Abstract
This study was conducted in Al-Rashidiya animal breeding station, using 6 ewes (2-6 yrs old) with average body weight of 42.7 kg with their single new born lambs, the ewes divided into 3 groups just after 4th week of birth. Ewes and their lambs. The ewes were paired randomly into three groups in cross over design with three periods each of 17 days , to investigate the effect of metabolizable protein: metabolizable energy in the rations (gm MP : ME MJ ). Three rations were used , the first consist mainly of barley, yellow corn, soybean meal and wheat bran(control R1 ).While the second ration R2 barley and wheat bran and third ration R3 also soybean meal were treated with acidic formaldehyde (9L/ton), the rations were iso calories and iso nitrogen but differ in MP : ME ratio which were 6.61 , 8.87 and 9.98 gm MP : MJ ME respectively . Results showed that feeding ewes on rations R2 and R3 significant (p
