Resilience of Lambs to Limited Water Availability without Compromising Their Production Performance.

Water scarcity is a common phenomenon in arid and semi-arid regions, which could have tremendous effects on livestock production. This study aimed to determine the level of water restriction that lambs fed on a pelleted diet can tolerate without compromising their production performance. A total of 24 male Najdi lambs were housed individually and randomly allocated into three equal groups, namely ad libitum water intake, 33% water-intake restriction, and 67% water-intake restriction. Dry-matter intake, feed conversion ratio, and average daily gain were decreased (p < 0.05) with the increasing level of water restriction. Water restriction had also reduced (p < 0.05) nutrient digestibility. The water-conserving ability of the water-restricted lambs was manifested by the production of concentrated and lower (p < 0.05) quantities of urine and feces. Meanwhile, serum osmolality and concentrations of albumin, total protein, urea-N, glucose, and non-esterified fatty acids were increased (p < 0.05) with the increasing levels of water restriction. It is surprising that lambs subjected to 67% water restriction retained more (p < 0.05) nitrogen relative to intake and had better (p < 0.05) efficiency of nitrogen utilization. It was strongly evident that lambs could tolerate water-intake restriction of up to 33% without compromising their production performance.