Resumo

MACIAS CRUZ, Ulises et al. Growth and carcass characteristics of lambs finished with zilpaterol hydrochloride in grazing alfalfa. Rev. mex. de cienc. pecuarias [online]. 2016, vol.7, n.2, pp.243-252. ISSN 2448-6698.

The objective of the study was to evaluate the effect of zilpaterol hydrochloride (ZH) on the weight gain and carcass characteristics in lambs finished in alfalfa pasture and supplemented with concentrate in pen. A total of 24 Dorper x Pelibuey ram lambs initially weighting 25.0±0.24 kg were divided in two groups (n=12) and fed with 0 or 10 mg/ head/d of ZH for the last 30 d before slaughter. During the experimental period, all lambs were grazed in alfalfa during 8 h/d and supplemented with 450 g/d of concentrate. The ZH did not affect (P>0.05) the live weight. Daily and total weight gains were similar (P>0.05) between both groups. Carcass characteristics and wholesale cut yields were not affected (P>0.05) by ZH. In conclusion, growth and carcass characteristics were not improved by feeding zilpaterol (10 mg/head/d) in finished lambs on alfalfa grassland and supplemented with concentrate.

Palavras-chave : Hair sheep; β-adrenergic agonist; Zilpaterol; Grazing alfalfa.