This experiment was conduct at Ruminant Research Station/State Board for Agricultural Research/Ministry of Agriculture for the period from 01/ 02/ 2012 until 03/05/2012. The experiment lasted 93 days .Twenty crossbred growing male goats weighted 26.11 ± 1.91 kg and 7-8 month old were equally divided into five groups (4 animals/ treatment).The dietary treatments were as follows: T1:concentrat diet without ground dates stone ,T2:concentrate diet contain 30% ground dates stone and 0.80 % urea, T3: concentrate diet contain 30% ground dates stone and 1.20 % urea, T4: concentrate diet contain 30% ground dates stone and 5.80 % soybean meal, T5: concentrate diet contain 30% ground dates stone and 7.80 % soybean meal. Animals were fed concentrate at the level of 2.5% of body weight, alfalfa hay was given as ad libitum basis as the roughage.
Results showed that total and daily weight gain and feed conversion efficiency had higher values (P<0.05) in diet T5 than the other experimental groups. The in vivo crude protein digestibility was significantly (P<0.05) higher in T1 compared to other groups. The highest (P<0.05) value of nitrogen free extracts and crude fiber digestibility were recorded in groups T4 and T5. Total digestible nutrients (TDN) was significantly (P<0.05) higher in group T1. Moreover, nitrogen intake showed higher values (P<0.05) in groups T2 and T3. Fecal and urinary nitrogen and total nitrogen secreted was maximum in group T5. Digestible and retained nitrogen were highest (P<0.05) in T5.