Study On The The Characteristics And Effects Of Microecological Preparation Yeasts On Rumen Fermentation Of Dairy Cattle

The feed added with compound microbial inoculum can increase the dry matter intake, milk yield, production performance, nutrient digestibility and prevent ruminal acidosis in daily cattle.The ability for producing active substance of8yeasts was comparatively analyzed by determining the content of live bacteria and the concentration of organic acids, amino acids and polypeptides after fermentation. The results showed that yeast SR12, XR4, SC18had more obvious advantages than any other strains; SR12had fragrant flavour in fermentation and highest content of live bacteria with6.77×109cfu/mL; XR4had higher content of protein, amino acids, organic acids than others, with100.1mg/dL,43.85mg/100mL and56.10×l0-2mg/mg, respectively; SC18had higher conte nt of polypeptide with10.98x10-2mg/mL. Bacillus Spp. A15had higher secretion of amylase than others with1.89U/mL(P<0.05).Effects of8Yeasts on the rumen fermentation were analyzed by measureing the pH value of rumen fluid, concentration of NH3-N, BCP and VFA. The results showed that SC18and XR4reduced the concentration of NH3-N and YN7, YJ2increased rumen BCP concentrations significantly (P<0.05). YL5and YD6increased the total content of VFA significantly (P<0.05). These results indicated that XR4, SC18had the promotion function for rumen fermentation.The results of feeding test showed that somatic cell number in milk had reduced compared to the control group’s by21.81%with an extremely significant difference (P <0.05), the milk yield increased by6.84%(P>0.05), the content of milk protein, lactose in test group shows little change with insignificant difference (P>0.05). It proved that compound microbial inoculum can increase the milk yield and decrease the number of somatic cells.