Substituição do milho por gérmen integral de milho na dieta de ovinos em confinamento

Abstract

Corn replacement by whole corn germen on intake, digestibility, performance and carcass characteristics of feedlot ewes was evaluated. Forty Santa Inês strain ewes, with mean initial weight 17 kg, were put in individual feedlots for 70 days and provided with eating and drinking troughs. Feed provided and wastes were weighed for intake control. The digestibility trial was undertaken 40 days after the start of the performance test by employing LIPE® as external marker. The ewes were killed after the feedlot period and their weight and carcass yield registered. Experimental treatments comprised five levels of corn substitution by whole corn germen (0; 25; 50; 75 and 100%). Corn replacement by whole corn germen decreased linearly intake of dry matter (1.002 – 0.639 kg/day), crude protein (0.152 – 0.099 376 kg/day) and neutral detergent fiber (0.425 – 0.329 kg/day). A linear increase occurred in ether extract intake (CEE g/day). Coefficients of apparent digestibility of dry matter, organic matter, crude protein, fiber and neutral detergent and ether extract were linearly reduced by the replacement of corn by whole corn germen. Reduction also occurred in body weight at finish (29.61 – 25.77kg), weight of empty carcass (24.28 – 18.55 kg) and mean daily weight gain (0.170 – 0.119 g/day). Hot carcass weight, cold carcass weight, hot carcass yield, real yield, commercial yield and rib-eye area decreased linearly. However, food conversion, loss through chilling and cover fat were not affected by the substitution. Results show that the sub-product is not recommended due to linear decrease in intake, digestibility and performance caused by the inclusion of whole corn germen.