Componentes não integrantes da carcaça de novilhos terminados em confinamento recebendo ureia protegida ou agrícola em substituição ao farelo de soja

Abstract

The effect of termination of steers in a feedlot using the total substitution of soybean meal by slow-release or agriculture urea on the non-carcass components was evaluated. Twenty-seven purebred and Charolais × Nellore castrated crossbred steers (mean age 20 months, mean initial weight 293 kg) were allocated to received concentrates containing slow degradation urea, soybean meal, or agricultural urea. The experimental design was in randomized blocks (breed predominance), with three treatments and nine replicates, with the animal being the experimental unit. Diets did not lead to significant differences in empty body weight (EBW). The similarity between treatments was also verified in relation to EBW/slaughter weight, with mean values of 0.87 for treatments containing urea and 0.88 for soybean meal treatment. The gastrointestinal contents, both in absolute weight and in relation to EBW, were similar between the rations evaluated, with mean values of 54.33 kg and 13.52%, respectively. Steers fed with slow-release urea had a 32.8% higher weight of omasum relative to 100 kg of EBW (P < 0.05) compared to the animals fed with soybean meal.

Conventional Feed-Grade or Slow-Release Coated Urea as Sources of Dietary Nitrogen for Fattening Lambs

“…In concordance with our study, Bourg et al [13] did not observe differences in the meat chemical composition when comparing conventional urea with SRU in finishing steers. Cardoso et al [64] reported a reduction in the marbling score when using SRU instead of feed-grade urea, but this effect was not supported by differences in the meat chemical composition.…”