甜菜碱对慢性热应激肉鸡胸肌肌肉品质的影响

The effect of betaine on chest meat quality of broilers under chronic heat stress

为了研究慢性热应激对肉鸡胸肌肌肉品质的影响及甜菜碱的缓解作用,试验选择1日龄肉鸡60只,随机分为3组,预饲1周后,对照组按正常标准饲养,热应激组和甜菜碱组饲养温度为（32±1）℃,分别饮用自来水和0.2%的甜菜碱水溶液,于肉鸡28,35日龄时进行胸部肌肉品质测定。结果表明：28日龄时,与对照组比较,热应激组红度值、干物质含量极显著降低（P〈0.01）,黄度值显著升高（P〈0.05）,滴水损失、剪切力极显著升高（P〈0.01）;与热应激组比较,甜菜碱组红度值、滴水损失极显著升高（P〈0.01）。35日龄时,与对照组比较,热应激组剪切力极显著升高（P〈0.01）,红度值、干物质含量极显著降低（P〈0.01）;与热应激组比较,甜菜碱组红度值显著升高（P〈0.05）,干物质含量极显著升高（P〈0.01）,滴水损失与剪切力均极显著降低（P〈0.01）。说明饮水中添加0.2%甜菜碱可以显著提高热应激肉鸡胸肌肌肉品质。

In order to research the effect of chronic heat stress on chest meat quality of broilers,and relaxation effect of betaine during the process,60 1-day-old broilers were randomly divided into three groups in this experiment,and were fed for a week. Control group were given normal standard feeding,while heat-stress group and betaine-adding group lived at the the temperature of（ 32±1） ℃,and were given tap water and 0. 2% betaine contained water respectively. On 28 and 35 days post treatment,chest meat quality of broilers was determined. The results showed that,on 28 days,redness value and dry matter content in heat-stress group were very significantly lower than those in control group（ P0. 01）,while a significantly higher yellowness value（ P 0. 05）,very significantly higher drip loss and shear force（ P 0. 01）,in heat-stress group. Redness value and drip loss in betaine-adding group were very significantly increased compared with those in heat-stress group（ P 0. 01）; on 35 days,shear force in heat-stress group were very significantly higher compared with those in control group（ P 0. 01）,and a very significantly lower redness value and dry matter content（ P0. 01） in heat-stress group. Redness value in betaine-adding group was significantly increased compared with that in heat-stress group（ P 0. 05）,and a very significantly higher dry matter content（ P 0. 01）,very significantly lower drip loss and shear force（ P0. 01）,in betaine-adding group. The results suggested that 0. 2% betaine contained water could significantly improve chest meat quality of broilers under chronic heat stress.