Effect of feeding straw-containing fermented feed on the composition and function of the rumen microbiota in heifers
This study aimed to investigate the effect of feeding straw-containing fermented feed on the composition and function of the rumen microbiota and metabolic physiology in heifers.A total of 36 healthy heifers aged 8-11 months were randomly divided into two groups,and fed 0 kg/d(control)and 4 kg/d of straw-containing fermented feed(the straw accounted for 16.0%of diet dry matter;treatment group)for eight weeks.The daily gain was measured every two weeks;the samples of rumen contents and coccygeal vein blood were collected at week eight to analyze the differences in phenotype and rumen microbiota between the two groups in heifers.The daily gain was significantly lower in the heifers in the straw-containing fermented feed group than in the control group(0.091 kg/d vs 1.080 kg/d,p=0.042).The total volatile fatty acid,serum β-hydroxybutyrate and triacylglycerol concentrations were significantly higher in the straw-containing fermented feed group than in the control group(p＜0.05),but with a lower glucose concentration(p＜0.05).The α diversity index of the rumen bacteria,such as the Sobs index and the Shannon index in the straw-containing fermented feed group were significantly higher than those in the control group(p＜0.05).The β diversity showed no significant differences(p＞0.05)between the two groups.The core species associated with the phenotype in the staw-containing fermented feed group was Anaeroplasma.In the microbial function,significant differences existed between the two groups mainly in carbohydrate metabolism and amino acid biosynthesis pathways.In summary,the straw-containing fermented feed promoted rumen fermentation and affected the blood lipid metabolism of heifers to some extents.This study made some breakthroughs in rumen microbial composition and functional differences as well as key microbiota excavation for the efficient utilization of straw feeds,which provides a practical basis for the effective utilization of non-conventional feeds in heifers.
strawfermented feedheiferrumen bacteriamicrobial function
NETL
NSTL
万方数据
