02446nam a2200253 a 450000100080000000500110000800800410001910000180006024501250007826001580020330000150036152016140037665000200199065000140201065000210202465000090204565000110205465300210206570000240208670000200211070000160213070000220214670000240216810466052023-06-30       2003    bl uuuu     u00u1 u    #d1 aPRIMAVESI, O.  aLow fiber sugarcane to improve meat production with less methane emission in tropical dry season.h[electronic resource]  aIn: INTERNATIONAL METHANE & NITROUS OXIDE MITIGATION, 3., 2003, Beijing, China. Proceedings. Beijing: China Coal Information Institute: US ERG Inc.c2003  ap.185-189.  aOne of the main strategies to improve animal production and to reduce methane emissions in tropical animal production systems is to provide feed supplement to beef cattle in the dry season, when pasture forage production and forage quality are low. Without feed supplementation, beef cattle take three to six years to get the minimum accepted 450-kg slaughter weight. High-saccharose chopped sugarcane with 1% urea may be used to reduce weight losses, or plus grain-concentrate it may improve weight gain in the dry season, mainly with low NDF:saccharose ratio varieties. The main goal of this work was to improve knowledge on methane emission rates from varieties with extreme NDF:saccharose ratios. Experiments were performed with Holstein x Zebu crossbred dairy heifers, under controlled feeding, in a randomized block design, with 4 treatments: two sugarcane varieties, low- (cane1) and high-fiber (cane2), treated with either 1% urea (U), or substituting 40% of DM with a 18% crude protein concentrate (C), and three replications repeated twice. The experiment was carried out in late winter, in August 2001, the driest month. Methane emission was measured using the hexafluoride tracer method. Methane emission rates, per day and per kg LW were 113-166-122-140 g/d and 0.33-0.47-0.34-0.37 g/d/kg LW, respectively, for cane1U-cane1C-cane2Ucane2C. For pure sugarcane, values were 101 g/d and 0.27 g/d/kg LW. Results suggest that the use of lower NDF:saccharose ratio sugarcane variety plus concentrate will improve meat production with a lower methane emission per unit of product, in tropical dry season.  ameat production  asugarcane  aCana de açúcar  aGado  aMetano  aMethane emission1 aFRIGHETTO, R. T. S.1 aPEDREIRA, M. S.1 aLIMA, M. A.1 aBERCHIELLI, T. T.1 aRODRIGUES, A. de A.