精氨酸和赖氨酸对瓦氏黄颡鱼幼鱼生长和非特异性免疫力的影响

摘要

以初始体质量(2.12±0.01)g的瓦氏黄颡鱼为研究对象,在室内流水系统中进行为期56 d的摄食生长实验,探讨饲料中精氨酸、赖氨酸水平及其交互作用对瓦氏黄颗鱼幼鱼生长和非特异性免疫力的影响.采用3x3双因子实验设计,制作9种Arg和Lys不同配比的饲料(粗蛋白42%、粗脂肪10%),其中Arg水平为2.41%、4.86%和6.81%(饲料蛋白),在每个Arg水平分别设1.95%,5.84%和8.27%(饲料蛋白)3个Lys水平.每种饲料随机投喂3桶(养殖桶规格:40L),每桶30尾实验鱼.实验结果表明,饲料中Arg、Lys水平对瓦氏黄颗鱼生长和头肾巨噬细胞呼吸爆发活性均有显著影响(P<0.05),当Arg/Lys为6.81/5.84(饲料蛋白)时,实验鱼生长最佳,而头肾巨噬细胞活性最高值出现在Arg/Lys为4.86/8.27(饲料蛋白)水平.饲料中Arg水平对瓦氏黄颡鱼血清一氧化氮合酶(NOS)活性有显著影响(P<0.05),且在适中和高Arg水平时,血清NOS活性均高于低水平Arg组.饲料中Arg,Lys水平对血清精氨酸酶(ARG)活性和过氧化氢酶(CAT)活性无显著影响(P>0.05).饲料中Arg和Lys对瓦氏黄颗鱼的生长存在交互作用,而对体组成、肝指数、头肾巨噬细胞呼吸爆发活性、血清中NOS,ARG和CAT活性均无交互作用.%An 8-week feeding trial was conducted to estimate the effects of dietary arginine(Arg)and lysine (Lys)on growth and non-specific immune responses of juvenile darkbarbel catfish. Nine diets(42% crude protein and 10% crude lipid) were formulated to contain three Arg levels(2. 41% ,4. 86% and 6. 81% of dietary protein) ,and each with three Lys levels( 1.95% ,5.84% and 8. 27% of dietary protein). Each diet was randomly fed to triplicate groups of darkbarbel catfish [initial body weight; (2.12 ±0.01) g]to apparent satiation and each group was stocked with 30 fish. At the termination of the feeding trial,growth and nonspecific immune parameters were monitored. The results showed dietary arginine and lysine had significant effects on the specific growth rate (SGR) and the respiratory burst activity of head kidney macrophages of juvenile darkbarbel catfish (P < 0. 05). The appropriate content of diet arginine/lysine was 6. 81/5. 84 dietary protein based on the growth, but the respiratory burst activity of headkidney macrophages was the highest when arginine/lysine was 4.86/8.27 dietary protein. Dietary Arg had significant effects on the serum nitricoxide synthase(NOS) activity of juvenile darkbarbel catfish (P <0.05). The activity of NOS was higher in fish fed appropriate or high Arg levels than low Ary levels. No significant differences were found in the serum arginase ( ARG) and catalase ( CAT) ( P > 0. 05) among dietary treatments. In the present study, significant interactions of dietary arginine and lysine were found on growth of juvenile darkbarbel catfish, but not on the body composition,hepatosomatic index(HIS) ,and serum NOS,ARG and CAT activity.