Desempenho e qualidade de carne de cordeiros confinados recebendo óleo de castanha-do-Brasil em dietas com diferentes fontes de volumosos

Abstract

The study was carried out at Fazenda Conquista, Lavras-MG, to evaluate the effect of including Brazil nut oil (OCB), associated with different sources of roughage (corn silage (SM) or Tifton 85 hay (FT85), in the diet of lambs in confinement on: performance, chemical characteristics and fatty acid profile of meat, and economics of diets. 24 lambs were used, distributed in 4 experimental treatments ((6 animals per treatment): SMP - corn silage + standard concentrate; SM-OCB - corn silage + concentrate with OCB; FT85P - Tifton85 hay + standard concentrate; FT85-OCB - Tifton85 + hay concentrated with OCB. The animals that received SM presented higher values for: dry matter consumption (CMS), final weight before (PF) and after (PFJ) fasting, daily weight gain (GPD), subcutaneous fat thickness (EGS), weight of leg and percentage of collagen in the Longissimus lumborum (Ll) muscle compared to those who received FT85, regardless of the presence of OCB. The use of OCB, either with SM or FT85, provided lower values for: CMS; Final Weight; PFJ; GPD; EGS; rib eye area (AOL); weight of pallet and loin; proportions (% in FAME) of C20: 4n6 in Ll, and larger amounts (mg / g) of C22: 5 (DPA) in Ll. However, specifically in diets with FT85 with OCB, a higher percentage of fat in the muscle was observed, in addition to lower proportions (% FAME) of fatty acids C18: 2c9c12, C20: 3n6, C24: 1, and sum of omegas 6, and higher amounts (mg / g) of C18: 2c9t11 in Ll. The cost of feeding, considering feed conversion, was higher for diets that used MS, with or without OCB. Lambs finished with FT85-OCB diets showed lower performance and lower net revenue. The meat obtained from animals fed with OCB had better proportions of some fatty acids beneficial to health. However, when considering the way in which the final product is marketed and the values of the ingredients in the diets, the use of Brazil nut oil in finishing lambs can increase costs.