Reducing nitrogen, phosphorus and ammonia emissions key for pig sector

Dr Ramon Muns, who leads the pig research programme at the Agri-Food and Biosciences Institute (AFBI), has highlighted a range of changes that can be made to support greater sustainability in the sector.

His assessment comes on foot of a recent report by the Centre for Innovation and Excellence in Livestock (CIEL), led by AFBI’s Professor Elizabeth Magowan, which has highlighted key mitigations that the UK’s pork industry can undertake to reduce emissions.

The research, delivered in collaboration with scientists and researchers from Queen’s University Belfast, Scotland’s Rural College (SRUC) and Rothamsted Research, provides pragmatic advice to farmers and producers in a range of sectors – including the pig sector.

Commenting on the difference that pig farmers and producers can make, Dr Muns said: “While pig systems are responsible for relatively low levels of greenhouse gas emissions compared with other livestock systems, it is important to keep working towards greater sustainability in pig production.

“Emissions of nitrogen, phosphorus and ammonia from pig systems remain a key challenge for the sector. As the recent CIEL report has highlighted, better feed use efficiency (i.e. how well the pig and the herd as a whole utilise feed) and reducing feed wastage on farms are key strategies to reduce overall emissions from pig production. However, the ingredients in the diet itself will have the greatest impact on lowering both the carbon footprint of the system as well as the nitrogen and phosphors excretion from the pigs”.

Highlighting the major changes pig farmers can make Dr Muns went on: “Lowering crude protein levels in a fattening pig’s diet will reduce nitrogen excretion and ammonia emissions. Data from our research at AFBI shows that, on average, there is a 10% reduction in ammonia emissions for every 1% reduction in dietary crude protein. However, any reduction in dietary crude protein level should be discussed with an expert nutritionist to ensure diets are balanced correctly for amino acids to prevent an impairment in the growth rate and efficiency of pigs.”

The pork sector plays a significant role in the Northern Ireland’s agricultural economy with the sectors contribution in 2020 valued at £216.9m.

While the impact of the GHG emission per pig is relatively low, compared to the beef, dairy and sheep sectors, there are still some important contributions that can be made by farmers in this sector.

Mitigations against emissions in the sector can usually be divided into three distinct areas, mitigations that relate to the animal, to the feed and to the manure.

The CIEL report lays out nine options for pig farmers and those in the pork sector that if implemented partly or wholly could help make a significant difference to the GHGs emitted into the atmosphere. These were then modelled to see what options had the greatest impact.

The report contains many of these mitigation measures modelled on a farm and has shown very positive results. For more details visit the AFBI website.