Glicerina bruta na dieta de caprinos em terminação

Abstract

ABSTRACT This study was conducted to evaluate the productive performance of crossbred Boer goats finished in feedlots, fed diets containing increasing levels of crude glycerin (0, 4, 8 and 12%) replacing corn bran in the concentrate portion of the diet. Two experiments were conducted. The first trial intended to determine the average daily gain (ADG), dry matter intake (DM) and nutrients (CP, NDF, EE ) and alimental behavior, which is evaluated for time spent with intake, rumination and leisure time. Twenty crossbred Boer goats with an average initial weight of 17.06 + 2.16 kg were used in a randomized complete block design with four treatments and five replications. The animals were housed in individual pens for a period of 65 days, 14 day for adaptation and 51 days for data collection. For the second experiment (digestibility trial) four castrated male goats were used, with an average weight of 22.45 + 3.06 kg, (with pattern similar to the animals used on the feedlot trial), in a Latin Square Design (4 treatments x 4 animals x 4 collection periods), to determine the digestibility of DM, CP, NDF and EE. The animals were housed in metabolic cages for a period of 40 days with four collection periods (seven days for adaptation and three for data collection). On the first trial, the addition of crude glycerin did not affect (P>0.05) the ADG between treatments, with mean values of 98.3 + 27g, as well as dry matter (591 + 96g) and other nutrients intake were not affected as well. The time spent on intake and chewing increased along with the levels of crude glycerin in diets, while leisure time, even without statistical difference, decreased (16%) compared to control treatment. There was no significant difference (P>0.05) of the treatments on the time spent ruminating with an average value of 365.6 + 73.4 minutes/day, and the digestibility of DM, CP and NDF were not affected as well. However there was a quadratic effect for the digestibility of EE. It is recommended to include in the content of 12% crude glycerin without damage to the productive performance, intake and digestibility of evaluated nutrients.