99 Why Should the Beef Industry be Concerned About gut Health?

Abstract

Abstract The gastrointestinal tract (GIT) uses a disproportionate amount of energy relative to its weight to facilitate digestion and movement of dig, nutrient absorption, and barrier function. Through these roles, the GIT acts as the first barrier for the immune system. As such, it is clear that understanding factors that affect these functions, particular absorptive and barrier function, can help improve nutrient utilization and limit immune activation. Cattle fed highly fermentable diets provide a unique opportunity to explore functions of the GIT and improve our understanding of the connection between digestive and metabolic disorders, and infectious disease. Consistent feed intake is a major challenge facing epithelia lining the GIT as feed-deprivation: induces behavioral stress that may alter epithelial cell function increasing risk for inflammation; induces rapid reductions in absorptive surface area; reduces rates of short-chain fatty acid absorption, and results in a transient increase in GIT permeability. Upon re-feeding, cattle previously experiencing off-feed events are at high risk for ruminal acidosis. Reasons for depressed feed intake are numerous and the off-feed event imposed by many diseases may provide a theorized linkage between respiratory disease, ruminal acidosis, and liver abscesses. Recent research has highlighted that increased GIT permeability may decrease gain and alter carcass composition supportive of inflammatory-mediated responses. In addition, there is growing evidence that highly fermentable diets may alter the regional permeability; however, future research is needed to confirm these findings.