甘露寡糖对泌乳早期奶牛瘤胃发酵及生产性能影响的研究

Effect of mannan-oligosaccharides on rumen fermentation and production performance of early dairy cows

试验旨在研究甘露寡糖(mannan-oligosaccharides MOS)对泌乳早期奶牛瘤胃发酵及生产性能的影响。选择4头泌乳天数为20 d,日产奶量30 kg左右,体重550 kg左右的经产(二胎)中国荷斯坦泌乳奶牛,随机分为两组,对照组饲喂基础日粮,试验组饲喂在基础日粮中添加60 g的试验日粮,采用2×2交叉试验设计,每期21 d。结果表明:添加甘露寡糖可以显著提高奶牛瘤胃中总的挥发酸和氨态氮的含量(P<0.05),其中瘤胃液中乙酸含量有极显著差异(P<0.01),丙酸、丁酸的含量无显著差异(P>0.05)。对奶样进行分析,添加甘露寡糖可以显著提高乳脂率(P<0.05),并且明显降低乳中体细胞数(P<0.05),产奶量、乳蛋白和乳中尿素氮浓度均无显著差异(P>0.05)。试验表明,在日粮中添加甘露寡糖有助于提高奶牛瘤胃乙酸发酵比例,提高奶牛乳脂率。

The purpose of this study was to investigate the effects of mannan-oligosaccharides（MOS） onrumen fermentation and production performance of actating dairy cows. 4 20-days-lactation hol- stein cows were randomly divided into 2 groups. The milk production of the test cow was 30 kg. The control group was fed with basal diet. The test group was fed with a test diet supplement- ed with 60 g in the basal diet. Using 2x2 crosstest design. Each period was 21 days. The results showed thai mannan-oligosaccharides can signifi- can@ improve the w^latile acid and ammonia nitrogen content of total cow rumen （P〈0.05）. There was a significant difference in the content of acetic acid in rumen fluid （P〈0.01）. There was no significant difference in lhe content of propionic acid and butyric acid（P〉0.05）. Analysis of milk samples, man- nan-oligosaccharides can significantly improve the milk fat rate （P〈0.05）. And signillcanlly reduced the number of somatic cells （P〈0.05）. There was no significant difference in milk yiehl, milk protein and milk urea nitrogen concentration（P〉0.05）. Experiments showed that mannan-oligosaecharide in the diets helped improving tureen fermentation of dailw cows and increasing the proportion of acetic acid and milk fat.