ESTIMATING WATER-CONSUMPTION AND FACTORS AFFECTING INTAKE IN GRAZING CATTLE

Water consumption (WC) by 39.5 animal units (AU) of grazing cattle was studied at a central Alberta site in summer. Average WC AU-1 was esti mated at 48.9 L d-1. WC increased by 0.68 L AU-1 (P < 0.01) for each p ercentage decrease in relative humidity, increased by 0.81 L AU-1 (P < 0.02) for each degree Celsius increase in maximum daily temperature, and increased by 0.15 L AU-1 (P < 0.06) as cattle grew and the season progressed. Relative humidity is shown to be an important determinant of WC in grazing cattle.