| Scope and method of study. In 1994, an experiment was conducted to compare the effects of different forms of sodium and potassium and chloride versus sulfur in the dietary cation-anion balance equation (DCAB, calculated as meq ((Na + K) - (Cl + S))/kg diet DM) on acid-base status and mineral balance in sedentary horses. Six diets were fed in a Latin square design experiment with Dietary Cation-Anion Balance's of +0 (L:S), +53 (L:Cl), +405 (H:KC), +364 (H:KB), +360 (H:NaC) and +409 (H:NaB). Blood gasses and urine pH were measured to determine the acid-base status of the animal. The concentrations of the minerals Na, K, Cl, P, Mg, S and Ca were measured in serum, feed, fecal and urine samples to determine apparent daily mineral balance.;Findings and conclusions. The feeding of excess strong cations in relation to anions in the form of citrate or bicarbonate salts resulted in similar increases in urine and blood pH, blood bicarbonate, base excess, blood and base excess, extracellular fluid. The feeding of excess anions in relation to cations in the form of sulfur had similar, but not as pronounced, effects as that of chloride on acid-base status as evidenced by decreases in urine and blood pH and increases in urinary H$sp+$ excretion. Those horses consuming diet L:Cl had significantly lower serum cation-anion balance as compared to those consuming diet H:KB at 6 of the 7 post feeding intervals measured. No treatment effect was detected on daily fecal output or dry matter digestibilities. The excretion of Na, K and Cl was determined to be largely dependent upon intake. Those horses consuming diet L:Cl had lower daily Ca balances as compared to all other diets. |
