Effect of Cation-Anion Difference on Measures of on Acid-Base Physiology andPerformance in Beef Cattle

摘要

In Florida, the dietary cation-anion balance (DCAD) characteristic of bahiagrass(Paspalum notatum) can be highly variable. This is a result of fluctuations in all fourelements making up the core DCAD equation, Na, K, Cl, and S. Bahiagrass receiving annualcontributions of S from ammonium sulfate fertilizer can accumulate high levels of S. In aprevious study (Arthington et al. 2002), bahiagrass fertilized with ammonium sulfate (60.0 lbS/acre) contained an average of 0.50% S (DM basis). Although cow acid-base physiologywas not measured, the high-S content of the ammonium sulfate fertilized pastures resulted ina decline in Cu accumulation in cows grazing these pastures. The ability of high-S contentbahiagrass to alter Cu status suggests additional important metabolic responses may beoccurring in cows.