Effect of age and Waste of date packing factories on performance and carcass characteristic of fattening lambs

This experiment aimed to investigate the effect of fattening age and different levels of Waste of date packing factories on the performance and carcass characteristics of fattening lambs. 24 native lambs were fed for 90 days in a randomized complete block design with three levels of Waste of date packing factories (0, 10, and 20% of rations) and 2 fattening ages (4.5 months old, 23.03 ±0.92 kg or 6.5 months old, 31.44 ±3.61 kg). The results showed that the age of fattening had a significant effect on daily weight gain, dry matter intake, and feed conversion ratio (P<0.01). 6.5-month-old lambs had higher daily weight gain than 4.5-month-old lambs, but due to more dry matter intake, the feed conversion ratio of 4.5-month-old lambs was better. Different levels of Waste of date packing factories had no significant effect on daily weight gain, feed intake, feed conversion ratio, and carcass characteristics. 6.5-month-old lambs had higher carcass yields, and the percentage of internal organs weighed less than 4.5-month-old lambs (P<0.01). The interaction between fattening age and Waste of date packing factories had no significant effect on fattening age or carcass characteristics.  In general, 4.5-month-old lambs are fattened better than 6.5-month-old lambs due to their better feed conversion ratio. Also, Waste from date packing plants can be used up to 20% of the dry matter in the diet to feed fattening lambs.