Slaughter characterization of hair lambs from crosses with Colombian landraces

Objective. Evaluate the genetic effect of Dorper lambs crosses with Colombian landraces, fasting time and stunning in slaughter yields, blood glucose levels as a measure of stress and pH as carcass quality. Materials and methods. 60 Dorper lambs crosses with Colombian landraces feeding under grazing and semi-feedlot systems, 10 weeks old were used. 3 fasting times (6, 12 and 18 hours) and 2 stunning methods (electrical stunning and penetrating captive bolt) were applied, evaluating yield of carcasses by weighting, glucose antemortem and postmortem samples. Results. The results showed that the combined effect of fasting and breeding systems affects the carcass and by-products yields. At long fasting times, the concentration of blood glucose is increased, although the fasting time affects the ultimate pH. The stunning effect only occurs in the change of pH for 24 hours, with an effect of electrical stimulation by the electrical stunning. Animals Dorper crosses with Colombian landraces breeding in grazing system showed better carcass yields, but lower percentages of white and red viscera. Conclusions. The carcasses average yield is similar in pure Dorper breeds be viable and comparable this crossing.