Intake and productive performance of lambs of races Texel and Ideal, in feedlot diets containing different levels of soybean hulls

Abstract

This experiment, conducted in laboratory of sheep-raising of the Universidade Federal de Santa Maria, aimed to evaluate the effect of increasing levels of substitution of sorghum silage by soybean hulls on nutrient intake, weight gain and carcass traits lambs breeds Texel and Ideal, finished in feedlot. A total of 40 male lambs, not castrated, from simple birth, 20 and 20 of the breeds Texel and Ideal, all kept in individual pens. The treatments consisted of two breeds (Texel and Ideal) and four levels of substitution of sorghum silage by soybean hulls, where: 0, 33.5, 66.5 and 100% substitution. The Texel were slaughtered at 32.88 kg and Ideal at 27.51 kg, corresponding to 60% of body weight at maturity of their mothers. There was no interaction between races and levels of soybean hulls tested. The nutrient intake increased linearly, in various forms in which it was expressed with increasing inclusion of soybean hulls in the diets. The daily weight gain was quadratically influenced by the inclusion of soybean hulls in the diet. The maximum weight gain of lambs when feedlot is obtained by replacing sorghum silage by soybean hulls at 56.7%. Texel lambs finished in feedlot have a higher daily weight gain and better feed conversion when compared to the lambs breed Ideal.