L-组氨酸对肉鸡生长性能、肌肉品质、血浆抗氧化能力和肌肉咪唑二肽含量的影响

摘要

This experiment was conducted to study the effects of dietary supplementation of L-histidine on growth performance, meat quality, plasma antioxidant capacity and meat imidazole dipeptide content of broil-ers. A total of 300 one-day-old male Arbor Acres ( AA) broilers were randomly allotted into 5 groups with 6 replicates per group and 10 broilers per replicate. The control group was fed a basal diet, and the experimental groups were fed the basal diet supplemented with 250, 500, 1000, 2000 mg/kg L-histidine, respectively. The trial lasted for 42 days. The results showed as follows:1) feed to gain ratio was decreased by L-histidine of boilers at late growing phase ( 22 to 42 days of age) , and 250 and 2000 mg/kg groups were significantly lower than the control group (P<0.05). 2) Dietary L-histidine supplementation had no significant effects on dressing percentage, breast muscle rate, leg muscle rate, abdominal fat rate, drip loss, shear force and pH of muscle ( P>0.05) . 3) At 42 days of age, total antioxidant capacity, the activities of the glutathione peroxidase and total superoxide dismutase in plasma were increased linearly with the supplemental level of L-histidine in di-ets ( P<0.05) . 4) At 42 days of age, the contents of carnosine and anserine of muscle were increased by L-histidine supplementation, the content of carnosine was increased by 40. 58%, 42. 75% and 33. 70% in 500, 1000 and 2000 mg/kg groups ( P<0.05) , respectively, and the content of anserine was increased by 37.80%in 1000 mg/kg group ( P<0.05);imidazole dipeptide contents reached the highest when the supplemental lev-el of L-histidine was 1276 mg/kg according to quadratic formulas between them. In conclusion, dietary L-his-tidine supplementation can increase feed conversion rate, improve plasma antioxidant capacity and increase con-tents of imidazole dipeptides of muscle in broilers, and the proper supplemental level in diet of L-histidine in di-et is 1000 to 2000 mg/kg under the conditions in the current study. Considering imidazole dipeptide content in muscle, the optimal supplemental level in diet is 1276 mg/kg.%本试验旨在研究饲粮添加L-组氨酸对肉鸡生长性能、肌肉品质、血浆抗氧化能力和肌肉咪唑二肽含量的影响.选取体重相近、健康的1日龄爱拔益加(AA)肉仔鸡公雏300只,随机分为5组,每组6个重复,每个重复10只鸡.对照组饲喂基础饲粮,试验组饲喂在基础饲粮中分别添加250、500、1000、2000 mg/kg L-组氨酸的试验饲粮.试验期42 d.结果表明:1)L-组氨酸降低了肉鸡生长后期(22~42日龄)的料重比,250和2000 mg/kg添加组显著低于对照组(P<0.05).2)L-组氨酸对肌肉全净膛率、胸肌率、腿肌率、腹脂率、滴水损失、剪切力和pH无显著影响(P>0.05).3)L-组氨酸线性提高了42日龄血浆总抗氧化能力及谷胱甘肽过氧化物酶、总超氧化物歧化酶的活性(P<0.05).4)L-组氨酸增加了42日龄肌肉中肌肽和鹅肌肽含量,500、1000和2000 mg/kg添加组肌肽含量分别较对照组升高了40.58%、42.75%、33.70%(P<0.05),1000 mg/kg添加组鹅肌肽含量较对照组增加了37.80%(P<0.05);对肌肉中肌肽和鹅肌肽含量进行二次曲线方程拟合表明,L-组氨酸添加量为1276 mg/kg时,肌肉咪唑二肽含量最高.可见,饲粮添加L-组氨酸可提高肉鸡的饲料转化率,改善血浆抗氧化能力,增加肌肉中咪唑二肽含量.本试验条件下,饲粮添加1000~2000 mg/kg L-组氨酸较佳.从增加肌肉咪唑二肽含量考虑,饲粮L-组氨酸适宜添加量为1276 mg/kg