Pig & Poultry Review Emissions have reduced for both outdoorbred pigs and indoor units
Big reduction in carbon footprint of pig farms
T
he carbon footprint of British pig farming has reduced by almost 40% over the last 20 years – making pork a much more environmentally friendly meat for consumers, suggests a study. The independent research is based on conclusions from historic data on livestock systems across England, Scotland and Wales. Because data on agricultural inputs was sparse, a new methodology was developed to retrospectively estimate their contribution. The study was led by the Institute for Global Food Security (IGFS) at Queen’s University Belfast, Northern Ireland. Agricultural systems have come under pressure to reduce their carbon footprint and the UK government has set a target of carbon neutral farming by 2050. Research leader Ilias Kyriazakis said: “The reason this research is so significant is that it shows an area of livestock farming where carbon footprint has been reducing over the past 20 years, almost under the radar. “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 greenhouse gas emissions.”
Calculating the carbon footprint of a farming system is a complex metric. It involves a large number of indicators including what kind of fuel is used on the farm, how soil is cultivated, the style of land management and the types of animals and crops farmed. Although the environmental impact contribution per unit of meat from pig systems is relatively low, pig meat is the meat type most produced and consumed globally. Scientists says it therefore contributes significantly to several forms of environmental impacts. The study estimates that pig production systems contributed 668 mil-
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Calculating the carbon footprint of a farming system is a complex metric
lion tonnes of carbon dioxide to greenhouse gas emissions in 2013 – roughly 10% of emissions produced by livestock systems overall. In addition, pig production systems are considered to be major contributors to the acidification and eutrophication of the environment. This is due to emissions of nitrogen and phosphorous from manure storage and spreading. The new study suggests an overall drop in the carbon footprint across the British pig sector. This amounts to a 37% reduction in emissions for indoor production systems and a 35.4% reduction for outdoor-bred pigs.
Animal feed The role of animal feed was found to be central to the environmental impact of pig farms – accounting for between 75-80% of carbon footprint. Changes to feed ingredients, therefore, had the continued on p34
How better productivity reduces emissions Improvements in animal performance have contributed significantly to the reduction in the environmental impact of pig production. This includes better breeding for leaner and faster growing pigs, increases in number of piglets born per sow per litter and reductions in overall mortality Advances in breeding leaner and faster-growing pigs alone was found to lower carbon footprint by 20%. Professor Kyriazakis conducted the research in collaboration with scientists from other UK institutions, interrogating publicly available Agriculture and Horticulture Development Board (AHDB) data from Great Britain from 2000-2020.
He said he believed it is the first time inverted modelling has been used to investigate the environmental impact of any livestock system. The findings have been published in the Agricultural Systems journal following peer review. “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,” said Prof Kyriazakis. “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.”
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