摘要
试验采用1日龄AA肉仔鸡198只,随机分为6组,每组33只。6组核黄素添加量分别为0,3.6(1NRC),7.2(2NRC),14.4(4NRC),21.6(6NRC),28.8mg·kg-(18NRC),其中0添加组为对照组,后5组为试验组,试验期49d,试验选在夏季高温季节进行(7-8月份),试验期间鸡舍温度30￣38℃,湿度60%￣80%。测定核黄素水平对热应激条件下肉仔鸡生产性能的影响。结果表明:核黄素水平对28,49日龄肉仔鸡体重有显著影响(P<0.05),添加28.8mg·kg-1核黄素组与对照组相比显著增加了7￣49日龄的平均日增重(P<0.05),并能显著降低29￣49日龄的料重比(P<0.05);核黄素水平对热应激条件下肉仔鸡7,14日龄时的体重无显著影响,添加不同水平的核黄素对肉仔鸡死亡率无显著影响,核黄素水平对热应激条件下21日龄肉仔鸡呼吸率无显著影响;随着日龄的增加,添加3.6,28.8mg·kg-1核黄素组与7.2mg·kg-1组相比显著降低了28日龄肉仔鸡的呼吸率(P<0.05),添加21.6mg·kg-1核黄素组与7.2mg·kg-1组相比显著降低了35日龄肉仔鸡的呼吸率(P<0.05),添加14.4mg·kg-1核黄素组与对照组相比显著降低了21,28日龄肉仔鸡的肛温(P<0.05)。
A total of 198 Arbor Acres broiler at 1 day of age were randomly divided into 6 groups, 33 broilers in each group. The levels of riboflavin added to 6 groups were 0, 3.6（1NRC）, 7.2（2NRC）, 14.4（4NRC）, 21.6 （6NRC）, 28.8 mg·kg^-1（8NRC）, respectively. Experiment periods were 49 d. The broilers in cages were raised at 30-38 ℃, and humidity of 60%-80%. The results showed that the effects of dietary riboflavin on weight of broilers at 28, 49 days of ages were significant, 28.8 mg·kg^-1 riboflavin significantly increased the daily weight gain at 7-28 days of ages, and increased the transformation efficiency of feed at 29-49 days of ages（P〈0.05）; riboflavin had no significant effects on weight at 7, 14 days of ages, mortality and breathing rate at 21 days of ages; with age increasing, 3.6, 28.8 mg·kg^-1 riboflavin decreased breathing rate at 28 days of age, 21.6 mg·kg^-1 riboflavin decreased breathing rate at 35 days of age, 14.4 mg·kg^-1 riboflavin significantly decreased rectal temperature at 21,28 days of ages（P〈0.05）.
