Abstract

This study was conducted on 2 stages using 18 Awassi lambs with average body weight (45kg). Animals were divided into 3 groups of six lambs each. During the first stage, the groups of lambs were individually fed on one of the three rations, which consisted mainly of barley, wheat bran and soybean meal, and contain three graded levels of crude protein 14, 16 and 18% in addition to urea and wheat straw. During the second stage lambs were fed on the same ration after treating barely and wheat bran with formaldehyde. Lambs were fed for 10 days as preperiod and then five days for fecal collection, rumen liquor and blood samples. The result indicated that there was no significant effects of formaldehyde treatment under different levels of protein on digestibility coefficient of Dry matter (DDM), Organic matter (DOM), crude protein (DCP), Nutrient Detergent Fiber (NDF) and Acid Detergent Fiber (ADF). While formaldehyde treatments significantly (P<0.05) affect the digestibility of ether extract (DEE) which were ranged between 51.61- 33.39% for untreated rations vs. 73.90-76.62% for formaldehyde treated rations. The results, also indicated that formaldehyde treatments significantly (P<0.01) affect the rumen liquor pH which was between (5.63- 5.82) in group fed untreated rations vs. (5.87- 6.14) in group fed treated rations. Ammonia concentration in rumen liquor was significantly decreased in group fed formaldehyde treated rations. While the treatments showed no significant effect on microbial protein synthesis in the rumen. Statistical analysis of blood samples showed that formalin treatments had no significant effect on glucose, urea, total protein and globulin serum concentration, but there was a significant effect on triglyceride and albumin concentration.