Application of recombinant DNA to rumen microbes for the improvement of low quality feed utilization

Abstract

This paper paid particular interest to increasing the ruminal microbial biomass component from feeding low quality-based diets. This is characteristic of developing countries. Conventional approaches to supplementation includes the use of feed pretreatment of basal fibrous residues and feeding byproducts and various other feed additives. A more direct means of manipulating microbial synthesis compared to these may prove simpler and cheaper. This would involve ruminal coculture and strain improvement through genetic engineering. Genetic modifications may involve: increasing fibre cellulolysis, hemicellulolysis, pectinolysis and ligninolysis and introducing ‘storage’ proteins into rumen microbes and increasing ‘limiting’ amino acids in microbial metabolism. Plasmid-bearing genetic transfer systems applicable to rumen microbes and the production of such commercial inoculants is at a preliminary stage.