COMPORTAMENTO E CONSUMO DE NOVILHOS EM PASTEJO RECEBENDO 25-OH VITAMINA D3 NA RECRIA E TERMINAÇÃO

Abstract

ABSTRACT SILVEIRA, M. B. Behaviour and intake of grazing Nellore young bulls supplemented with 25-OH vitamin D3 in growing and finishing phases. 2022. Thesis (Master’s Degree) - Faculdade de Medicina Veterinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS.

Aimed to evaluate the use of nutritional additives with protein or protein-energy supplement to optimize the weight gain of animals kept on pasture. The use of concentrated protein and protein-energetic supplements with monensin and 25-OH vitamin D3 additition can generate satisfactory gains in beef cattle. During the rearing period there is a great physiological response in the body development of bovines, which must be explored with an adequate nutritional management. In turn, in the finishing period, which is a shorter phase and requires greater daily gains, the feed conversion becomes less efficient. Thus, a good nutritional strategy is essential for the success of production, with slaughter of better finished animals. The observations of the nutritional strategies can be observed by the responses in the intake and behavior of the animals. Thus, in order to evaluate the effects of supplementation associated with vitamin D3 on the growth and finishing of cattle on pasture, two experiments were conducted. In Experiment 1, one hundred and fifty animals with an average body weight (BW) of 300 ± 23 kg were used. Treatments consisted of protein supplement (Fosbovi® Proteico 30, DSM, Brazil), protein supplement with monensin (Fosbovi® Proteico 30M, DSM, Brazil) or protein-energetic supplement (Fosbovi® proteico-energico 25, DSM, Brazil); all supplements were evaluated with or without the addition of 25-OH Vit D3 (Hy-D®, DSM, Brazil), in a dose adjusted to a daily intake of 1 mg/animal. In Experiment 2, two hundred and forty animals with BW of 390 ± 16 were used. The treatments consisted of the same protein-energy supplement used in Experiment 1. Behavioral observations were made during the day, for twelve hours every five minutes. The following activities were evaluated: standing, lying down, walking, grazing, drinking and ingesting supplements. The animals that received protein-energy supplement had greater supplement intake (P<0.05) and water intake (P<0.05). Monensin and 25-OH Vit D3 reduced protein supplement intake when used separately (P<0.05). In experiment 2, 25-OH Vit D3 increased protein-energy supplement intake (P<0.05), but supplement intake in relation to BW did not differ (P>0.05). Overall, 25-OH Vit D3 in supplements for grazing animals does not have major effects on behavior.

Keywords: additive, monensin, protein-energetic supplementation, protein supplementation, supplement intake.