Substituição do farelo de soja por uréia em dietas a base de capim buffel diferido para ovinos

Abstract

This study aimed to evaluate the performance of sheep using diets containing hay buffel grass with levels of urea replacing true protein sources, from the soybean meal in the feeding of lambs in confinement. The experiment was executed at the Fazenda Experimental Pendência Empresa de Pesquisa Agropecuária da Paraíba S.A (EMEPA). Thirty sheep without racial pattern set were used with an average of initial live weight of 17 ± 1.5 kg, which were distributed in a completely randomized experimental design, the initial body weight used as covariable, the experimental treatments consisting of five diets and six repetitions. The diets were composed by buffel grass hay and concentrated, the treatments represented by replacing the crude protein (CP) from true protein source (soybean meal) of food composed of PB from non-protein nitrogen source (urea). The diets were calculated to be isonitrogened and to supply the requirements of the animals for average daily gain of 200 g, according to the NRC (2007). The consumption of the animals were similar between animals fed with diet with 100% of PB from the soybean meal and other diets that contain urea, except the consumption of ether extract (EEC), which was higher for animals consuming 75% PB derived from urea. The hot carcass weight (HCW), cold carcass weight (CCW), hot carcass yield (HCY), carcass yield (CY), initial and final pH (pHi, pHi), morphometric measurements, weight of the commercial cuts were similar in animals fed with diet 100% of PB from the soybean meal and other diets that contained urea. The non-carcass components were similar in animals fed with 100% of PB from the soybean meal and other diets that contained urea, except the weights of empty carcass, gall bladder and perirenal fat that were influenced by the levels of urea in the diet. The replacement of crude protein from soybean meal for protein of urea provides similar performance in sheep consuming buffel grass hay.