SARA (Subacute Ruminal Acidosis) its characterization and consequences in cattle: Review

Abstract

The presence of subacute ruminal acidosis (SARA) in cattle herds, especially in dairy producers, has a direct consequence on health, animal welfare, reduction in immune mediation and profitability of the sector. SARA can be characterized as a clinical condition resulting from ruminal fermentation. For high production animals, the diets are balanced with high levels of grains, rich in carbohydrates. Thus, the degradation of these carbohydrates in the rumen increases the levels of short-chain volatile fatty acids and lactic acid. This process leads to a reduction in ruminal pH, below 5.8 and, consequently, a generalized disturbance in this compartment. In addition to these rumen disturbances, SARA can reduce the apparent digestibility of nutrients in the intestinal compartment. Still, SARA can cause other changes in the rumen epithelium and reticulum and, as a consequence, abscesses in related organs such as intestines, liver, heart and lungs. Ultimately, these complex clinical injuries will lead to the appearance of laminitis.