Estimating methane coefficients to predict the environmental impact of traits in the Australian dairy breeding program

The dairy industry has been scrutinized for the environmental impact associated with rearing and maintaining cattle production. There are 3 possible opportunities to reduce emissions through genetic selection: (1) a direct methane trait, (2) reduction in replacements, (3) an increase productivity. Our aim was estimate independent effects of traits Australian National Breeding Objective on gross production intensity (EI) herd average potential. Based similar published research, determined have effect include production, fertility, survival, health, feed efficiency. each trait produced per animal due improvement change EI (intensity value, IV) were estimated compared. herd, emitted cow year 4,297.86 kg carbon dioxide equivalents (CO2-eq). annual product output, expressed protein (protein-eq), 339.39 protein-eq 12.67 CO2-eq/kg protein-eq, respectively. Of included Objective, progress survival saved consistently shown result favorable impact. Conversely, had unfavorable when considering emissions, EI. Fertility minimal as its primarily accounted survival. Mastitis resistance only affected IV coefficients very limited extent. These may be used selection indexes apply emphasis based their impact, well applied by governments stakeholders track trends emissions. Although initiatives underway develop breeding values combining small data sets internationally, alternative options utilizing should further explored.