Systems analysis of beef production in the western high plains of Venezuela

Abstract

The Western High Plains of Venezuela were chosen for this study. Information used to describe the physical environment and genetic parameters required to simulate beef cattle production systems was obtained from the literature on the Western High Plains and similar areas. The current version of the Texas A&M University Cattle Production System Model was used to simulate the production in the area. The model was verified by comparison of the simulated levels of production with the results of the analyses of over 12,000 calf weights and 9,000 palpation records from three ranches located within the area. The levels of performance attained at these ranches were low as result of the combined effects of poor nutrition and high incidence of diseases. The simulated effects of different genotypes and management alternatives upon production efficiency, defined as liveweight of cattle sold per 100 kg of DM consumed by the entire herd, including slaughter animals and all replacement females, was examined. In the simulated environment, increase in cow potential mature size beyond 450 kg decreased simulated efficiency, because larger cattle were unable to consume adequate level of nutrients to meet their requirements, due to restricted availability of forage. A reduction in cattle size below 450 kg also decreased simulated efficiency, because a larger proportion of the nutrients consumed was utilized to fulfill maintenance requirements. Increased milk production potential over 9 kg decreased productivity, because cows, unable to meet their maintenance and milk production requirements from their forage intake, reduced their overall fertility. Reduction of milk production potential below the 9 kg level reduced calf's growth rate and fertility of the young cows which resulted in reduced efficiency..