A study conducted at Marj Al Kareem (The Scientific Agricultural Centre for Researches) in cooperation with Damascus University Faculty of Agriculture, The target group was Awassi sheep; about 323 ewes, 30 rams of the age "3-4 years", 424 lambs form the age 1 day to 5 months during the season 2002-2003. The animals have been put under the same nutritional and environmental conditions, and the same health care program.