Meat Quality of Male Layer-Type Chickens Slaughtered at Different Ages

Abstract

An experiment with male layer-type chickens of the Lohmann Brown Classic breed was carried out at the Institute of Animal Science-Kostinbrod, Bulgaria, aiming to investigate the effect of age at slaughter on the meat quality. The birds were reared in a controlled microclimate, with an initial stocking density of 22 birds/m2. At five weeks of age, fragmentation of the stocking density was applied, decreasing the number to seven birds/m2. Chickens were slaughtered at five and nine weeks of age at an average live weight of 329 g and 1096 g, respectively. After slaughter, 10 chickens from each age group were subjected to analysis to determine the quality of breast and thigh meat. The results of the study showed that the age affected the meat quality parameters of the male layer-type chickens and its effect differed between the breast and thigh. The chickens slaughtered at nine weeks of age displayed a lower pH but darker meat color (p < 0.001) than those slaughtered at five weeks. Furthermore, the older birds showed a significant decrease in the intramuscular fat content in thigh meat (p < 0.01) and a tendency for diminishing in breast meat. This decrease corresponded to the lower percentage of monounsaturated fatty acids (MUFA) in the meat of the nine-week-old chickens (p < 0.01). On the other hand, the meat of the older chickens displayed a higher content (p < 0.01) of polyunsaturated fatty acids (PUFA), especially n-6, leading to a considerably higher n-6/n-3 ratio.