A study from Queens University Belfast has stated that the carbon footprint of British pig farming has reduced by almost 40% in the past 20 years.

The carbon footprint from pig farms is relatively low.

Pig systems contribute about 10% to the total greenhouse gas (GHG) emissions produced by livestock.

However, pig systems can also contribute significantly to eutrophication of water ways and emissions from slurry spreading and storage.

The research, which was funded by the EU, found that animal feed accounted for 75% to 80% of the carbon footprint of farms and changes to feed have the potential to alter the carbon footprint.

Replacing soya imported from South America with homegrown crops such as rapeseed and sunflower meal was reported to have a "significant mitigating effect on environmental outputs" in this study.

Nutrient availability

The addition of synthetic amino acids and enzymes also improved nutrient availability, reduced nutrient excretion and boosted animal productivity by 30% in some cases.

These supplements were also reported to reduce levels of phosphorus in run-off to water from pig manure by over 20%.

Advancements in animal breeding had a significant impact on carbon footprint reduction.

Breeding leaner and faster-growing pigs lowered the carbon footprint by 20%.

The study was led by the Institute of Global Food Security at the university and also collaborated with other UK institutions.

Twenty years (2000-2020) of data from Great Britain from the Agriculture and Horticulture Development Board (AHDB) was used to carry out an inverted model, a significant step in carbon research.

Prof Kyriazakis who led the research said that the carbon footprint of livestock farming has been declining "under the radar" for the past 20 years.

“We hear a lot these days about the need for farmers to reduce their carbon outputs for the sake of the environment, especially as it applies to beef and dairy cattle farming. There is much more attention focused on ruminant food systems as they produce higher GHG emissions.

“But I believe there are important lessons to be learned from this study - not only for better environmental management as it relates to pig farming, but potentially for all livestock systems.

"Some of the improvements identified in this study could potentially be applied to other animal systems, which would ultimately help move our collective agriculture systems towards a carbon-neutral model."

This research could play an important role for Irish agriculture as we prepare to tackle the implications of the climate bill.