Composição bromatológica e digestibilidade ruminal in vitro de concentrados contendo diferentes níveis de torta de girassol

Abstract

The aim of this study was the evaluation of the chemical bromatologic composition and dry matter in vitro digestibility (DMIVD) and crude protein in vitro digestibility (CPIVD) of concentrates containing differents levels of sunflower quacker (SQ) replacement soybean meal (SM) as source of protein. Three different treatments were utilized: Control = C (concentrate containing SM, corn and mineral mixture); T25 = treatment C plus SQ replacing 25% of the crude protein of the SM, and T50 = treatment C plus SQ replacing 50% of the crude protein of the SM, were studied according to a completely randomized design with five replications. The results showed significant differences in the composition of the concentrates concerning crude fiber (CF), neutral detergent fiber (NDF), ether extract (EE), total digestible nutrients (TDN), total carbohydrates (TC) and non-structural carbohydrates (NSC) contents, considering the bovine nutrition in specially dairy cattle. Values of acid detergent fiber (ADF) were very low. The averages obtained of CF, NDF and ADF were 4.95; 4.79 and 5.13%; 23.83; 23.88 and 27.03%; 5.08; 6.08 and 9.14% in order to C; T25 and T50, respectively. Values of dry matter (DM), crude protein (CP), mineral matter (MM), organic matter (OM), NDF, hemicelulose, nitrogen free extract (NFE), TDN, TC, and NFC averages did not differ between treatments (P>0.05). However, the T50 treatment produced higher CF, EE and ADF averages (P 0.05) with increase levels of SQ in the concentrates on the crude protein in vitro digestibility (CPDIV) coefficients. The averages of CPDIV coefficients were: 67.19; 63.16 and 71.62% respectively for the C; T25 and T50 treatments. Despite the variation in the digestibility coefficients the concentrates can be pottentially, up to 50% of inclusion of the SQ in the concentrate, used in bovines nutrition according to the cathegory requirement, disponi-bility and cost of the ingredients, specially SM and SQ. Key-words: Bovine, crude protein, Helianthus annuus L, ration.