Efeitos do tamanho de partícula da silagem de milho e da presença de vitaminas B e hidroximinerais na dieta sobre a digestibilidade e comportamento ingestivo de novilhas Nelore

Abstract

Brazilian feedlot diets have a high energy concentration and most use whole corn plant silage as the main source of fiber. The objective of this study was to determine the effect of the theoretical particle size (13 mm and 24 mm) of whole corn plant silage, associated or not with the supplementation of a vitamin B complex and hydroxyminerals on performance and ingestive behavior of Nellore heifers. in termination. Ninety-six Nellore heifers with initial average live weight of 248,33 ± 36,28 Kg were used in a completely randomized design, with a 2 x 2 factorial arrangement, with 2 particle sizes (13 mm and 24 mm) and with or without the inclusion of B vitamins and hydroxyminerals. The diets were formulated to provide a gain of 1.5 kg/day, with ad libitum supply twice daily. The animals were housed in 32 collective pens with 3 animals each, and each treatment had eight replications. The treatments were: SPIM 13 mm without the additive (13C), SPIM 13 mm with the additive included (13A), SPIM 24 mm without the additive (24C) and SPIM 24 mm with the additive included (24A). An observation of feeding behavior was carried out for 24 hours during confinement. The animals were weighed at the beginning and end of the experimental period, after a 16-hour solid fast. In the final management, blood was collected from the animals and ultrasound was performed to evaluate the animals' carcass. The results of this study were not influenced by the different particle sizes and by the supplementation or not of the additive with B vitamins and hydroxyminerals.