Effects of acid drinking water on nutrient utilization, water balance, and growth of goats under hot-humid tropical environment

Abstract

Water available for livestock in the tropical lowland region is generally high in acidity. This study determined the effects of the acid water on nutrient intake, water balance, and the growth of goats in the tropical environment. A total of nine Kacang goats were stratified based on body weight (BW) and assigned to three treatment groups which were offered drinking water at varying pH levels, namely 6.9, 5.2, and 3.8. All goats were offered ad libitum Asystasia gangetica hay and dried cassava chips at 1% of BW (dry matter (DM) basis) following a crossover design with three treatments tested in three periods. At the 5.2 pH level, drinking water intake (DWI) tended to be lower (P = 0.09) while total DM intake (%BW) was decreased (P < 0.05). Ruminal pH was significantly difference (P < 0.01); 6.98, 6.94, and 6.58 at the 6.9, 5.2, and 3.8 pH levels, respectively. Metabolizable energy and daily gain tended to be higher at the 6.9 and 3.8 pH levels compared to those at the 5.2 level (P = 0.08). There were no significant adverse effects of acid water on nutrient intake, utilization, and growth of Kacang goats. Moreover, the increase in temperature-humidity index was followed by the elevated DWI (P < 0.01) at 6.9 pH level, but no such significant relationship was found at other pH levels that indicated a better capability of thermoregulation response under heat stress exposure.