Quantitative comparisons of select cultured and uncultured microbial populations in the rumen of cattle fed different diets

作     者：Minseok Kim Zhongtang Yu 

作者机构：Department of Animal SciencesThe Ohio State University 

出 版 物：《Journal of Animal Science and Biotechnology》 (畜牧与生物技术杂志（英文版）)

年 卷 期：2012年第3卷第4期

页      面：193-198页

核心收录：

学科分类：090502[农学-动物营养与饲料科学] 0905[农学-畜牧学] 09[农学] 

基　　金：partially supported by an OARDC award(2010-007)to Z.Y 

主　　题：16S rRNA gene Real-time PCR Rumen Uncultured bacteria 

摘      要：Background： The number and diversity of uncultured ruminal bacterial and archaeal species revealed by 16S rRNA gene firs） sequences greatly exceeds that of cultured bacteria and archaea. However, the significance of uncultured microbes remains undetermined. The objective of this study was to assess the numeric importance of select uncultured bacteria and cultured bacteria and the impact of diets and microenvironments within cow rumen in a comparative manner. Results： Liquid and adherent fractions were obtained from the rumen of Jersey cattle fed hay alone and Holstein cattle fed hay plus grain. The populations of cultured and uncultured bacteria present in each fraction were quantified using specific real-time PCR assays. The population of total bacteria was similar between fractions or diets, while total archaea was numerically higher in the hay-fed Jersey cattle than in the hay-grain-fed Holstein cattle. The population of the genus Prevotello was about one log smaller than that of total bacteria. The populations of Fibrobocter succinogenes, Ruminococcus flovefociens, the genus Butyrivibrio, and R. albus was at least one log smaller than that of genus Prevotello. Four of the six uncultured bacteria quantified were as abundant as F. succinogenes, R. flovefociens and the genus Butyrivibrio. In addition, the populations of several uncultured bacteria were significantly higher in the adherent fractions than in the liquid fractions. These uncultured bacteria may be associated with fiber degradation. Conclusions： Some uncultured bacteria are as abundant as those of major cultured bacteria in the rumen. Uncultured bacteria may have important contribution to ruminal fermentation. Population dynamic studies of uncultured bacteria in a comparative manner can help reveal their ecological features and importance to rumen functions.