Carcass yields and breast meat composition of male and female Italian slow-growing chicken breeds

Carcass yields and chemical composition of two autochthonous Italian poultry breed, namely Bionda Piemontese (BP; n=64) and Bianca di Saluzzo (BS; n=64), were investigated considering breed, sex and their interaction during four consecutive slaughter age(5, 6, 7 and 8 months of age).Slaughter yields were evaluated and chemical composition was determined on the breast meat. Data were analyzed by one way ANOVA and Duncan test considering the breed, sex, and their interaction as the main effects. Males showed heavier final live weight (LW) (2626 g), carcass weight (CW) (1522 g) and thigh yield (39.15%), than females (1872 g, 1026 g and 32.40%). Females displayed greater breast yield (on average: 19.11% CW) during the different slaughter age (P<0.001), than males (on average: 17.03% CW). Breed showed a significant effect on carcass yield at the first (60.25vs 58.49% LW in BP and BS, respectively), third (59.56 vs 56.70% LW in BP and BS, respectively) and fourth slaughtering (57.85 vs 54.97% LW in BP and BS, respectively) (P<0.05). Carcass yield of BS females showed the highervalue at 5 and 6 months of age (59.03 and 57.58 % LW, respectively). Breast yield of the two breeds was influenced by the slaughter age and showed the lower value at 6 months of age (59.57 % CW in BP and 57.58% CW in BS). Breast moisture, protein, ether extract (EE) and ash contentswere not affected by breeds,except for ash at 6 months of age(1.18% vs 1.15 % in BP and BS, respectively)and EE at 8 months of age(0.43 % vs 0.28% in BP and BS, respectively). Sex influenced mainly moisture (on average 74.26% for males and 73.35% for females) and EE (on average 0.27% for males and 0.82% for females). Slaughter age influenced mainly moisture and EE of breast meat with the highest values at 5, 6and 7 months of age, respectively. Considering carcass parameters, slaughtering age at 7 and 8 months showed the best results in males and females of BP and males of BS.Five and six months resulted the best slaughter age in females of BS for carcass yield.