NZ Methane Research Shows Limits of Breeding Low-Emission Dairy Cows

The programme, initiated in 2021 and supported by CRV, set out to identify low-emitting bulls.

The hypothesis was that these bulls would pass the trait on to their daughters.

Because a relatively small number of bulls sire the next generation of cows, this approach offers a cost-effective and innovative way to introduce low methane emissions into the national herd.

Early Promise From Low-Emission Bulls

Early findings were encouraging, with lower methane emission traits identified in young bulls, and clear evidence these traits were passed on to their growing daughters.

However, the final phase of the research, which measured methane emissions in those daughters once they were lactating, found that this trait does not seem to be expressed.

Future Research to Shift Focus

Executive director of the Ag Emissions Centre, Naomi Parker says while the outcome is disappointing, the findings are still valuable, and the job now is to shape the direction for future research.

"Genetics still can have a meaningful role in reducing gross methane emissions. For beef and sheep, we are still confident in the approach, and we will be feeding the insights from this trial into work underway in these areas. For dairy we will consider taking a different approach that will likely focus on measuring lactating cows for methane production to generate a DNA-based selection criteria."