R. Bras. Zootec.. 24/Jul/2018;47:e20170191.
Performance and carcass characteristics of goats fed crude glycerin in the feedlot and during pre-slaughter lairage
This study evaluated the effects of crude glycerin (CG) supplied separately from the other dietary ingredients to goats during the feedlot and in the pre-slaughter lairage on the nutrient intake, performance, behavioral and physiological parameters, carcass characteristics, and meat quality. Twenty-eight uncastrated male goats from a cross between the Boer breed and mixed-breed goats were used in a completely randomized design in a 2 × 2 factorial scheme, consisting of the feedlot with or without CG inclusion in the diets (96.90 g kg-1 DM) and the pre-slaughter lairage, also with or without the ingredient. In the feedlot, goats fed CG had a lower intake of dry matter and nutrients. Crude glycerin intake reduced the weight gain and body weight of goats and increased feed conversion. Weights of carcass and cuts (leg, loin, ribs, and shoulder) were lower when the animals consumed CG in the feedlot. In pre-slaughter lairage, concentrations of cortisol were lower when the animals consumed CG. Characteristics of carcass and meat (pH, color, water holding capacity, cooking loss, and shear force) were not changed by the supply of CG during the pre-slaughter. When supplied during the feedlot period and separately from the other dietary ingredients, CG negatively affected the performance and carcass characteristics of goats without changing meat quality. In the pre-slaughter lairage, CG intake lowers the cortisol level and does not change the behavioral parameters or carcass and meat characteristics of goats.