<b>Effect of dietary cation-anion balance, on acid-basic status and mineral metabolism of lactating dairy Holstein cows in hot weather</b> - DOI: 10.4025/actascianimsci.v26i1.1955

Abstract

The objective was to evaluate the response of lactating dairy cows to dietary Na, K, and Cl while holding cation-anion balance constant. Nine lactating Holstein cows, blocked according to age and previous milk yiel, wen assigned randomly to replicated 3x3 Latin esquares with experimental period of 3 week. Diets contained corn silage and concentrate ration in a 50:50 rate (DM basis) and were formulated to provide + 32 mEq of (Na + K) - Cl/100g diet DM via one of three variations: 1) control diet plus 1.57% of KCl in DM basis, 2) control diet plus 1.22% of NaCl in DM basis, 3) control diet. Samples of blood and of urine were collected four hours after feeding of the morning, in the last day of each experimental period for analysis of mineral Ca, P, Mg, Na, K, Cl and of Creatinin, and of the gasometria of the blood. The blood and urine pH did not suffer effect of the treatments. Any effect in the acid-basic balance and in the metabolism of the minerals in the blood and in the urine it was observed, showing that the animals did not answer to the supply of a balance dietary cation-anion of +32 mEq/100g of DM in the diet.