过瘤胃氨基酸水平对关岭犊牛生长性能、营养物质表观消化率及氮代谢的影响

Effect of rumen amino acid levels on growth performance,nutrient apparent digestibility and nitrogen metabolism of Guanling calves

试验旨在探究过瘤胃赖氨酸(RP-Lys)和蛋氨酸(RP-Met)对91~180日龄贵州关岭犊牛生长性能、营养物质表观消化率、氮代谢的影响。选取36头贵州关岭犊牛,随机分为4组,每组9个重复,每个重复1头犊牛。对照组(A组)犊牛饲喂基础日粮,B组、C组、D组分别在每头犊牛的基础日粮中添加15 g/d RP-Lys、15 g/d RP-Met、15 g/d RP-Lys+15 g/d RP-Met。试验期90 d。结果显示,与对照组相比,试验组犊牛平均日增重升高,犊牛粪便中氮的排泄量降低,粗蛋白的表观消化率升高。研究表明,在每头关岭犊牛日粮中添加15 g/d RP-Lys+15 g/d RP-Met能够促进犊牛生长发育,提高饲料转化率,降低粪氮排泄量,对犊牛体况发育无明显影响。

The experiment explored the effect of rumen lysine(RP-Lys)and methionine(RP-Met)on the growth performance,nutrient apparent digestibility and nitrogen metabolism of Guizhou Guanling calves aged 91~180 days.A total of 36 Guizhou Guanling calves were selected and randomly divided into four groups,with nine replicates in each group and one calf in each replicate.The calves in control group were fed a basal diet(group A),while the group B,group C and group D were supplemented with 15 g/d RP-Lys,15 g/d RP-Met and 15 g/d RP-Lys+15 g/d RP-Met to the basal diet of each calf,respectively.The trial period was 90 days.The results showed that compared with the control group,the calves in the experimental group demonstrated an increase in average daily weight gain,a decrease in nitrogen excretion in calf feces,and an improvement in the apparent digestibility of crude protein.The study indicates that adding 15 g/d RP-Lys+15 g/d RP-Met to the diet can promote calves growth and development,increase feed conversion rate,and reduce fecal N excretion,and there was no significant effect on the calves physical development.