Effect of Different Levels of Commercial Saccharomyces cerevisiae with the Ration on Some Carcass Characteristics of Awassi Lambs

The aim of this study was to investigate the effect of adding different levels of commercial Saccharomyces cerevisiae (Sc) to the Awassi lambs ration on the meat and carcass characteristics. Sixteen local Awassi male lambs aged 6-6.5 months with initial weight of 36±0.34 kg were allocated and distributed into four treatments with four lambs each as follow: T1 (control), T2 (3 gm Sc/head/day), T3 (5 gm Sc/head/day), T4 (7 gm Sc/head/day). Wheat straw was provided ad libitum as a roughage diet while concentrate diet was provided for each treatment lambs by 2.5% of weekly live body weight for the whole study period ( seventy five days). At the end of the study, lambs were weighed then slaughtered. Results shows a significant superiority (P<0.05) of the T3 compared with T2 in the hot and cold carcass weight, also a significant superiority (P<0.05) of T 3 and 4 was detected in the dressing percentage comparing with control. Results revealed that the differences among treatments in the fore and hindquarter cuts were not significant. A significant decrease (P<0.05) was detected in the kidney and pelvic fat and fat tail percentages in the treated groups. The T4 showed a significant (P<0.05) backfat thickness among treatments. The significant differences (P<0.05) were found among treatments in ribeye area. Results showed a non-significant increase of lean and significant decrease (P<0.05) (except with T2) in the fat in treated groups. T3 shows a significant increase (P<0.05) in the protein and a significant decrease (P<0.05) in the fat among treatments, while T2 and 4 showed a significant superiority (P<0.05) in each of the moisture and ash respectively among treatments. The results of the current study confirmed the positive effect of adding Sc on the hot and cold carcass weight, dressing percentage and main carcass cuts.