Características de carcaça na raça braford medidas por ultrassom em diferentes sistemas alimentares

Abstract

The pressure exerted by the various segments of society and industry on the productive sectors of animal protein for the increased food intake and increased product quality , leading makers , practitioners and researchers to pursue the development of efficient methods creation and selection of animals in order to minimize production costs and provide a more competitive level merchandising . Meet quantitative and qualitative characteristics of carcasses is crucial in meat industry , to improve the quality of the final product . The determination of these characteristics , so fast , noninvasive and accurate, can be obtained by ultrasonography . Thus, the aim of this study was to evaluate the effect of two systems and their diets Braford steers slaughtered at 24 months of age to a constant weight . 103 animals were used , with body weight (BW ) 454 ± 68.63 kg and 24 ± 2.04 months. The animals were divided into two different farming systems , animal feedlot and pasture . The feedlot steers were fed with forage: concentrate ratio 37:63 ( dry matter ) . The animals had free access to water . The time of feeding feedlot steers was 68 days and were slaughtered at an average weight of 455 kg and average daily gain of 1,691 g / day. The animals finished on pasture were managed under continuous grazing on natural pasture improved with deployment of species winter - spring . The average weight at slaughter of steers grazing was 454 kg , achieved in 125 grazing days and average daily gain of 1,176 g / day. The animals were weighed and evaluated by ultrasound 48 hours before slaughter . We analyzed the following characteristics :BW - weight ; fat thickness between the 12th and 13th rib; untrassound fat thickness between the 12th and 13th ribs on carcass ultrasound ; PP8US – gluteus medius muscle depht ; PCQ - hot carcass weight , WHR - hot dressing . Statistical analyzes were performed using SAS PROC ANOVA . The analysis of Pearson correlation coefficients via the SAS PROC CORR . We observed a faster termination of animals in feed lot compared to those measured at pasture, but most of the features did not differ statistically , only for hot carcass yield . This fact can be explained by the short period of confinement of animals and have a standardized slaughter weight reducing variability among them . Both treatments showed good levels of UFAT 3:43 and 3:56 for pasture and confinement mm respectively, but the treatment lasted 68 days on feedlot for the same values of grazing animals that were 125 days of treatment. There was a statistically significant difference between the animals WHR 50.07 and 51.95% respectively on pasture and confinement , results of other studies agree with these values relate to diet and highly energy can generate best hot carcass .