Effects of Ractopamine Hydrochloride on Growth Performance and Carcass Characteristics in Wool and Hair Lambs

摘要

Abstract This study aimed at evaluating the effects of ractopamine hydrochloride (RAC) on growth performance and carcass characteristics of wool and hair lambs. For this purpose, 48 lambs averaging 31.3 kg body weight, of which twenty were wool (Ramboullet x Suffolk) and twenty eight were hair (Tabasco) lambs, and four levels of RAC (0, 10, 20, and 30 mg/kg diet, dry matter basis) were used. Wool lambs fed 20 and 30 mg RAC had higher (P longissimus area as compared to 0, 10 and 30 mg RAC. In hair lambs there were not effect of RAC on growth performance and carcass characteristics. It was concluded that addition of RAC to finishing diets offered the best growth performance and carcass traits in wool lambs as compared to hair lambs.