高比例植物蛋白的代乳粉对断奶犊牛消化道酶活性的影响

Effects of High Vegetable Protein Content in Calf Milk Replaces Feed on the Digestive Enzyme of Weaning Calves

选取20头7日龄左右的荷斯坦奶公犊牛分配于试验组MR1、MR2、MR3和对照组CK,每组共5头。试验组MR1、MR2、MR3分别饲喂60%、70%、80%3种不同植物蛋白含量的代乳粉,对照组CK饲喂鲜奶,研究不同植物蛋白含量的代乳粉对断奶犊牛消化道主要消化酶活性的影响。犊牛8周龄时测定其小肠各段食糜中胰蛋白酶、糜蛋白酶和脂肪酶活性。结果表明,试验组MR1、MR2、MR3的小肠各段食糜中胰蛋白酶、糜蛋白酶活性均显著低于对照组CK(P<0.05),且试验组中MR1的活性最高,MR3的活性最低。试验组MR1、MR2、MR3的小肠各段食糜中脂肪酶活性均显著低于对照组CK(P<0.05),且试验组中MR1的活性极显著高于MR2、MR3(P<0.01),MR2的活性最低。由试验结果得出,断奶犊牛消化酶的活性随着代乳粉中植物蛋白含量的升高呈下降趋势,其中植物蛋白的种类也对断奶犊牛消化酶活性有很大的影响。

20 Holstein male calves were selected to determine the influence of the different plant protein contents of milk-replacer on the digestive enzyme of weaning calves between 7~60 days.Calves were divided in four groups： group MR1,MR2 and MR3 feeding milk-replacers containing 60%,70% and 80% of crude protein as vegetable protein respectively,group CK feeding whole milk as control group.At the age of 8 weeks,intestinal digesta was determined the activities of some important enzymes.Result： The activities of trypsin and chymotrypsin in group MR1,MR2,MR3 was lower than those of group CK（P〈0.05）,and in group MR1,MR2 and MR3,those of group MR1 was highest,those of group MR3 was lowest.The activities of lipase in group MR1,MR2,MR3 was lower than those of group CK（P〈0.05）,and those of group MR1 was significantly higher than other groups（P〈0.01）,and those of group MR2 was lowest.It is concluded that milk-replacer with increase of vegetable protein had the negative effects for pre-weaning calves,as for decreased the activities of trypsin,chymotrypsin and lipase.