Desempenho e rendimento de carcaça de novilhos mestiços leiteiros submetidos a dietas com diferentes níveis de concentrado

Abstract

The objective of this study was to investigate the influence of diets with increasing levels of concentrate (17.0, 34.0, 51.0, 68.0) on consumption, digestibility, performance, physical characteristics and commercialization of the carcass of 25 crossbred steers Of dairy breeds, with no defined blood level, in confinement. A completely randomized design was used. Data were submitted to analysis of variance and regression. Dry matter intake (CMS) increased linearly; The consumption of the other nutrients consumed the same behavior, except for the consumption of neutral detergent fiber and acid (NDF and FDA), which were influenced linearly and negatively. (P> 0.001), and positive for the apparent digestibility coefficients of dry matter (DM), NDF, crude protein (CP), ethereal extract (EE), organic matter (OM) and carbohydrates Non-fibrous (CNF). Final body weights (PCF) were not influenced. However, total and average daily weight gains added 1.16 kg and 9.90 g for each 1% increase in concentrate, respectively. The empty body weight (PCVZ), warm carcass weight (PCARQ) and cold carcass weight (PCARF) responded linearly to the increase in concentrate. The warm carcass yields (RCARQ); Cold carcass yield (RCARF); (GPCVZ) and carcass (GCAR) gains were also influenced positively and linearly, in the same way as carcass deposition efficiency (EDCAR) and carcass deposition rate (TXCAR). The increase in concentrate levels increased the consumption and digestibility of dry matter and other nutrients, improving food efficiency, performance and physical characteristics of the carcass, however, influencing linearly and negatively the economic return.