Effect of different levels of compound microbial preparation on feed quality and rumen degradation characteristics of corn straw.

The experiment aimed to investigate the effect of different levels of composite microbial preparation on the nutritional composition, fermentation quality and rumen degradation of corn straw silage. The experiment was divided into four groups. The blank control group (CK group) did not add any additive. The experimental groups added 0.01% (T1 group), 0.02% (T2 group) and 0.03% (T3 group) of composite microbial preparation to the corn straw, sealed closed light fermentation for 90 d. The nutritional composition, fermentation quality and rumen fermentation characteristics of each group were tested. The results showed that the sensory scores of corn straw silage in the experimental groups was higher than those in the CK group and there was no difference between the experimental groups. The composite microbial preparation had little effect on the nutritional composition of corn straw silage. The pH values of corn straw silage in all the groups was around 3.8. The composite microbial preparation did not affect the content of ammonia nitrogen, acetic acid and butyric acid in corn straw silage (P>0.05). Compared with the CK group, the lactate content of corn stalk silage in the T1 group, T2 group and T3 group was increased by 96.45%, 37.56% and 84.77% (P<0.05), and the total volatile fatty acid content was increased by 2.50%, 3.70% and 4.93% (P<0.05), respectively. Compared with the CK group, the rumen degradation rates of corn straw silage dry matter in the T1 group, T2 group and T3 group were increased by 7.54%, 9.32% and 10.32% (P<0.05), the rumen degradation rate of neutral detergent fiber were increased by 6.85%, 7.63% and 8.57% ( P<0.05), the rumen degradation rate of acid detergent fiber were increased by 19.51%, 13.78% and 15.37%, respectively (P<0.05). The experiment indicates that the addition of 0.02% composite microbial preparations has a good effect on improving the sensory, silage quality and promoting the degradation of rumen fibers of corn straw silage. [ABSTRACT FROM AUTHOR]