434 Strategies for improving the efficiency of rumen function

Abstract Ruminants are unique amongst livestock, having the ability to convert low cost and low-quality feedstuffs that cannot be consumed by humans, or non-ruminant animals, into high quality protein. Unfortunately, the low digestibility of these feeds also promotes reduced intake and performance, which limits their inclusion in ruminant diets. Variation in the ability of cattle to digest feed has also been considered one of the main factors affecting feed efficiency. In an extensive grazing system, greater feed intake and digestibility of forages are directly related to the performance of cattle fed. Development of technologies to enhance feed intake and digestibility of forage-based diets within the rumen is essential to increase their utilization in ruminant diets. Data will be presented from past, and current, efforts to understand inter-animal variability in feed digestibility, the linkages between the rumen microbiome and feed digestion efficiency, and to develop enzymes, and chemical pretreatment technologies that will enhance the digestion of lignocellulose in the rumen.