The current systems of beef production must be competitive and oriented towards meat quality as a marketing concept. The objective of this investigation was to evaluate on grazing steers the effect of the genotype and nutritional supplementation finishing on growth, carcass composition, and cutability performance. The evaluation period was of 126 days during 2013. The research was conducted at the “La Vega farm” located in San Carlos, Alajuela, Costa Rica. In the investigation an analysis of production characteristics was performed, and the following were determined: daily weight gain, backfat, marbling, muscle depth, packing plant live weight, weight loss from farm to abbatoir, hot carcass weight, dressing %, muscle conformation, round circumference, carcass lenght, rib eye area, backfat, marbling, pH and temperature at 24 h and chill shrinkage. The genotypic component of cattle and the type of received supplementation affected the carcass traits. Brahman*Charolais (F1) crossed genotypes showed better performance than Brahman and / or Charolais, regarding characteristics such as muscle depth and yield in meat cuts, tenderloin, inside round and sirloin cap. The genotype and nutritional supplementation had no effect on total salable meat.

Keywords: beef cattle, animal carcasses, beef, meat quality.