低蛋白精料补充料对泌乳期放牧牦牛瘤胃发酵参数、 血清免疫指标及泌乳激素的影响.

李世关; 张潇戈; 杨得玉; 冯宇哲; 张晓卫; 崔占鸿

The aim of the experiment was to study the effects of low protein concentrate supplementation with per rumen lysine and per rumen methionine on serum immunity indexes, lactation hormones and ru‐ men fermentation parameters of lactating grazing yaks. Twenty-four lactating grazing yaks in good condi‐ tion and similar body weight were selected as test animals and randomly divided into three groups with eight replicates in each group. The high protein group (HP group) was fed concentrate supplement with 16.66% crude protein level, the medium protein group (MP group) was fed concentrate supplement with 15.05% crude protein level and additional 0.23% per rumen lysine and 0.03% per rumen methio‐ nine, and the low protein group (LP group) was fed concentrate supplement with 13.57% crude protein level and additional 0.46% per rumen ly‐ sine and 0.07% per rumen methionine. The pretest period was 8 days and the formal test was conducted for 40 days. The results showed that, ① there were no significant differences (P>0.05) in growth performance indicators among the three lactation yak groups; ② there were no significant differences (P>0.05) in rumen fermentation parameters among the three lactation yak groups, and there was a tendency to increase the concentration of acetic and propi‐ onic acids (0.05≤P<0.10); ③ there was no significant difference in blood immunity indexes among the three groups of lactating yaks (P>0.05), and immunoglobulin G tended to increase (0.05≤P<0.10); ④ there was no significant difference (P>0.05) between the blood immunity indexes of lactating yaks in the three groups. In conclusion, it can be seen that reducing the crude protein level in the concentrate supplement of lactating yaks by 1.5%-3.0% and supplementing the corresponding per rumen amino ac‐ ids did not affect the rumen fermentation of lactating yaks, nor did it affect the immune indexes and the secretion of lactation hormones of lactating yaks.

IMMUNOGLOBULIN G; YAK; DIETARY supplements; CONCENTRATE feeds; LACTATION

Feed Industry, 2024, Vol 45, Issue 24, p78

1001-991X

Academic Journal

10.13302/j.cnki.fi.2024.24.012