Studies on the water requirements of farm animals in South Africa. II. The relation between water consumption, food consumption and atmospheric temperature as studied on merino sheep’

Abstract

1. The consumption of lucerne hay and water by merino sheep has been recorded in two separate but identically concluded experiments under the following conditions: (i) Both food and water given ad lib. (ii) Water restricted to 2 litres, food ad lib. (iii) Food restricted to 0.6 Kg. water ad lib. 2. A highly significant positive correlation was found between the amounts of hay and water consumed when both were offered ad lib. 3. A highly significant positive correlation was also found between the amount of water consumed and the maximum atmospheric temperature for the day. This coefficient was enhanced by feeding a fixed amount of hay in the first experiment but not in the second. 4 . No direct correlation could be shown between the hay consumption and atmospheric temperature when water supply was unrestricted. In the first experiment a highly significant negative correlation was found between these two factors when a fixed amount of water was given, but this could not be confirmed in the second experiment. 5. Urine was collected from representative animals from each group. It was found that the animals on a restricted water supply maintained a low water to food ratio by passing small amounts of highly concentrated urine (urea up to 8.1 gm. per 100 c.c.). Marked variations were found between individual sheep receiving both hay and water ad lib. in respect of volume and concentration of urine.