World Science and Research PublishingGlobal Journal of Animal Scientific Research2345-43773120141022Evaluation of Prospects Cattle Stallions of the Breed Simmental and Simbrah5764ENNelsonManzanares-MirandaUnivesidad Autónoma de Nuevo León, Centro de Investigación y Producción Agropecuaria. horacio.villalonmn@uanl.edu.mxHoracioVillalón-MendozaGustavoMoreno Degollado201409112014101420141010For Mexico, the units of agricultural and forestry production is the main land use in the country, covering 57.3% of the country. In this regard, the state of Nuevo Leon, has a surface density which amounts to little more than 5.5 million hectares, representing 86% of the state, with an inventory totaling 386.474 cattle heads, ranking 20, domestic production of beef. Additionally, in Nuevo León per capita consumption of that meat is 37 kg per year. The country's highest, above the national average of 21 kg. Watching this scene and Simmental breeds Simbrah an alternative to meet the needs of the state of meat production, based on the sustainability of natural resources, the nature of these breeds. Therefore, studies are needed to corroborate the ability to adapt to the ecological and economic conditions in the country of these two races promise for domestic producers, especially in northern Mexico. The aim of this study was to evaluate different production traits of economic importance of breeds Simmental and Simbrah under a suitable environment and uniform. Behavioral tests were used to evaluate stallion prospects. The study was performed in 4 months of observation, in Linares, Nuevo León, Mexico. It was making measurements monthly. The variables evaluated were: daily gain for the period (ADG), daily gain for age (GDE), weight adjusted to 365 days, loin eye area, intramuscular fat percentage, back fat, genetic markers (smooth and marbling), body size and scrotal circumference. The results showed that the Simmental breed behaved than the Simbrah for variables: daily weight gain and increase in final weight, no statistically significant differences compared to other variables.