The objective ofthis trial was to evaluate the carcass physical composition and meat qualityof crossbred cull cows, from the second (G2- 3/4Charolais (C) Nellore (N) and3/4NC) and third (G3 5/8CN and 5/8NC) generations of Charolais - Nellorerotational crossbreeding, feedlot finished and slaughtered at 465, 507 and 566kg. At the beginning of the experiment, the average age, weight and body conditionwere, respectively, 8.5 years, 388.6 kg and 2.35 points. The diet, with 48:52roughage:concentrate ratio, contained 12.5% crude protein and 2.99 Mcal of digestibleenergy per kg of dry matter. Carcass bone (16.55, 15.84 and 12.72%) and musclepercentages (63.5, 60.05 and 60.69%) decreased, whereas fat percentage increased(19.85; 24.32; 28.08%, respectively) as slaughter weight increased. The weightgain of the carcass edible portion between the extreme slaughter weights was77.36 kg, being 37.32 kg of muscle (48.24%) and 40.04 kg of fat (51.76%). Meattenderness evaluated by shear force, was significantly improved in animals slaughterat higher weight (4.94, 4.89 and 3.89 kgf/cm3, respectively). Meatcolor of 5/8NC cows was darker (2.87 points) in relation to 5/8CN cows (4.0points). Meat of G3 animals was tender than G2 (4.16 vs 4.99 kgf/cm³).Higher juiciness was observed for 5/8NC meat than for 5/8CN (6.49 vs 4.16 points),as result of lower cooking loss of 5/8NC meat (17.61% vs 23.33%). Increasingcull cows slaughter weight is a method to increase rapidly beef meat production,inclusively improving their quality.
