Title: Influence of Sheep Breeds on Feed Intake, Growth Performance, Digestibility and Nitrogen Utilization
Abstract: Forty-five of intact three sheep breeds (Awassi, Harri, and Najdi) were used in this study (15 animals of each breed), with weight ranged from 23.40 to 25.87 kg. Five animals from each group at the end of growth trial were used for digestibility and nitrogen balance trials. The three groups of sheep had effect (p > 0.05) in the final live weight (FLW). Average daily feed intake (ADI), average daily gain (ADG) and feed conversion ratio (FCR) were significantly (p < 0.05) different among the three groups. For digestibility coefficients, the three breeds of sheep had no effect (p > 0.05) in dry matter (DM), organic matter (OM), crude protein (CP), crude fiber (CF), nitrogen free extract (NFE), neutral detergent fiber (NDF) and acid detergent fiber (ADF). In the similar approach, no significant differences were founds among three breeds of sheep in digestible organic matter, digestible of crude protein, total digestible nutrients and nitrogen retention. The current study concluded that the sheep breeds affected average daily feed intake, average daily gain and feed conversion ratio (FCR). Awassi breed showed the best of average daily gain and feed conversion ratio followed by Najdi then Harri breeds. The breed of sheep had no effect on digestibility coefficients and nitrogen retention.