生理应激对肉仔鸡胴体品质及肌肉品质影响

Effect of physiological stress on carcass quality and meat quality of broiler chickens

为考察生理应激对肉仔鸡胴体品质及肌肉品质的影响,选用108只1周龄肉仔鸡均分为对照组和皮质酮组,分别饲喂基础日粮和在基础日粮中添加30mg/kg日粮的皮质酮。21日龄时,测定肉仔鸡血液皮质酮含量;42日龄时,测定胴体和肌肉品质。结果表明:皮质酮组肉仔鸡血液皮质酮含量显著高于对照组(P<0.05)。皮质酮组肉仔鸡胸肌率、腿肌率、胸肌纤维面积、胸肌滴水损失率及胸肌脂肪含量分别比对照组低25.74%、10.47%、14.75、24.08%和42.86%,均差异显著(P<0.05)。皮质酮组肉仔鸡腹脂率、腿肌pH及胸肌中蛋白脂肪比分别比对照组高34.75%、6.65%和58.57%,均差异显著(P<0.05)。2处理间胸肌pH及剪切力,腿肌滴水损失率及剪切力,胸肌蛋白含量均无显著差异(P>0.05)。结果提示,皮质酮应激显著降低肉仔鸡胸肌率、腿肌率、胸肌滴水损失率和胸肌中脂肪含量,显著提高了肉仔鸡的腹脂率、腿肌pH及胸肌中蛋白脂肪比。

The effect of stress mimicked by corticosterone administration on carcass quality and meat quality of broiler chickens was investigated in this study.One hundred and eight 7-d broiler chickens were equally divided into control group（CTRL）and experimental group（CORT）,and were fed basal diet or basal diet plus of CORT 30 mg /kg diet,respectively.At 21 days of age,sera corticosterone level of broiler chickens was determined.At 42 days of age,carcass quality and meat quality were assayed.The results showed that serum corticosterone level of broiler chicken in CORT were higher than those in CTRL.Percentage of pectoralis and thigh muscle,myofiber area,drip loss and fat content of pectoralis of broiler chickens in CORT were about 25.74%,10.47%,14.75%,24.08% and 42.86% lower than those in CTRL,respectively（P0.05）.Percentage of abdominal fat,pH of thigh muscle and ratio of protein/fat of pectoralis were about 34.75%,6.65% and 58.57% higher than those in CTRL,respectively（P0.05）.There were no significant differences of pH,shear force and protein content of pectoralis,drip loss and shear force of thigh muscle between the two groups（P0.05）.In conclusion,stress induced by CORT administration declined percentage of pectoralis and thigh muscle,drip loss and fat content of pectoralis,and increased the percentage of abdominal fat,pH of thigh muscle and ratio of protein/fat of broiler chickens.