Short communication: Effect of breed on performance and carcass characteristics of Mexican hair sheep
To determine the effect of breed on growth performance and carcass characteristics in Mexican hair sheep, 48 lambs (average 38.9 ± 1.56 kg body weight, BW) were used in a completely randomized experimental design. The breed types assessed were 16 Pelibuey (PB), 16 Pelibuey x Katahdin (PB-KT) crossbred and 16 Pelibuey x Dorper (PB-DP) crossbred lambs. The lambs were fed a maize grain-based diet (88% concentrate and 12% forage) containing 155 g CP and 12.13 MJ ME/kg DM. The growth performance trial lasted 45 days. The average daily gain was significantly higher for the PB breed than for the PB-KT and PB-DP cross-breds. Feed intake in the PB and PB-KT was significantly higher than in the PB-DP. The feed conversion ratio was lower for the PB than for PB-KT and PB-DP lambs. Hot carcass dressing and leg perimeters were significantly lower for the PB than for the PB-DP lambs, and similar to that of the PB-KT lambs. The lowest dorsal fat values were measured in the PB breed, compared with both the PB-KT and PB-DP cross-breds. Mesenteric fat (as % of BW) in the PB was significantly higher than in PB-KT and PB-DP lambs. Empty rumen and small intestine weights (as % of BW) in the PB lambs were significantly higher than in the PB-DP lambs, but their large intestine was significantly smaller than in the other two breeds. It was concluded that the PB lambs have a better growth performance and carcass characteristics than the PB-DM lambs, but similar to that of the PB-KT lambs.
Keywords: Dressing percentage, longissimus dorsi, organ weights, lambs, Pelibuey, Katahdin, Dorper