Características da fermentação ruminal da dieta de ovinos recebendo blocos multinutricionais contendo própolis vermelha

Abstract

The objective of this study was to evaluate the production of methane (CH4) and short-chain fatty acids (SCFA) in the diet of sheep receiving multinutritional blocks (MB) containing red propolis (RP). Four male Santa Inês sheep, castrated, weighing an average of 55 kg and equipped with ruminal cannulas were used. The animals remained in an area of elephant grass, divided into 30 m2 paddocks, and received supplementation with or without RP. The supplementation and additive were provided to the animals in the form of MB, which had soybean meal as protein source and corn bran as energy source, in addition to urea, molasses, minerals and solidifying agent. The MBs treated with propolis received 2 ml of purified and concentrated RP extract, equivalent to 0.145 mg of isoflavonoids. SCFA, CH4 and N-NH3 productions were determined by the ex situ ruminal fermentation technique. The effect of the addition of RP to the multinutritional blocks on the production of CH4 and SCFA was analyzed by a randomized block design with the time of collection in the plots and the treatment in the subplots, with 4 replications. The inclusion of RP as a natural ionophore additive in the diet of sheep receiving MB did not lead to a lower production of CH4. There was no significant difference in the production of C2 and C4 between treatments. The addition of RP increased the molar proportion of propionate, reducing the acetate:propionate ratio, also contributing to the increase in the total concentration of SCFA. These results indicate a great possibility for RP to be used as a natural ruminal modifier, highlighting the need for further studies to evaluate the best dosage and economic viability of using multinutritional blocks with RP additives.