Effects of Feeding Systems and Castration on the Growth Performance and some Carcass Traits in Lambs of Dhamari sheep- Yemen

نوع المستند : المقالة الأصلية

المؤلفون

1 epartment of Animal Production, Faculty of Agriculture and Veterinary Medicine, Thamar University, Dhamar, Yemen

2 Agriculture Research & Extension Authority, Dhamar, Yemen

3 Institute of Animal Nutrition, Department of Veterinary Medicine, Frei Universität Berlin, Berlin, Germany

المستخلص

A 3×2 experiment was conducted to investigate the effects of different feeding systems (FS) and castration on the growth performance and carcass traits in lambs of Dhamari sheep. 18 lambs were divided into 3 feeding systems with 6 lambs, 3 castrated and 3 uncastrated each. In the first FS, lambs were stall-fed and each lamb received daily 5% dried fodder sorghum, 8% alfalfa (fresh matter) and 1.5% concentrate. In second FS, lambs were grazed and fed 1.5% concentrate. In third FS, lambs were grazed and fed 2.5% dried sorghum fodder and 0.75% concentrate. The feed was offered on the basis of the average live body weight. This experiment was lasted for 120 days. Lambs were weighed fortnightly to measure growth performance. At the end of the experiment, four lambs from each FS (2 castrated and 2 intact) were randomly selected, weighed and slaughtered for carcass evaluation. Results indicated an increase of the total and daily body weight gains by lambs grazed and supplemented with 1.5% concentrate. The lambs grazed showed significantly lower feed intake and better feed conversion ratio (FCR) compared to lambs that did not graze. The grazed Lambs and getting 1.5% concentrate exhibited better weight of carcass and tail fat. The castration had a negative effect (P<0.05) on growth body, carcass weight, breast, liver, kidney and tail fat. In conclusion, the grazing lambs with an addition of 1.5% concentrate daily had the best effects on growth and slaughter traits whereas the castration showed negative effects on Dhamari lambs’ performance.