This document discusses breeding cattle for lower greenhouse gas emissions in Australia. It found that there is natural variation in methane yield between bulls, with some being high and some being low methane yield. Selective breeding using low methane yield bulls could reduce cumulative enteric methane emissions from cattle by over 568,000 tons over 25 years. Adding a breeding value for low methane yield to selection indexes may help lower greenhouse gas emissions from cattle herds in a quantifiable and verifiable way.

1. BREEDING CATTLE FOR LOWER GREENHOUSE GAS EMISSIONS IN AN AUSTRALIAN CARBON TRADING ENVIRONMENT Robert Herd Industry & Investment NSW Beef Centre, Armidale, NSW This project is supported by funding from the Australian Government Department of Agriculture, Fisheries and Forestry as part of the Climate Change Research Program.

3. 95% of cattle emissions

4. Example: selection for feed efficiency brings a greenhouse gas benefit Reduction in methane emissions accompanies reduction in feed intake .

6. Methane yield (MY)

7. Found High and Low MY bulls

11. Early results: Averages for Methane Yield of Progeny (g methane/kg feed)

12. Might selective breeding change? Meat traits Cow traits

16. Add a BV for Low MY

18. BREEDING CATTLE FOR LOWER GREENHOUSE GAS EMISSIONS This project is supported by funding from the Australian Government Department of Agriculture, Fisheries and Forestry as part of the Climate Change Research Program.

21. Dr. John Goopy Also natural variation in sheep - heritable.