In this study, the physical-chemical characteristics and proximate composition of the meat of of two strains of broilers (Paraíso Pedrês and Máster gris plumé - Super Pesadão, utilized for semi-intensive rearing) and Cobb® strain, utilized in intensive rearing systems) were evaluated. Differences related to strain and sex (males and females) were studied. Cobb® broilers were slaughtered at 45 days and the other strains at 85 days. The following characteristics were evaluated in breast and thigh meat: moisture, protein, ether extract, ashes, color (CIEL*a*b*), final pH, cooking loss (CL) and shear force (SF). Bird strain and sex influenced breast color parameters, with Cobb® presenting higher yellowness (b*) and redness (a*) means, whereas females had higher b* values and males, a* values. Paraíso Pedrês had lower SF values. As to proximate composition, there was an interaction between strain and sex, with higher ether extract values in the meat of Super Pesadão males. Cobb® birds presented higher lightness (L*) and b* values, and there was no effect of sex on color parameters. Higher pH and SF values were found in the meat of Super Pesadão birds. There was an interaction between strain and sex for b* and SF values, with higher b* values obtained with Cobb® males, while differences between sex, with superiority for females in the Paraíso Pedrês strain and for males in the Cobb® strain were found. Increased values of SF for males were obtained for Super Pesadão strain. Both Paraíso Pedrês and Super Pesadão strains presented physicochemical and proximate composition characteristics similar to those of Cobb® strain in the cuts breast and thigh so that in a few parameters, no differences between the birds kept in this two rearing systems were found.
An experiment was carried out to evaluate carcass traits of male and female broilers of two genetic strains (Paraíso Pedrês and Pescoço Pelado), slaughtered at 65, 75, 85 and 95 days of age, and reared under a semi-extensive production system. The following parameters were evaluated: body weight at slaughter (BWs), carcass weight (CW), carcass yield (CY), parts yield, including breast, drumstick, thighs, back, neck, feet, wings, abdominal fat pad (AF), and giblets (gizzard, heart, liver). Paraíso Pedrês males presented higher BWs and CW. Paraíso Pedrês females had higher breast yield. Thighs and drumstick yields were higher in Pescoço Pelado males. Back yield was similar at 85 and 95 days of age, wing yield declined with age. AF yield was higher in Paraíso Pedrês and in females. GY was affected by sex and slaughter age. The results of this work lead to the conclusion that Paraíso Pedrês males reach higher live and carcass weights at 85 and 95 days of age, and that breast yield is higher in this strain. On the other hand, Pescoço Pelado males present higher drumstick and thighs yields. Therefore, the choice of genetic strain, sex and slaughter weight will determine carcasses with different parts yield.