Aspectos nutricionais e clínico-patológicos de bovinos de corte criados sob dois sistemas de confinamento e seu impacto econômico

Abstract

In the present study, data of major health problems in beef cattle raised under two different feedlot systems were collected and interpreted, as well as the costs for treatment. The traditional system that aims to produce animals for slaughter and the one that produces animals to be sold as future bulls were the two models of feedlot studied. The percentage of cattle confined for slaughter with health problems was considerably higher than the cattle raised in the system for future breeding. Pneumonia and digestive disorders were the main problems diagnosed in confinement for slaughter, and the cost for treatment was high accounting on average between 0.33 and 0.58 @/head or the equivalent of 7 to 12% of total @ gained during the period of confinement. The exaggerated growth and agglutination (parakeratosis) of ruminal papillae were the main macroscopic findings in the rumen of feedlot cattle raised for slaughter. Due to the high intake of grains, the ruminal and fecal pH was always lower, whilst ruminal osmolarity and blood lactate was always higher in cattle confined for slaughter. The time spent in confinement was higher, on average 4 days, for cattle that acquired any digestive problem. This, coupled with the fact that they have a smaller daily weight gain, can result in considerable economic losses. The daily weight gain was similar for cattle raised for slaughter (that ingested more than 85% of concentrated in their diet) and to those confined to be sold as bulls (which consumed about 50% of concentrated in their diet). The feedlot diet for slaughter always had a higher proportion of particles with size less than 8 mm and also had the highest osmolality. The feces of cattle confined for slaughter always had a higher proportion of particles larger than 4 mm in size