The use of microbes to increase production performance in ruminants

Abstract

This article was prepared from available literatures on the use of microbes to increase production performance in ruminants. Microbes have been used for several purposes in which improving nutrient content especially crude protein and reducing fiber content in animals feed are primarily reviewed. Information about the microbes capable to improve crude protein content such as Saccharomyces cerevisiae, Rhizopus oryzae, Aspergillus niger, Lactobacillus delbruckii and Bacillus spp. are provided. The microbes utilizing proteins and changing them into peptides, amino acids, and ammonia, are also reviews. In addition, cellulase-producing fungal zoospore such as Trichoderma harzianum capable of reduce crude fiber by breaking down cellulose and amylase-producing fungal zoospore such as R. oryzae used for fiber decomposition are included in this article. Other groups of fungi producing fiber-degrading enzymes such as A. niger, A. oryzae, A. phoenicis and Penicilium sp. are also explained. The use of these microbes can improve ruminant fermentation thus improving the animal production. However, the microbe may yield other fermentation products such as volatile fatty acid (VFA) and ammonia nitrogen (NH₃-N). They also carry out microbial protein synthesis. Due to the properties mentioned above, microorganisms are commonly used in ruminant feed as a guideline for increasing the growth of microorganisms, nutrients digestibility, productivity of both milk and meat quality. However, other factors contributing to the success of using microbes in ruminant production including surrounding environment, quantity and type of feed, microbe’s species, proportion of roughage to concentrate, and suitability for the animals must be concerned.