瘤胃稳定性脂肪对产后奶牛奶产量、牛奶成份和外周血白细胞数量的影响

选择经产、胎次相同和产奶量相近的荷斯坦奶牛40头,配对分组设计分为对照组和试验组,每组20头。对照组全程饲喂基础日粮,试验组饲喂基础日粮 瘤胃稳定性脂肪。结果:瘤胃稳定性脂肪对奶牛采食量无显著影响(P>0.05);试验组牛产奶量显著升高(P<0.05),乳脂率呈上升趋势(P>0.05),但乳蛋白率未见显著变化(P>0.05);试验组奶牛外周血白细胞总数和淋巴细胞数轻度上升(P>0.05),牛奶SCC呈下降趋势(P>0.05)。结果表明,补充瘤胃稳定性脂肪可提高产奶量,对于改善机体免疫机能有一定的作用。

Effect of Rumen-undegraded Fat on Milk Yield,Milk Composition and Peripheral Leukocyte Number in Post-parturition Dairy Cows

Forty multiparous Holstein dairy cows with similar parity and milk yielding of the last year were allocated equally into a control and an experimental group according to matched-pair grouping design. Beginning at the day of parturition until 90 days after parturition, cows in the experimental group were fed basic diet supplemented with 400 g rumen-passed fat. It was found that rumen-passed fat did not alter dry matter intake (DIM)(P>0.05). However, it increased milk yielding(P<0.05). Milk fat percentage tended to be increased by supplemental fat, although the differences between the two groups were not pronounced(P>0.05). There were no differences in milk protein percentage between the two groups(P>0.05). Supplemental fat had minor effect on total number of peripheral leukocytes and the number of lymphocyte(P>0.05); however, it tended to reduce somatic cell counts (SCC) in milk (P>0.05). It was concluded that supplemental fat increased milk yielding, and improved immune function to a certain extent.