Acidosis in Cattle

An Overview

Abstract

As with all feedstuffs consumed by ruminants, grains are subject to microbial fermentation in the rumino-reticulum part of the stomach complex. Ruminants evolved digesting forages. Therefore, digestion of grain by the ruminal ecosystem is a relatively foreign situation. Consumption of large, single meals and microbial fermentation not only favored energy and protein utilization of forages, but also allowed ruminants to survive from other predators. However, these feeding habits create problems when high grain diets are fed. The microbial fermentation of starches contained in grains can proceed too rapidly causing the rumen to become acidotic. The severity of the acidosis may range from mild to life threatening. Genetic selection of beef cattle over the last 50 years has done little to reduce the incidence of acidosis. Possibly, the selection of Holsteins for increased milk production may have indirectly selected for decreased acidosis by increasing saliva flow (bicarbonate buffer) and increasing rate of passage.

In many situations, the consequences of acidosis affect feedlot cattle and dairy cattle similarly. However, there are also unique feeding and management differences between these two industries. In general, I will discuss the two industries together. Where specific feeding and management differences occur, I will discuss these livestock industries separately.