20 ways dairy producers can tackle net zero

Expert view: Marco Winters, head of animal genetics, AHDB

AHDB’s Marco Winters believes genetics could be one of the most influential factors on the carbon footprint of the dairy industry.

So much so, the development board launched the EnviroCow index last autumn to express the transmissibility of key environmental credentials from a bull to his daughters.

There is also a strong correlation between traits that are good for the environment and the overall profitability index, he adds.

Below, Mr Winter talks through the practical considerations and tools available for breeding for net zero.

Genetic improvement in productivity

Commercially, productivity remains an important trait, and breeding more efficient animals also has a positive impact on the environment.

Practically, this might mean smaller animals, which require less input to be efficient, but are still capable of producing good yields.

Breeding for longevity also plays a role: the longer a cow can stay in the herd, the fewer replacements are needed.

Fewer replacements mean fewer animals emitting greenhouse gases and a lower carbon footprint.

There are breeding values available for longevity, so farmers can breed for it directly. But for underlying longevity it is important to have animals in the herd that are fertile, free from disease and productive.

This can be achieved by a combination of direct breeding and practical herd management.

A new index worth considering under the productivity umbrella is Feed Efficiency.

The less animals feed, the less fermentation and methane are produced – which will lower the emissions of the national herd.

For Holsteins, the Feed Advantage index shows which bulls are more likely to transmit good feed efficiency to their daughters, again enabling farmers to feed less.

Improved fertility

The Fertility index allows farmers to breed for improved fertility directly. They should also maintain fertility at a herd level by using techniques such as heat detection systems.

Semen fertility is an area of ongoing work. More and more farms are using sexed semen and breeding companies are doing more to ensure semen is of optimum quality to get cows in-calf.

Reduced age at first calving

First calving at 24 months (rather than when older) means less methane is emitted during the rearing stage, when animals are eating, but not producing milk.

This is not targeted directly through a breeding value, but relies on ensuring growth and weight targets are met during heifer rearing.

To target a lower first-calving age, the first step is to ensure adequate colostrum is given at birth.

This should translate into a better-performing heifer that is more likely to be capable of calving at a lower age.

Again, this has environmental and financial benefits, with a lower calving age often associated with better lifetime performance and lower rearing costs.