Effects of Giant Reed Leaves Replacing Alfalfa Hay on Rumen Fermentation Characteristics and Microbiota Structure of Dairy Cows in Vitro
The aim of this study was to investigate the effects of giant reed leaves replacing alfalfa hay on ru-men fermentation characteristics and microbiota structure of dairy cows in vitro.A single-factor experimental design was used to set up 5 groups,and 0(control group),25％,50％,75％and 100％giant reed leaves were used to replace alfalfa hay(dry matter basis),respectively.Each group underwent in vitro fermentation in batches for 3,6,9,12 and 24 h,with 3 replicates at each time point.Gas production parameters,nutrient degradation rates,fermentation parameters and microbiota structure were measured.The results showed as fol-lows:1)compared with the control group,after 24 h in vitro fermentation,there were no significant differ-ences in cumulative gas production,gas generation rate,gas production lag time,dry matter degradation rate and organic matter degradation rate in 75％group(P＞0.05),while the theoretical maximum gas production was significantly increased(P＜0.05);the ammonia nitrogen(NH3-N)content in 75％and 100％groups was significantly increased(P＜0.05),and the microbial protein(MCP)content was significantly decreased(P＜0.05);the contents of total volatile fatty acid(TVFA),acetic acid and butyric acid in 75％group were signif-icantly increased(P＜0.05),but there were no significant differences in propionic acid content and acetic acid to propionic acid ratio(P＞0.05).The pH in each group was within the normal range.2)After 24 h in vitro fermentation,there was no significant difference in microbial diversity among all groups(P＞0.05).At the phylum level,there were no significant differences in the relative abundance of each phylum in 75％group compared with control group(P＞0.05).At the genus level,there were also no significant differences in the relative abundance of each genus in 75％group compared with control group(P＞0.05).A total of 19 differen-tial species were identified by linear discriminant analysis effect size(LEfSe)analysis,of which 2,1,5,8 and 3 were in control group,25％group,50％group,75％group and 100％group,respectively.In conclu-sion,under the conditions of this experiment,the replacement of alfalfa hay with giant reed leaves can improve the rumen fermentation characteristics in vitro and increase the abundance of some degraded fiber bacteria,and the recommended replacement ratio is 75％.[Chinese Journal of Animal Nutrition,2024,36(11):7196-7211]
giant reed leavesalfalfa hayin vitro gas production methoddairy cowsrumen fermentation characteristicsmicrobiota structure
万方数据
维普
