The analysis of meat traits of Sussex cockerels and capons (S11) at different ages.

The aim of the study was to compare Sussex cockerels and capons as well as to estimate the influence of age on slaughter yield and meat quality. The tests were performed on cockerels and capons from strain S11 (Sussex). At 16, 18, and 20 wk of age, a dissection of the entire carcass was conducted. The breast and leg muscles were tested for physio-chemical traits, as well as chemical parameters. It was noted that, due to significant differences in BW of the eviscerated carcasses between wk 18 and 20 of slaughter, the best time to cease rearing S11 cockerels could be wk 20. However, for S11 capons, the optimal time for slaughter appeared to be wk 18 (no significant differences in BW and carcass weight or musculature between wk 18 and 20). The trait which did not differ between cockerels and capons slaughtered at different ages was slaughter yield. Fatness of the cockerels increased with age whilst the weight of capons' skin with subcutaneous fat was the same at wk 18 and 20 of evaluation. With increasing age, pH indicators of cockerels and capons' breast muscles were increasing; the water holding capacity of capons' breast muscles were also increasing. Both cockerels and capons showed darker color of breast muscle at wk 20 compared to wk 16 of evaluation. Redness of the breast muscle in the following periods of evaluation did not show significant differences, although with age, the yellowness of the cockerels and capons' breast muscle increased significantly. Among cockerels and capons, the water content in the breast and leg muscles were decreasing with age whilst the protein content was increasing. A significant growing tendency of the percentage of fat share in the breast and leg muscles with age was noted in the capon group. Conclusions for breeding practice are as follows: due to meat and quality traits, Sussex cockerels and capons can be used until wk 18 or 20 of life.