Estimativa de consumo e digestibilidade em novilhas leiteiras, alimentadas com dietas contendo diferentes níveis de inclusão de glicerina bruta, e avaliaçao de indicadores

Abstract

The objective was to evaluate the intake and digestibility in heifers fed different inclusions of crude glycerin through internal indicators (Dry Matter indigestible - MSi, and indigestible neutral detergent fiber - iNDF) and external (Lignin Purified and enriched - LIPE®). AS diets were composed of 88% corn silage and 12% of corn meal and soybean meal, with the inclusion of 0 (control); 2.5; 5.0; 7.5 and 10% crude glycerin on dry matter, provided replacing corn. Five Holstein-Zebu crossbred heifers with average weight 602.4 kg in confinement were used in the experiment. Diets were fed twice a day and 10% of leftovers. The experimental design was a 5x5 Latin square with split plots. It was found that the inclusion of glycerin instead of corn meal, up to 10% did not affect dry matter intake and digestibility of the diet. In the evaluations of intake and apparent digestibility of dry matter (DM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), acid detergent fiber (ADF), crude energy (EB) and non-fiber carbohydrates (NFC) it was found that the LIPE® was similar to data obtained by the standard method (total collection) these assessments, unlike the internal indicators, MSi and iNDF, who underestimated or overestimated evaluations in compared to the total collection. Fecal production determined by LIPE® indicator was similar to total feces collection since the MSi and iNDF indicators overestimated this assessment.