低磷日粮中添加植酸酶对蛋鸡肠道形态结构的影响

Effects of a low-available phosphorus diet supplemented with phytase on mucosal structure in jejunum of laying hens

试验旨在研究在低磷的玉米-豆粕型日粮中添加植酸酶对蛋鸡肠道形态结构的影响。选用18周龄体重、产蛋周龄相近的伊莎褐蛋鸡840羽,随机分成7组:正、负对照组及在负对照组基础上分别添加300、1000和10000U/kg的包衣状植酸酶、300U/kg的粉状及300U/kg的微丸状植酸酶(试验Ⅲ、Ⅳ、Ⅴ、Ⅵ和Ⅶ组)。结果表明:与负对照组相比,Ⅳ组的空肠绒毛高度得到了显著提高(P<0.05),Ⅲ、Ⅴ、Ⅵ和Ⅶ组与之相比无显著差异(P>0.05),但分别提高了16.49%、21.80%、15.73%以及17.29%;隐窝深度、绒毛高度/隐窝深度、黏膜厚度与之相比差异不显著(P>0.05)。各试验组间以及试验组与正对照组之间亦无显著差异(P>0.05)。因此,在低磷日粮中添加植酸酶对蛋鸡肠道结构具有一定的改善作用。

An experiment was conducted to evaluate the effects of a low-AP diet supplemented with phytase on the mucosal structure of small intestine in laying hens. A total of eight hundred and forty 18-week-old laying hens were randomly allocated into 7 groups. Group I, as the positive control, was fed with the basal diet, Group II, as the negative control, was fed with low-available phosphorus（AP） diet, while group Ⅲ, Ⅳ, and Ⅴ were fed with low-AP diet adding coated dosage-form phytase at three levels （300, 1 000, and 10 000 U/kg, respectively）, group Ⅵ and Ⅶ were supplemented with 300 U/kg phytase with powdery and granular dosage-form, respectively. The results indicated that： compared with the negative control, the jejunum villus height in group Ⅳwas increased significantly （P〈0.05）, while Ⅲ, Ⅴ, Ⅵ, and Ⅶ did not differ significantly （P〉0.05） with improved by 16.49%, 21.80%, 15.73%, and 17.29%, respectively. The crypt depth, villus height/crypt depth and mucosal thickness in trial groups did not differ significantly（P〉0.05） compared with negative control, there were also no differences among the positive control and the trial groups（P〉0.05）. It was concluded that low-AP diets supplemented with phytase could improve mucosal structure of small intestine in laying hens to some degree.