饲粮精氨酸水平对31~60日龄黄羽肉鸡生长性能、胴体品质和养分表观代谢率的影响

Effects of Dietary Arginine Level on Growth Performance,Carcass Quality and Nutrient Apparent Metabolic Rates of Yellow⁃Feathered Chickens Aged from 31 to 60 Days

本试验旨在研究饲粮精氨酸水平对31~60日龄中速型黄羽肉鸡生长性能、胴体品质、血浆生化指标、肠道形态和养分表观代谢率等的影响,以确定其精氨酸需要量。试验选用1200羽31日龄中速型黄羽肉鸡母鸡,根据体重一致的原则随机分为6组,每组8个重复,每个重复25只鸡。各组分别饲喂在基础饲粮中添加0、0.05%、0.10%、0.15%、0.20%、0.25%L-精氨酸的饲粮,即各组饲粮精氨酸水平分别为0.85%、0.90%、0.95%、1.00%、1.05%和1.10%。试验期30 d。结果表明:1)0.85%和1.05%精氨酸组黄羽肉鸡平均日采食量显著高于1.00%精氨酸组(P<0.05);1.05%精氨酸组平均日增重最高,显著高于0.85%和1.00%精氨酸组(P<0.05)。与基础饲粮相比,饲粮中添加精氨酸显著降低黄羽肉鸡料重比(P<0.05),且料重比随饲粮精氨酸水平的提高呈线性和二次变化(P<0.05)。2)饲粮精氨酸水平显著影响黄羽肉鸡屠宰率、半净膛率和全净膛率(P<0.05),但对胸肌率、腿肌率和腹脂率均无显著影响(P>0.05)。3)饲粮精氨酸水平显著影响黄羽肉鸡血浆一氧化氮(NO)含量(P<0.05),对血浆诱导型一氧化氮合酶(iNOS)活性无显著影响(P>0.05)。其中,0.90%、0.95%、1.00%和1.05%精氨酸组血浆NO含量显著高于1.10%精氨酸组(P<0.05)。4)饲粮精氨酸水平对黄羽肉鸡消化器官指数和养分表观代谢率无显著影响(P>0.05)。5)0.95%精氨酸组黄羽肉鸡空肠绒毛高度最高,显著高于0.85%、0.90%、1.05%和1.10%精氨酸组(P<0.05),且空肠绒毛高度随饲粮精氨酸水平的提高呈二次变化(P<0.05)。综上所述,饲粮中添加适宜水平精氨酸可以提高黄羽肉鸡生长性能,改善肠道形态。以料重比为评定指标,通过单斜率折线分析得出,31~60日龄中速型黄羽肉鸡母鸡饲粮适宜精氨酸水平为0.96%,每日精氨酸需要量为0.962 g/d,饲粮标准回肠可消化(SID)精氨酸水平分别为0.86%,每日SID精氨酸需要量为0.861 g/d。

This experiment was conducted to investigate the effects of dietary arginine level on growth perform-ance,carcass quality,plasma biochemical indices,intestinal morphology and nutrient apparent metabolic rates of medium-speed yellow-feathered chickens aged from 31 to 60 days,and to determine the arginine require-ment.A total of 1200 female medium-speed yellow-feathered chickens of 31-day-old were randomly divided into 6 groups with 8 replicates per group and 25 chickens per replicate according to the principle of similar body weight.The chickens in each group were fed a basal diet supplemented with 0,0.05%,0.10%,0.15%,0.20%and 0.25%L-arginine,which mean the dietary arginine level in each group was 0.85%,0.90%,0.95%,1.00%,1.05%and 1.10%,respectively.The experiment lasted for 30 days.The results showed as follows:1)the average daily feed intake of yellow-feathered chickens in 0.85%and 1.05%arginine groups was significantly higher than that in 1.00%arginine group(P<0.05);the average daily gain in 1.05%argi-nine group was the highest,and significantly higher than that in 0.85%and 1.00%arginine groups(P<0.05).Compared with the basal diet,dietary arginine supplementation significantly decreased the feed to gain ratio of yellow-feathered chickens(P<0.05),and the feed to gain ratio had linear and quadratic changes with the in-crease of dietary arginine level(P<0.05).2)Dietary arginine level significantly affected the dressing percent-age,half-eviscerated yield percentage and eviscerated yield percentage of yellow-feathered chickens(P<0.05),but had no significant effects on the breast muscle percentage,thigh muscle percentage and abdominal fat percentage(P>0.05).3)Dietary arginine level significantly affected the plasma nitric oxide(NO)content of yellow-feathered chickens(P<0.05),but had no significant effect on the plasma inducible nitric oxide syn-thase(iNOS)activity(P>0.05).The plasma NO content in 0.90%,0.95%,1.00%and 1.05%arginine groups was significantly higher than that in 1.10%arginine group(P<0.05).4)Dietary arginine level had no significant effects on digestive organ indices and nutrient apparent metabolic rates of yellow-feathered chickens(P>0.05).5)The villus height in jejunum of yellow-feathered chickens in 0.95%arginine group was the highest,which was significantly higher than that in 0.85%,0.90%,1.05%and 1.10%arginine groups(P<0.05),and the villus height in jejunum had a quadratic change with the increase of dietary arginine level(P<0.05).In conclusion,dietary supplementation with appropriate level of arginine can improve the growth per-formance and intestinal morphology of yellow-feathered chickens.Based on the feed to gain ratio as the evalua-tion index,the one-slope broken-line analysis results show that the optimal dietary arginine level for female me-dium-speed yellow-feathered chickens aged from 31 to 60 days is 0.96%,the daily arginine requirement is 0.962 g/d,the dietary standard ileum digestible(SID)arginine level is 0.86%,and the daily SID arginine re-quirement is 0.861 g/d.