Composição química do feno Tifton 85 amonizado com ureia

Abstract

This study aimed evaluating changes in the Tifton 85 (Cynodon spp) hay chemical composition under different urea doses and treatment periods. The study was carried out at the Forage and Pastures Sector, Animal Nutrition and Pastures Department, Animal Science Institute in Universidade Federal Rural do Rio de Janeiro, Seropédica-RJ, Brazil between August and September 2013. Completely randomized design with a factorial arrangement of five (45% N) (0, 1, 2, 3 and 4% based on dry matter) commercial urea doses distributed in a split-plot at two periods (30 and 45 days) for the bags opening, with five replications each was employed. The ammoniated material was stored in (1 kg hay / bag) plastic bags, sealed and after opening, samples were collected for bromathological analysis. No dose effect, time and dose x time interaction for dry matter, ether extract, neutral detergent fiber, acid detergent fiber, hemicellulose, cellulose, lignin, acid detergent insoluble nitrogen, mineral matter, total carbohydrates, B2 fractions and carbohydrates fraction (P> 0.05) were reported. The variables crude protein, neutral detergent insoluble nitrogen and non-fibrous carbohydrates were influenced by urea doses. The ammoniation of Tifton 85 hay with urea at 1; 2; 3: 4% doses on dry matter might promote increases in crude protein and non-fibrous carbohydrates. However, cell wall constituents of the forage might not be altered, as well.