Palma forrageira em dietas de novilhas leiteiras confinadas: desempenho e viabilidade econômica

Abstract

The objective of this work was to evaluate the influence of increasing levels of forage in the diet on performance of crossbred heifers 3/4 Holstein-Zebu and economic viability. Twenty four heifers with initial body weight of 163.00 ± 18 kg, distributed in a completely randomized design with four diets and six replications, were used. We used sorghum silage, concentrate and increasing levels of forage in the diet (0, 200, 400 and 600 g kg-1). Regarding the performance of heifers, there was no difference in height at withers, thoracic perimeter and feed conversion among diets. The average daily weight gain decreased with the concentration from 0.00 to 600.00 g kg-1 dietary palm. The final body weights ranged from a quadratic function of palm levels. Dry matter (%BW), neutral detergent fiber corrected for ash and protein (%BW) and crude protein intake decreased with the palm levels. Neutral detergent fiber corrected for ash and protein, non-fiber carbohydrates and total digestible nutrients intakes were quadratically influenced by forage palm levels. Dry matter and crude protein did not differ among diets. Total digestible nutrients decreased with the inclusion of forage palm. The inclusion forage palm up to 400 g kg-1 provided better performance. For economic viability, the internal rate of return shows that diet with 400 g kg-1 forage palm resulted most satisfactory and its was more viable for a producer and investor, with return rate of 3 15% per month.