脂多糖(LPS)刺激对肉仔鸡生产性能及肌肉品质影响

Effect of lipopolysaccharide(LPS) challenge on performance and meat quality of broiler chickens

为确证免疫刺激对肉仔鸡生产性能及肌肉品质的影响,取108只1周龄肉仔鸡,均分为2个组,对照组(CK)和脂多糖(LPS)组。LPS组每周1、3、5按500μg/kg BW腹腔注射LPS,对照组注射等量生理盐水,8～21日龄连续2周。21日龄时,测定生产性能及血液皮质酮及IL-1β水平。42日龄时,测生产性能,胸肌率、腿肌(带骨)率、腹脂率;胸肌及腿肌pH,滴水损失率和肌肉剪切力;胸肌中的蛋白质、脂肪含量、蛋白脂肪比及胸肌纤维面积。结果表明,LPS刺激对肉仔鸡血液皮质酮及IL-1β含量,前期及全期生产性能没有显著影响(P>0.05)。LPS组肉仔鸡腹脂率及胸肌蛋白脂肪比分别比对照组高17.81%和36.94%,而胸肌pH比对照组低2.23%,均差异显著(P<0.05)。结果显示:免疫刺激尽管对肉仔鸡生产性能没有显著影响,但对胴体品质,胸肌肌肉品质均会产生不良影响。

To test the effect of immunological challenge on performance and meat quality of broiler chickens,108 7-d broiler chickens were divided into control group（CK） and experimental group（LPS）.Birds in LPS group were injected with 500 μg/kg BW LPS dissolved in saline on Monday,Wednesday and Friday since 8-d of age for continuous 2 weeks,meanwhile,birds in CK were injected with saline.The performance and serum corticosterone and IL-1β level of broiler chickens were evaluated on 21-d.The performance,percentage of pectoralis and thigh muscle（with bone） and abdominal fat;the drip loss rate,pH value and shear force of pectoralis and thigh muscle;the protein and fat content,protein/fat ratio and myofiber area of pectoralis of broiler chickens were assayed on 42-d.Results showed that LPS challenge had no significant effect on serum corticosterone and IL-1β level and growth performance（P0.05）.The percentage of abdominal fat,protein/fat ratio of pectoralis of birds in LPS were about 17.81% and 36.94% higher than those in CK,respectively（P0.05）,while pH value of pectoralis were about 2.23% lower than those in CK（P0.05）.In conclusion,immunological challenge had no effect on growth performance,but had significant negative effects on the carcass quality and meat quality of broiler chickens.