RESPONSE TO WATER-DEPRIVATION BY YANKASA EWES UNDER DIFFERENT PHYSIOLOGICAL STATES

Thirty-six Yankasa ewes, used in a 50-day study, were 10 months old, non-pregnant and dry (12), 15 months old and 3-months pregnant (12), or 18 months old, lactating and non-pregnant (12). Three experimental watering interval treatments (1, 2, 3), daily (24-h interval), 48 h and 72 h, were conducted in the early, cool, dry season of September to November. Significant differences (P < 0.05) were observed in water intake for non-pregnant and dry, pregnant, and lactating ewes: 113 ml/kg0.73, 118 ml/kg0.73 and 188 ml/kg0.73 for 24 h; 91 ml/kg0.73, 96 ml/kg0.73 and 152 ml/kg0.73 for 48 h; and 77 ml/kg0.73, 89 ml/kg0.73 and 112 ml/kg0.73 for 72 h watering intervals, respectively. Feed intake of ewes dropped with increased water deprivation. Body weight decreased with prolonged watering intervals. Jaw movements during rumination were significantly reduced with increased watering intervals. Respiratory rates were less and rectal temperatures higher with longer watering intervals. © 1990.