Comportamento ingestivo de bovinos de corte em pastagem de inverno com diferentes níveis de suplementação energética

Abstract

Ingestive behavior in pastures is an alternative to improve management strategies, the use of energy supplementation in temperate pastures, allows increases in animal productivity and by area, by providing a greater supply of nutrients to animals. However, the ingestive behavior of the animals can be changed, depending on the type and level of supplement used, and the animal will adjust its behavior according to the conditions that occurred in the environment in which it is in order to reduce unfavorable effects to grazing conditions, being able to meet the nutritional requirements of maintenance and the rest being destined for production. Thus, the objective is to evaluate the changes in ingestive behavior in beef cattle in the winter pasture Wheat BRS Tarumaxi (Triticum aestivum L.) and rye (Lolium multiflorum Lam.) managed with different levels of energy supplementation. The research was carried out at the Ruminants Teaching and Research Center (NEPRu) at the Federal Technological University of Paraná - Campus Dois Vizinhos during the months of May to September 2024. The experimental design used was that of random blocks, with three repetitions of area (0.72 ha/picket). The supplement levels used were: 0.8% of live weight (PV); 0.4% PV and 0% PV. 27 Purunã cattle with an average initial weight of close to 300 kg were used. The grazing method used was continuous with a variable capacity rate. The evaluations of ingestive behavior were divided into two periods (August and September), for 12 hours (7:00 to 19:00) and on two consecutive days. The variables forage mass, instantaneous forage supply, animal load, leaf, straw and dead material, did not differ (P>0.05). The chemical composition of the pasture did not differ (P>0.05) between supplement levels. The grazing time was lower (P>0.05) in the treatment with a higher level of supplementation (8g/kg PV) in relation to the others. The idle time was higher (P>0.05) in the treatment with a higher level of supplementation compared to the animals not supplemented. Supplementation up to 4 g/kg PV does not change (P>0.05) the grazing and leisure time. The number of cheweds per cake was higher (P>0.05) in the treatment without supplementation compared to the animals that received supplement. The variable cakes per minute was lower (P> 0.05) in the treatment without supplementation when compared to the other treatments. The wheat pasture BRS tarumaxi (Triticum aestivum L.) and ryegar (Lolium multiflorum Lam.), with the supplementation of 8g/kg PV made it possible to reduce grazing time and increase leisure time, possible effect of lower MS content in treatment without supplement.