Sistema de producción con bovinos de carne en la estación experimental la Cumaca III. Peso a 18 meses

beef cattle production system at la cumaca experimental station iii. weight at 18 months abstract in this third article of a series, the weight character, adjusted to 548 days of age, was evaluated in calves of a registered brahman herd from la cumaca ？alí benavides zapata？ experimental station, located in the state of yaracuy, venezuela. weights of 4525 calves at 548 days were analyzed using mixed models techniques (including an animal model) to evaluate the following effects: sex, year and month of birth, age of dam, sire and dam effects. the overall average weight was 315±1.3 kg. all the effects were statistically significant (p<0.01), except for the age of cow with p<0.05, with an estimated annual phenotipic trend of 1291 g, a direct genetic trend of 724 g, and a maternal one of 203 g. heritability indexes were 0.24 and 0.10 for direct and maternal effects, respectively. it was concluded that cows produce calves with less weighs at 18 months on first parturition (3 years old) and at ages over ten years.