Competition of three aggregated microbial species for four substrates in the rumen

Abstract

Rumen microorganisms play a vital role in the digestion of food and the supply of energy and amino acids to the host in the form of volatile fatty acids (VFA) and microbial protein. Because the products of rumen digestion are affected by microbial numbers and species composition, it is necessary to understand the population dynamics of different types of microorganisms. Mathematical models have been developed to represent the behaviour of rumen microbes, and these models have been included in whole-rumen models, however, several challenges still remain which include representing changes in microbe numbers and the interactions between microbial species or groups of species. We have developed a mathematical model based on a chemostat-type model of competition between functional representatives of microbes in the rumen and have studied the system numerically. Our objective was to develop and evaluate a mathematical model to examine the effect of changing the proportions of substrate and the effect of ammonia supplementation on the abundance of each species.