Current state of breast meat quality in standard- yielding broiler strains

The purpose of this study was to evaluate and compare the state of breast meat quality in the 2 most used standard-yielding broiler chicken strains on today's market: Cobb 500 and Ross 308. To achieve this, chicks from both sexes of both strains (n = 108 per strain and sex) were placed in a randomized complete block design (4 groups x 4 replicates in 4 blocks) and fed a standard starter, grower, and finisher diet from 1 to 35 d. At 35 d, birds (n = 40/strain/sex) were processed and their yield and breast meat quality were evaluated. The strain-by-sex interaction was not significant for most analyzed traits. Birds from the Cobb 500 strain had higher body weight (P < 0.001), greater breast meat yield (P = 0.02), and lower leg meat yield (P < 0.001) than Ross 308 birds. They also exhibited higher wooden breast score (P = 0.04) and greater drip (P = 0.01) and cooking (P = 0.01) losses. An in vitro glycolysis model revealed that postmortem decline in the pH of the Pectoralis major muscle was influenced by the interaction between strain and age (P < 0.001). At 14 d, the initial pH was higher (P < 0.05) in Cobb 500, but at 33 d it was similar in both strains. At both ages and for both strains, the ultimate pH in this muscle was reached at 3 h postmortem. In conclusion, the choice of strain and sex combinations for broiler production requires a compromise between meat yield and quality.