Filter Cellulose-Degrading Bacterial The Effect On Rumen Fermentation And Production Performance In Dairy Cows

The objective of this study was from Holstein cows in the rumen content to separate a bacterial strain with a higher decomposition on soybean straws, to detect this bacterial by microscopy and PCR molecular. And study the strain on the rumen fermentation and performance in dairy cows. The study included three experiments.Experiment1, the screen of cellulose decomposition bacteria, optimize enzyme production conditions and identification of the bacteria. Firstly, the study uesd soybean straw as roughage to feed4holstein cows which fitted with permanent rumen fistula lasted18d (feeding period15d, formal phase3d), soybean straw including haulm, pol, a small amount of soybean. To adopt in rumen content by negative pressure method. Then it was preliminarily screened using Congo red screening method, and then selected strain to degrade soybean straw by flask shaking fermentation method. Finally, determine the bacterial was what we want. The result shows that the optimum conditions for enzyme production as follows:training37degree60h, and inoculation quantity was10%, NH4NO3inoculation quantity was0.4%. In order to determine the bacteria, learned that target bacteria had a total of1509basic group, AT/CG=695/814, encoding503amino acids. It was a soybean straw disassembled bacterium, so we called it SD bacterial.Experiment2, the influence of SD on the ruminal fermentation of cows. Test using in vitro simulating rumen environment culture. According to the different levels of bacteria count divided it into:control (Ocfu/dL), treat1(0.75×109cfu/dL) and treat2(1.5×109cfu/dL) three groups. Each group set seven time points:2,4,8,12,24,36,48.The determination of indicators:gas production, rumen pH, NH3-N, volatile fatty acids, bacteria protein, neutral washing fiber, acid washing fiber. Results showed that the experimental group two. The indicators were better than the control group in the rumen, and the SD bacteria on rumen fermentation in vitro has a role in promoting.Experiment3, the effect of SD on the production performance of dairy cows. Check18Holstein cows. According to different bacteria preparation added in the diet it divided into:control (Ocfu/dL), treat1(0.75×1011cfu/dL) and treat2(1.5×1011cfu/dL). Each treatment had six Holstein cows.The experiment included feeding period(10d) and formal phase (40d). The result showed that after feeding SD bacteria in the diet for40d milk production from20.88kg/d to21.89kg/d and22.45kg/d, the4%fat corrected milk from19.47kg/d to20.73kg/d and21.50kg/d, they were significantly higher than control (P<0.05). Experimental group2milk protein rate of3.54%, and milk fat rate3.72%, and the control of the milk protein rate3.33%and butterfat rate3.59%. Treat2was significantly different compared with the control group (P<0.05). Lactose rate between each treatments was not significant different (P>0.05).In conclusion, screening SD bacteria and cellulose that had a efficient decomposition on soybean straw, and the optimum conditions of enzyme production is training37degree60h, and inoculation quantity was10%, NH4NO3inoculation quantity was0.4%.And idntificate it by PCR molecular identification and microscopic examination, so we called it SD bacterial. The bacteria in vitro rumen homeostasis has a certain role in promoting and it could improve the cow dairy quality and quantity of dairy cows.