Abstract
Forty-five Najdi ram lambs were equally and randomly allotted to five dietary groups with three replications per diet to evaluate the effect of feeding olive cake in complete diet on nutrient digestibility, growth performance and carcass characteristics. The diets were: a whole-mixed control diet (C) containing 12% wheat straw and four diets; namely O, ON, OU and OUE, where crude olive cake, 3% NaOH-treated olive cake, 5% urea-treated olive cake (U) and ensiled U, respectively were incorporated to replace the wheat straw of C diet. The results showed that the digestibility of DM, CP, EE and NFE and TDN were higher (p<0.05) in OUE diet as compared to the control diet; there were no changes (p>0.05) in the corresponding values between O, ON and OU diets. The nutrient digestibilities, body weight gain, feed efficiency and Longissimus area were significantly (p<0.05) lower in ON diet as compared to other experimental diets. Average daily DM intake and weight gain were higher (p<0.05) in lambs fed O, OU and OUE diets than those fed C diet. The moisture and protein contents in the soft tissue from ON treatment were lower (p<0.05) than those tissues from C, O, OU and OUE treatments. In conclusion, these results indicated that crude olive cake is a better substitute of wheat straw when fed to growing lambs. KCI Citation Count: 8