01923naa a2200301 a 450000100080000000500110000800800410001910000240006024501510008426000090023552010180024465000210126265000200128365000230130365000240132665000180135065000180136865000110138665000220139765000100141965300080142970000230143770000180146070000190147870000240149770000220152177300780154319631152013-07-31       2013    bl uuuu     u00u1 u    #d1 aPEDREIRA, M. dos S.  aMethane emissions and estimates of ruminal fermentation parameters in beef cattle fed different dietary concentrate levels.h[electronic resource]  c2013  aAbstract: Using sorghum silage, the effect of roughage/concentrate ratios was evaluated on nutrient intake, digestibility, ruminal parameters and methane production by beef cattle. Three treatments (0, 30 and 60% of concentrate in DM of the diet) were distributed in three Latin squares, with nine animals and three periods. Dry matter intake increased as the grain concentration in diet increased; pH showed opposite behavior. Methane emissions were lower for animals fed the diet exclusively with sorghum silage as compared with those fed 30% of concentrate, but was similar to that of animals receiving 60% of concentrate. Losses of ingested gross energy as methane were reduced by 33% when grain concentration was increased in the diet. Concentrations of propionic and butyric acids were greater in diets with grain concentrate; acetic acid concentration was not affected. Concentrate in diet increases available energy for the metabolism, measured by lower losses of ingested gross energy as ruminal methane.  aGreenhouse gases  aNutritive value  aRumen fermentation  aSulfur hexafluoride  aEfeito estufa  aGado de corte  aMetano  aNutrição animal  aSorgo  aSF61 aOLIVEIRA, S. G. de1 aPRIMAVESI, O.1 aLIMA, M. A. de1 aFRIGHETTO, R. T. S.1 aBERCHIELLI, T. T.  tRevista Brasileira de Zootecnia, Viçosagv. 42, n. 1 , p. 592-598, 2013.