组,肌肉和肝胰脏的粗蛋白质含量均高于对照组(P>0.05或P<0.05)。结果提示:1)草鱼饲料中添加微囊氨基酸可促进草鱼生长,降低饲料系数,提高蛋白质沉积率,但微囊赖氨酸添加过量会使草鱼生长减慢,添加0.3%微囊赖氨酸最为适宜;2)饲料中添加微囊氨基酸可降低草鱼肝体比和脏体比,提高肌肉和肝胰脏的蛋白质含量。

The experiment was conducted to study the effects of microcapsule lysine （Lys） and methionine （Met） on the growth performance of grass carp （Ctenopharyngodon idellus）. The grass carps with an average body weight of （62.7±0.89） g were fed with the basal feeds added with 0,0.2% microcapsule Lys,0.3% microcapsule Lys,0.4% microcapsules Lys,0.15% microcapsule Lys＋0.15% microcapsule Met,and 0.2% microcapsule Met for 97 days,respectively. The results showed that the specific growth rates （P〉0.05） of the microcapsule amino acid groups were higher than that of control group except for 0.2% and 0.4% microcapsule Lys groups; the feed coefficient ratios （P〉0.05） of the microcapsule amino acid groups were lower than that of control group except for 0.4% microcapsule Lys group. The protein deposition rate （P〈0.05） of the microcapsule amino acid groups were increased compared with control group,as well as the crude protein content of muscle and hepatopancreas （P〉0.05 or P〈0.05）. The liver to body ratio （P〉0.05 or P〈0.05） and the gut to body ratio （P〈0.05） of the microcapsule amino acid groups were lower than that of control group. The results indicated as follows： 1） adding with microcapsule amino acids to feeds of grass carp could improve the growth of grass carp,decrease feed conversion ratio,increase the protein deposition rate,but adding excess microcapsule Lys slowed down the growth of grass carp,and 0.3% microcapsule Lys supplementation was the optimum; 2） adding microcapsule amino acids to feeds could decrease the liver to body ratio and the gut to body ratio of the grass carp,and improve the protein content in muscle and hepatopancreas.