Induced cryptorchidism in lambs: effects on growth rate, carcass and meat characteristics

Abstract

SUMMARYPushing the testes of lambs 1 to 2 weeks old into the body cavity and applying a rubber ring to cause atrophy of the empty scrotum, did not prevent most testes growing in a subcutaneous position. A modified technique used in a second experiment, which caused ablation of the tunica vaginalis as well as the scrotum, impeded more effectively the descent and growth of the testicles.In the two experiments growth rates of the induced cryptorchids were, respectively, 15·3% and 6·0% (non-significant) greater than those of castrated males, dressing percentages were about 2 units lower, and fat depth over the eye muscle of 13th rib chops was 2·6 compared with 2·9 mm (non-significant) and 1·9 compared with 4·1 mm. Chops from the cryptorchids had a visual appeal similar to those from castrated male and from female lambs; differences in flavour detected by taste panel had no significant effect on overall flavour acceptability.Tenderness did not differ significantly between sex groups, but age and Warner-Bratzler shear values were significantly and positively correlated as were ultimate pH of the meat and age at slaughter. Cryptorchidism induced by the modified technique probably permits the production of heavier carcasses with lower fat cover than on castrated males and avoids practical disadvantages that may be encountered in raising entire male lambs.