Rumen Microbiota and Nutrient Metabolism: A Review

Abstract

The rumen consists of a complex ecosystem where nutrients consumed by ruminants are digested by fermentation process, which is executed by diverse microorganisms such as bacteria, protozoa, fungi, bacteriophage and oscillospira. A symbiotic relationship is found among different groups of microorganisms due to the diverse nature of these microbial species and their adaptability and interactions. The ruminant provides necessary environment for the establishment of such microorganisms, while the microorganisms obtain energy from the host animal through microbial fermentation end products. The rumen microbial ecosystem fulfills several functions like fibrolytic, lipolytic and proteolytic functions and produce metabolites including volatile fatty acids (VFA), biohydrogenated lipids, microbial protein, methane etc. The purpose of this review is to contribute a better understanding of the fermentation processes that are taking place in the rumen and to provide information that can be applied for the development of new nutritional strategies to improve the digestion process for achieving maximum production.

Effects of Grape Pomace on Growth Performance, Nitrogen Metabolism, Antioxidants, and Microbial Diversity in Angus Bulls

“…Upon entering the rumen, dietary lipids transform processes such as lipolysis and fatty acid biohydrogenation (BH). A portion is hydrolyzed by microbial lipases, yielding nutrients such as glycerol for bacterial utilization [34]. The remaining lipids proceed through the rumen and are digested and absorbed in the small intestine.…”

Microbial Metagenomes and Host Transcriptomes Reveal the Dynamic Changes of Rumen Gene Expression, Microbial Colonization and Co-Regulation of Mineral Element Metabolism in Yaks from Birth to Adulthood

“…Newborn ruminants mainly consume liquid milk through the abomasum for energy supply, while the rumen is the main place for nutrient digestion and absorption in adult ruminants [7]. The rumen contains a variety of microorganisms that are responsible for converting low-quality forage into high-quality animal proteins that can be absorbed by the host through microbial fermentation [8,9]. Those microbes work together synergistically and contribute substantially to the nutrient utilization, metabolism, growth performance and health of the host [10,11].…”