体外产气法评价花生秧粉碎粒度对奶牛瘤胃发酵效果的影响

Effects of pulverized peanut vine size on rumen fermentation of dairy cows were evaluated by in vitro gas production method

本试验旨在利用体外产气法研究花生秧不同粉碎粒度对奶牛瘤胃发酵效果的影响。试验选用花生秧作为体外发酵底物,将其粉碎后分别取过18~20目(L组)、20~30目(M组)和30~40目(S组)的双层标准筛中间的花生秧样品,采集荷斯坦干奶牛(瘘管牛)瘤胃液,以不同粉碎粒度花生秧作为发酵底物进行体外产气法试验。试验设置3个试验组,每组3个重复。结果显示:M组的花生秧干物质(DM)降解率高于L组和S组6.79%、3.16%(P>0.05),粗蛋白质(CP)降解率高于L组和S组18.25%、25.73%(P>0.05),M组的挥发性脂肪酸(VFA)浓度高于L组和S组(P>0.05),氨态氮(NH3-N)浓度低于L组和S组20.00%、24.40%(P>0.05),体外发酵24 h的产气量(GP24)高于L组和S组6.73%、2.51%(P>0.05)。综上所述,花生秧的粉碎粒度会影响奶牛瘤胃发酵的效果,其粉碎后过20~30目的双层标准筛中间的花生秧粉料营养物质瘤胃发酵和瘤胃降解率效果更好,适宜将花生秧粉碎为该粒度作为日粮粗饲料来源,但其具体粉碎粒度仍需在实际生产中进一步探究验证。

This experiment was conducted to study the effects of different grinding size of peanut vine on rumen fermentation of dairy cows by in vitro gas production method.Test peanut seedling chosen as the in vitro fermentation substrates,respectively,after the crushing take the 18~20 mesh(L group),20~30 mesh(M group)and 30~40 mesh group(S group)of peanut seedling in the middle of the double standard screen samples,collected dry holstein cows gastric fistula(cow)tumor,with different granularity of peanut seedling as substrate for fermentation in vitro gas test.There were 3 experimental groups with 3 replicates in each group.The results showed that the dry matter(DM)degradation rate of peanut seedlings in M group was 6.79%and 3.16%higher than that in L group and S group(P>0.05),the degradation rate of crude protein(CP)of peanut seedlings in M group was 18.25%and 25.73%higher than that in L and S groups(P>0.05),the concentration of volatile fatty acids(VFA)in M group was higher than that in L group and S group(P>0.05),the concentration of NH3-N in M group was 20.00%and 24.40%lower than that in L group and S group(P>0.05),the 24 h in vitro fermentation gas production(GP24)in M group was 6.73%and 2.51%higher than that in L group and S group(P>0.05).To sum up,crushing particle size could affect the rumen fermentation of peanut seedling,the effect of the shattered after the middle of the 20~30 double standard screen peanut seedling powder rumen fermentation,nutrient and rumen degradation rate effect was better,suitable for peanut seedling shattering the granularity as diet roughage source,but its specific granularity of still need to further explore the validation in actual production.