Abstract

PARTIDA DE LA PENA, José Armando; CASAYA RODRIGUEZ, Tania Alejandra  and  RUBIO LOZANO, María Salud. Effect of zilpaterol hydrochloride on the carcass characteristics of Katahdin lamb terminal crosses. Veterinaria México OA [online]. 2015, vol.2, n.2, pp.01-13. ISSN 2448-6760.

Zilpaterol hydrochloride (ZH) supplementation (0 vs. 0.15 mg/kg live weight) was evaluated based on the carcass characteristics of Katahdin x Charollais (32 KCh) and Katahdin x Dorper (28 KD) crosses. Lambs were fed a mixed ration with 14% crude protein (CP) and 2.9 Mcal EM/kg DM. Data were analyzed using a completely randomized 2 x 2 factorial design: 2 genotypes (KCh and KD) and 2 ZH levels (0 and 0.15 mg/kg live weight). No interaction was found between ZH and the genotypes. Zilpaterol hydrochloride increased dressing percentage from 52.1 ± 0.3 to 53.7 ± 0.4% (P < 0.001). Animals that received ZH supplementation increased (P < 0.001) the area of their Longissimus dorsi (Ld) by 18.5% and had 7.5% more muscle, 6.0% less bone and 22.4% less fat compared with control lambs (P < 0.05). The breed of the sire had no effect on any of the variables studied. Final pH, fat thickness, conformation and linear carcass measurements did not change with ZH supplementation.

Keywords : Lamb; Zilpaterol; Carcass quality; Crossbreeding; Katahdin; Charollais; Dorper.