Findings from research funded by Meat & Livestock Australia (MLA) and the Australian Lot Feeders’ Association (ALFA) suggest that the equation currently used by Australia’s National Greenhouse Gas Inventory to estimate methane emissions from feedlot cattle may significantly overstate actual emissions. By Leatherbiz.

A study led by Professor Fran Cowley and Dr Amelia de Almeida from the University of New England assessed methane output using data from past research and a large-scale feeding trial. The study found that the widely used Moe and Tyrell (1979) equation overestimated emissions by an average factor of 2.4.

Researchers developed two new equations to improve accuracy, taking into account dietary components such as fat, fibre, and dry matter intake. Validation tests showed that the new equations significantly reduced the overestimation of methane output, from 115 g CH4 per day under the old model to just 6 g CH4 per day.

The findings could lead to a revision of Australia’s greenhouse gas reporting methods and provide a more precise basis for research into methane reduction strategies in feedlot cattle.