Slaughter yield, quality of meat from broiler chickens of different origin and age on diet with extruded or meal soybean

The study aimed to compare meat traits from different ages and origin chickens fed with extruded soybean (ES) instead of soybean meal (SBM). 150 male Ross 308 (R) and 150 male Cobb 500 (C) were used, with 2 replicates (75 birds each). The control groups (1) were fed with SM and experimental groups (2) with ES. After 35 and 42 days of rearing, birds were selected for slaughter (80 in total). The carcass and meat quality were analysed. A lower body and carcass weight was demonstrated in all variants in the experimental groups. The age of the birds affected all the slaughter traits of the chickens, with a benefit for day 42, except for the percentage of leg muscles and carcass remains. The origin of the birds influenced some features, especially fatness in C groups. The effect of the diet varied between age groups and origins, especially in the C group, where lower dressing percentage and muscle weight was shown, but the chemical composition was better for the ES diet. According to the effect of age and origin, feed with ES could be used due to carcass and meat quality results after 42 days, especially for Ross 308.