Effect of escape protein level on finishing performance of Awassi lambs

Two lamb finishing trials were conducted to evaluate escape protein (EP) level on finishing performance of fat tailed male and female Awassi lambs under neutral and high ambient temperatures. Twenty Awassi lambs (3–4 months old) in each trial were selected from the University flock and fed ad libitum concentrate feed and limited hay (100 g per day head) in individual fattening cages for 56 d. Experiment was arranged as a 2 × 2 × 2, factorial in which were concentrate feed EP level (low 3.4% versus high 5.0% DM basis), gender (male versus female), and temperature (neutral 18.7 ◦C versus high 30.4 ◦C). Two concentrate feeds were formulated with 16.0 and 15.9% crude protein on DM basis for low and high EP levels, respectively. Interactions between EP level, gender, and temperature were not observed (P > 0.05). Increasing EP level from 3.4 to 5.0% did not affect average daily gain (ADG), DM intake, and feed efficiency (P > 0.05). Male lambs had higher ADG, DM intake and better feed efficiency (P < 0.05). All the lambs had similar ADG, feed consumption, and feed efficiency values in both neutral and high ambient temperatures (P > 0.05). As a result, barley, cotton seed meal, and urea can meet the EP requirements of Awassi lambs without fish meal (FM) addition to the high crude protein (CP) containing lambs diet. © 2004 Elsevier B.V. All rights reserved