PSXV-17 Effects of increasing concentrations of soybean molasses on feed intake growth performance carcass and meat traits of feedlot lambs.

摘要

The objective of this study was to evaluate the effects of increasing concentrations of soybean molasses (SM) on feed intake, growth performance, carcass and meat traits of feedlot crossbred (Santa Ines × Dorper) lambs. Animals (n = 30, males, 60-d old, 20.4 ± 1.4 kg BW) were blocked by BW and randomly assigned to 30 individual pens and three experimental diets, containing 0 (M0), 10 (M10) or 20% (M20) SM, for 51 d. Corn silage was the roughage source (30%), and the concentrate was composed of corn grain, soybean hulls, soybean meal, urea, minerals, and soybean molasses. Daily feed intake and average daily gain were obtained recording feed delivery and orts, dividing by days on feed. When reached 35 kg BW, animals were harvested, and carcass and meat traits were evaluated. The data were analysed using MIXED procedure of SAS. The DM intake was linearly increased with the addition of SM (P = 0.004). However, no effects were observed on NDF, nor CP intakes. Treatments containing SM did not affect ADG (average = 0.293 kg), but the feed efficiency was linearly decreased (P = 0.05). The HCW, CCW and its dressing percentages (HCWD, CCWD) were not affected (averages = 16.6 kg, 16.0 kg, 47.0%, and 45.6%). Carcass’ temperature after 45 min. of slaughter tended to be quadratically affected (P = 0.07) with greater temperatures for M10. Carcass’ pH after 24 h had a linear effect with lower values for M20 (P = 0.02). Meat colour at 45 min. or 24 h after slaughter was not changed by SM addition (averages = 28.3, 12.1, 2.6, 34.2, 14.6, 5.4, respectively for L45, a45, b45, L24, a24, b24). The use of up to 20% SM in crossbred lambs’ diets increase DMI, without affecting significantly ADG and carcass and meat traits.