Crude glycerin in diets for wethers in feedlot: intake, digestibility, performance, carcass and meat traits

The aim was to evaluate the effects of crude glycerin levels (CG) (0, 2.65, 5.33, 8.06 and 10.84% in dry matter basis) on intake, digestibility, performance, carcass morphometric measurements and meat quality of sheep finished in feedlot. Twenty five crossbred Dorper x St. Ines wethers, with 24 +/- 2.0 kg average weight were housed in individual pens. The experimental design was completely randomized. Levels of CG in gross diet caused a decreasing linear effect (P<0.05) on dry matter, crude protein, neutral detergent fiber and non-fiber carbohydrates intake. Glycerin levels in the diet showed decreasing linear effect (P<0.05) on dry matter, crude protein, neutral detergent fiber and non-fibrous carbohydrates intake. Opposite result was observed for lipids intake. Digestibility coefficients of dry matter and non-fibrous carbohydrates decreased linearly (P<0.05) with glycerin levels, while the opposite was observed to ether extract digestibility coefficient (P<0.05). There were no effect (P>0.05) levels of glycerin on animal performance. For morphometric measurements of carcass and meat characteristics, no significant difference (P>0.05) levels of glycerin for hot carcass weight, chilled carcass weight, hot carcass yield, Chilled carcass yields, loss cooling, state of greasing, carcass length, leg length, depth of leg, chest depth, loin eye area, texture, marbling and color. However, the influence was observed (P<0.05) of increasing levels of crude glycerin on carcass conformation and carcass fat thickness. The use of crude glycerin reduced nutrient intake of the animals, however, did not influence the performance and carcass characteristics and is indicated its use in the diet of sheep.