Quantitative aspects of nutrients recycling in the feces of bovines grazing a pasture of Brachiaria decumbens in the Zona da Mata region of Minas Gerais

The experiment was carried out at the experimental station of EMBRAPA/National Dairy Research, at Coronel Pacheco, in the Zona da Mata region of Minas Gerais, to evaluate the qualitative aspects of the nutrients recycling through the feces of grazing bovines. A 110 square meter plot was located in a previous established pasture of Brachiaria decumbens. There were significant differences on the nitrogen and magnesium concentrations of forage, for 10 weeks, apparently reflecting amounts in the forage. There were no variation of the other nutrients in the forage and feces. The average frequency defecation was of 9.84 defecations/animal per day and the average weight of the feces at each defecation was of 200.5 g dry matter. It was verified, by means of some data estimates, that the nutrients recycling in the feces, so 93.28% N, 76.68% P, 1.99% K, 72.93% Ca and 62.54% Mg, that was ingested by the animal returned to the pasture as feces, the same as 18.09% N, 35.46% P, 5.47% K, 30.26% Ca and 15.43% Mg, available as primary production, returned to the pasture through feces.