Effect of the yolk ratio of hatching eggs and genotype and sex on some meat quality traits in broiler chickens

In this study computer tomography (CT) was used for the in vivo determination of yolk ratio in 7,000 hen eggs (originated from two markedly different genotypes), in order to examine the effect of egg yolk ratio and sex and genotype on some meat quality traits of the hatched chickens. Based on the CT images obtained, eggs with extremely low, average and extremely high yolk ratio were chosen for further investigation (n=350 in each group in both genotypes). These eggs were incubated thereafter and hatched birds were reared and then slaughtered at 11 weeks of age. During the meat quality analysis, the dry matter, crude protein, crude fat and crude ash content of both of the breast and leg muscles and the colour of the breast muscle were determined. Based on the results it was established that the yolk ratio of the eggs had no significant effect on the measured meat quality traits (P>0.05). Genotype affected the dry matter, crude protein and crude fat content of the breast muscle and the dry matter and crude fat content of the leg muscles significantly (P<0.05). Higher values were measured in that genotype, which was selected partly for weight gain. Sex had no significant effect on the composition of the meat (P>0.05) \u2013 except the crude protein content of the breast muscle \u2013 but it affected significantly the colour of the breast muscle. Females had significantly lower L* and higher b* values than the males (P<0.01)