Effect Of Fermented Feed Of Probiotics â…  To Replace The Soybean Meal In Diets On The Rumen Metabolism And The Performance Of Dairy Cow

The study focused on evaluating the effects of different levels of probioticsΙto replace the soybean meal in diets on rumen fermentation, diet digestionand blood parameters of dairy cows. The purpose was to select the best ratio of probioticsΙto replace the soybean meal in diets. The effects of the best ratio on the performance of dairy cows were vertified. Some theoretical basis for the future research and practical application were provided.Four cows fitted permanent rumen fistula were chosen. This test used 4×4 Latin Square of design. While setting the control group, using different levels of probioticsΙto replace the soybean meal in diets, 20%, 40% and 60%, respectively. The treatments were basal diet (A), the probioticsΙto replace the Soybean Meal in diets by 20% (B), the probioticsΙto replace the Soybean Meal in diets by 40% (C), the probioticsΙto replace the soybean meal in diets by 60% (D). The test was divided into 4 phases. Each pre–trial period was 15 d and the formal period of 10 d, and then studied the effects of different levels of probioticsΙto replace the soybean meal in diets on the degradation rate of dietary nutrients, diet apparent digestibility, rumen fermentation and blood biochemical parameters. The results showed that:(1) The different levels of probioticsΙto replace the soybean meal in diets had no significant effect on rumen pH(p>0.05). the concentration of rumen NH3–N of C reduced than A and B, but the difference was not significant (p>0.05), the concentration of rumen NH3–N of C significantly reduced than D(p<0.05). The total volatile fatty acids, acetic acid, acetic acid/propionic acid of C was higher than the other treatment groups, but the difference was not significant (p>0.05). The acetic acid/propionic acid values were greater than 3, so the type of dietary fermentation was acetic acid fermentation.(2) The degradation rate by DM, CP, ADF and NDF of C was significantly higher than the other treatment groups (p<0.05), and the apparent digestibility by CP, ADF and NDF of C was significantly higher than the other treatment groups (p<0.05). The apparent digestibility by CP, ADF and NDF of B was higher than A and D, but he difference was not significant (p>0.05), and the apparent digestibility by DM, CP, ADF and NDF of D was not increased.(3) The different levels of probioticsΙto replace the soybean meal in diets increased the blood plasma glucose, plasma total protein, plasma total cholesterol, plasma triglycerides, serum aspartate aminotransferase and serum alanine aminotransferase concentration, and reduced the concentration of blood plasma urea nitrogen, but the difference was not significant (p>0.05).The Comprehensive results of analysis showed that C treatment group was the best replacement group. According to the test choose of the best alternative to the ratio: the optimal replacement ratio of soybean meal was 40%. Using the comparison methods and the trial period of 55 d, 30 healthy Holstein cows were selected. According to the weight, parity, lactation length and milk yield at the same or similar principle, divided into control and experimental groups, each group had 15. The results showed that:The average daily milk yield, milk fat and milk protein of experimental group was significantly higher than the control groups (p<0.05), respectively increased by 7.75%, 4.09% and 3.93%. The somatic cell count of experimental group was significantly lower than the control group (p<0.05), reduced by 12.28%. The Lactose and milk fat solids of experimental group and control group had no significantly difference (p>0.05).