Alternatives for calf and cattle fattening were validated, and capacities for beef production in grazing conditions were improved in the eastern part of Cuba. The reproductive behaviors of female Charolais, Creole and Zebu were evaluated for artificial insemination, along with the population data from the cattle fattening units. The herds from those breeds showed higher productivity, especially Charolais, which was higher than the other two. Only thirtysix percent of overall beef production is generated during the fattening stage; 43 % of weight achieved during fattening is produced in the calves, during reproduction. When fattening was started in the late rainy season, or early dry season, the final weights were significantly higher than the starting weights of animals that initiated fattening sometime else in the year. This can be linked to the relative contribution made by the concentrate supplement administered in the first months of fattening, around 30 % of the animal ingestion capacity, with effects on food conversion, and mitigating declines in availability and the quality of pasture in that period. If efficient exploitation capacities are created for these breeds, greater beef yields may be achieved, which will have a positive effect on cattle recovery in Cuba
