Obtaining Capons from Hybrid Autosexed Chickens and Assessment of Their Meat Colour

Abstract

We realised an experimental model for observing the effects of caponisation from autosexed chicken hybrids between red Rhode Island males with barred Plymouth Rock females, thereby the one-day old chicks obtained through artificial incubation presented distinctive morphological characteristics between their gender. Male autosexed chicken hybrids were grown in a traditional (extensive) husbandry system, thus is was observed a good development pattern through manifesting the heterosis phenomenon. At the age of fourteen weeks, before sexual maturity the cockerels have undergone caponisation. The unilateral gonadectomy method was performed using a human tonsillectomy instrument and, in some individuals, gonadectomy was perfomed by squeezing the testes with the fingers, to test if there is any difference between intervention and recovery time. The individuals had a 100% surviving rate. After gonadectomy the caponised and theintact group were raised in the same environment and feeding conditions and monitored for morphological and weight differences. At the age of thirty weeksthe cockerels from the two groups, nine chickens each, were slaughtered in order to assess the quantitative and qualitative differences of the carcass. Weight determination revealed a higher mean weight before slaughtering in the caponised cockereles than of the intact group (i.e. 3.3 kg vs. 3.0 kg) and after in carcass (i.e. 2.5 kg vs. 2.2 kg). Visual examination of the carcasses revealed that the skin is of a more intense yellow in the capons and upon section the drumstick muscles had a lighter colour than the drumstick muscles from the intact cockerels (i.e. light red vs. dark red). There is also a difference regarding consistency of the meat in the control group is much harder than of the capons.