The aim of this is study was to test the hypothesis that corn can be partially replaced by crude glycerin (at a level of 50%) without affecting performance, ingestive behavior, ruminal parameters, meat composition, and fatty acids profile on the meat of heifers. Sixty-four intact plus four rumen cannulated Angus × Nellore heifers (359.0 ± 12.15 kg BW) were used. The cannulated animals received the same diets as the intact ones to determine the ruminal N-NH3 concentration, pH, and chewing activity weekly. All heifers were maintained in Brachiaria brizantha pasture and supplemented with a concentrate containing corn, soybean meal, urea, premixed minerals, and glycerin partially replacing corn. A completely randomized experimental design was used, with two treatments (corn ground or glycerin + corn ground). The inclusion of crude glycerin (high fat) decreased nutrients intake and ruminal N-NH3 concentration in the rumen but increased lipid intake. Inclusion of glycerin had no effect (P > 0.05) on ruminal pH, daily gain, performance, time spent eating, rumination, idling, or water intake. The moisture, ash, and protein contents of meat were not affected (P > 0.05) by crude glycerin intake. Crude glycerin increased saturated fatty acids (C14:0, C16:0, and C18:0) and decreased unsaturated fatty acids (C18:2n6c and C20:1) in meat. Despite the reduction in nutrient intake, we recommend crude glycerin to replace corn in concentrate because glycerin did not impair the performance, meat composition, and ruminal pH. Therefore, crude glycerin is a by-product that can partially replace corn in diets efficiently.
Keywords: Beef cattle; By-product; Glycerol; Polyunsaturated fatty acid; Rumen.