Methane is the main source of greenhouse gas (GHG) from ruminants. The focus of this study was to measure methane production (MPR) in industry cattle. The ultimate aim was to develop estimated breeding values (EBVs) for methane traits for use in genetic improvement to reduce GHG in cattle. A total of 548 Australian Angus and 102 Australian Charolais Beef Information Nucleus herd steers which were undertaking a net feed intake test at the University of New England “Tullimba” research feedlot, near Armidale NSW, were measured for MPR using GreenFeed Emission Monitoring (GEM) units The units provide short term MPR measurement anytime an animal visits a unit. Two-thirds of the steers from each breed visited the GEM units; most of them more than 20 times within a period which ranged from 50 to 66 days. There were significant (P < 0.05) sire differences in MPR, MPR per unit feed intake, MPR per unit body weight and MPR per unit average daily gain in Angus cattle. The significant sire differences in the methane traits indicates the presence of genetic variation for methane traits when measured by GEM units.