Climate, methane and greenhouse gas emissions on agenda

One takeaway message from the recent World Congress on Genetics Applied to Livestock Production was that the missing "genetics pieces" are in development.

Held every four years and attended by more than 1500 scientists in-person and online, the World Congress is affectionally known as the Olympics of animal breeding and genetics.

It is a global snapshot of current research priorities.

Global investment in delivering the missing "genetics pieces" was apparent at the World Congress.

About one in 10 papers presented was about climate, methane and greenhouse gas emissions, or improving efficiency.

It is now clear there is big variation in individual animal methane production, and some of this variation is controlled by genetics.

For example, between 11 and 21 per cent of variation in methane emissions from Australian dairy cows is estimated to be due to genetics.

Using DNA-based (genomic) prediction to develop a methane breeding value will equip farmers and producers with the ability to identify animals with lower methane emissions shortly after birth.

This will support informed breeding and management decisions.

Unfortunately, this missing "Lego" piece is still in development.

Given the growing urgency for effective options, with emissions reduction targets looming, waiting is not an option. Interim solutions are needed.

Research undertaken through the DairyBio initiative has shown that genetic improvement of other traits, such as survival and feed efficiency, contribute to lower methane emissions in dairy cows.

Genetic improvement of milk production traits also leads to lower emissions intensity - or lower emissions per unit of milk produced.

This means we can make genetic progress to lower emissions intensity without a direct methane breeding value.

The Australian dairy industry's Balanced Performance Index already supports simultaneous genetic progress on production, health and efficiency traits.

After 10 years of breeding, this currently translates to about a 20 kilograms per cow per year reduction in emissions (measured in carbon dioxide equivalents).

By placing greater emphasis on the traits most strongly linked to methane emissions there is an opportunity to further reduce the emissions footprint of milk.

Several countries, including Australia and Ireland, are preparing to release new indices that will do just this.

In August, the Sustainability Index will be released to Australian dairy farmers through DataGene.

This index is expected to deliver a 6.3 per cent reduction in emissions intensity by 2050 in Holstein cows and a 7.3 per cent reduction in Jersey cows.

Although this contribution is modest, unlike investments in fertiliser or feed, the investments made in genetics permanently accumulate in the herd.

The earlier we focus on breeding to reduce the emissions footprint of milk, the greater the impact breeding can have.

A new index and (later) a methane breeding value are not the only Lego pieces genetics can offer.

At the World Congress, Ireland shared a plan to DNA-test (genotype) every single beef and dairy calf as part of its emissions reduction strategy.

Of course, these "genetic Lego pieces" are part of a much larger Lego set and will need to be used alongside other management practices to achieve a carbon neutral future.

In the race to achieve net zero emissions by 2050, doesn't every piece - whatever its size - count?