The objective of this work was to evaluate the effect of different commercial strain (conformation versus conventional) on performance, carcass yield and parts, physical determinations (thickness, width and length of breast fillet) and breast meat quality (weight loss for cooking, shear force and pH) in broilers with 35, 42 and 49 days of age. Two thousand and four hundred day-old chicks were assigned to a randomized 5x2 factorial design, with five strains (conformation: A, B and C; and conventional D and E) and two sex, with four replicates of 60 birds each. The birds growth rate was different. Some strains showed higher growth rate among the conformation strains, as well as among the conventional ones. Strains also showed different performance for weight gain, feed intake and feed:gain ratio. Among the conformation strains, there was a strain that showed higher performance than the conventional ones, but the opposite was also verified. Carcass yield was affected at 35 days, and conformation strains presented the highest yield. Leg and leg meat yield were similar or better in the conventional strain, even so the highest breast and breast meat yield was observed for the conformation strain. Abdominal fat differed to 42 days but, only among onformation strain. Thickness, width and length of breast fillet were also different, and the conformation strain showed similar values to each other and superior than the conventional strain. There were no differences for meat quality. Sex of the birds affected the performance and carcass yield and parts, but did not affect the breast meat quality.
broilers; carcass yield; performance; quality meat; strain
