1. Victorian Department of Primary Industries, Bundoora, VIC 3083, Australia
2. School of Land and Environment, University of Melbourne, Parkville, VIC 3010, Australia
3. CSIRO Animal, Food and Health Sciences, Queensland Bioscience Precinct, St. Lucia, QLD 4067, Australia
4. Animal Genetics and Breeding Unit, Armidale, NSW 2351, Australia
5. New South Wales Department of Primary Industries, Beef Industry Centre, Armidale, NSW 2351 Australia