Carcass yield and characteristics of Karadi lambs as affected by dietary supplement of rumen undegradable nitrogen fed with Nigella sativa

The objective of this work was to investigate the effect of two levels of rumen undegradable nitrogen (7 and 10 g UDN/kg DM) fed with two levels of Nigella sativa (0 and 7.5 g NS/ kg DM) supplementation to rations of karadi lambs on carcass characteristics, using 2 x 2 factorial experiment. Sixteen individual Karadi male lambs were used (four lambs for each treatment). They were weighing approximately 34 kg live weight and 7 months old. The diets were formulated to be given a 40% NaOH-treated barley straw DM to 60% concentrates DM. At the end of feeding trial the lambs were slaughtered after over night with feeding draw. Differences in daily nutrients intake among treatments were not statistically significantly. The UDN and total N intake were followed the intended treatments composition (P < 0.01). Live weight gain was not significantly affected by levels of UDN and NS supplementation. Slaughter body weight, hot and cold carcass weights and killing out proportion were not significantly affected by both NS supplementation and levels of UDN. Moreover, no differences in leg cut tissue (lean, subcutaneous fat: intramuscular fat and bone) among treatments. The main wholesale cuts weights were not significantly different among treatments. The differences in fat-tail weights between the NS and UDN treatments were not statistically significant. Key words: Lambs, rumen undegredable nitrogen, Nigella sativa, carcass characteristic.