Consumo, digestibilidade e desempenho de novilhas leiteiras alimentadas com dietas contendo torta de dendê

Abstract

The objective was to evaluate the effects of inclusion of palm kernel cake in the diet on intake, digestibility and performance of dairy heifers. Sixteen dairy Holstein-Zebu crossbred heifers with average age of 13 months and average weight of 183.4±32.5 kg were distributed to four treatments in a completely randomized design with four levels of palm kernel cake (0, 11.9, 22.9 and 34.2% from total dry matter), each one with four replicates. The intake of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), non-fibrous carbohydrates (NFC), ether extract (EE) and total digestible nutrients (TDN), and the apparent digestibility of DM, CP, NDF, NFC and EE were evaluated. There was linear reduction in DM, CP, NDF, NFC, and TDN intake. The apparent digestibility of DM and NDF reduced with the inclusion of palm kernel cake in the diet, while the apparent digestibility of CP and NFC showed quadratic effect. The inclusion of palm kernel cake in the diets resulted in linear increase in the apparent digestibility of ether extract. Weight gain decreased linearly with the inclusion of palm kernel cake in the diet, with values of 1.06, 0.99, 0.89 and 0.54 kg/day for diets containing 0, 11.9, 22, 9 or 34.2% palm kernel cake, respectively. Feed conversion was not affected by the inclusion of levels of palm kernel cake. The inclusion of palm kernel cake in the diet reduces nutrient intake and performance of dairy heifers during growth, but when used in levels up to 24.6% of the total diet, it provides weight gain compatible with growth programs aiming calving at 24 months of age. © 2012 Sociedade Brasileira de Zootecnia.