高精料日粮下硫胺素对体外培养荷斯坦牛瘤胃微生物消化代谢的影响

本试验旨在揭示高精料日粮条件下硫胺素对体外培养荷斯坦牛瘤胃微生物消化代谢的影响。以2头安装永久性瘤胃瘘管的荷斯坦牛为试验动物，设置精粗比为6：4的底物，硫胺素的添加量设为0、60、120、180和240mg／kg5个水平，采用人工瘤胃体外发酵方法研究硫胺素对瘤胃微生物发酵的影响。试验结果表明．（1）高精料日粮条件下添加硫胺素可以提高培养液的pH值；（2）高精料日粮条件下NH3-N浓度随着硫胺素添加水平的提高而降低；（3）高精料日粮条件下硫胺素提高了细菌蛋白的产量而降低了原虫蛋白的产量。

Effects of Thiamin on the Rumen Microbial Fermentation Under the Condition of High Concentrate Diet in Vitro

The main objective of this trial was to study the effects of thiamine on the rumen microbe＇s fermentation in Vitro. Two Holstein cows equipped with rumen cannula were used for providing rumen fluid. And the in vitro culture were conducted using concentrate-to-forage ratio 6：4 as substrates, by adding thiamin at 0, 60, 120, 180 and 240mg/kg in culture medium respectively. The experimental results showed that： under the condition of high concentrate diet, pH value had an increasing tendency, NH3-N concentration reduced with the increasement of thiamin. Thiamin could ＇increase bacteria protein production and reduce protozoa protein to some extent.