Pig processors could face significant costs as the government considers alternative stunning methods
The government is proposing to ban high-concentration carbon dioxide stunning of pigs, a method used on around nine in ten animals slaughtered in England and Wales, amid warnings that alternatives could sharply increase costs for pork processors.
The proposals, announced by Defra on Monday (26 October), aim to reduce animal suffering before slaughter but could require major investment in new equipment and changes to processing operations.
A 2024 Food Standards Agency survey found that 90% of pigs were stunned using high-concentration CO2, highlighting the scale of the proposed transition.
The government wants the pork industry to adopt more humane alternatives, including argon gas and automated electrical stunning, following scientific evidence linking CO2 exposure to pain, panic and breathing difficulties.
Farming Minister Stephen Morgan said improving welfare at slaughter was essential to maintaining public confidence in British food production.
“We are a nation of animal lovers - pigs are intelligent animals that deserve to be treated with care and respect throughout their lives including at slaughter,” he said.
“The public want to know the meat they buy in the shops is produced in a way that supports high standards of animal welfare. These plans will help deliver that and reduce unnecessary suffering.”
The proposals follow recommendations from the independent Animal Welfare Committee, which previously called for high-concentration CO2 stunning to be phased out.
Committee chair Madeline Campbell described its continued use as “ethically unacceptable” when more humane, legally permitted alternatives were available.
“The evidence-based argument for moving away from the use of high concentration CO2 on animal welfare grounds is incontrovertible,” she said.
However, the proposals could prove controversial within the pork industry, with processors facing potentially substantial costs and practical difficulties in replacing existing systems.
An AHDB-commissioned report published in March warned that alternative stunning methods could increase costs from around 42p per pig using CO2 to as much as ÂŁ1.49 with argon gas.
Electrical stunning was estimated to cost approximately ÂŁ1.11 per pig, while processors could also face expensive equipment upgrades, disruption to production lines and reduced processing capacity.
The report also raised questions about whether alternative systems could deliver consistent welfare outcomes at commercial scale without creating additional handling or staff safety concerns.
AHDB pork sector director Mark Haighton previously stressed that the industry was not opposed to change, but warned against introducing new requirements without sufficient evidence.
“Any future transition must be evidence-led, properly resourced and delivered over a realistic timeframe to ensure it results in genuine welfare gains rather than unintended setbacks.”
The National Pig Association (NPA) has also raised concerns about the commercial viability of alternatives and the potential impact on British pork's competitiveness.
Responding to the March report, NPA chief policy adviser Katie Jarvis warned that imposing additional costs on domestic processors could leave them disadvantaged against overseas competitors.
“We must avoid forcing change domestically, whilst our global competitors continue to use existing stunning and slaughter methods.”
The concerns are particularly significant given that the European Commission has indicated it does not currently plan an equivalent ban, potentially leaving British processors operating under different requirements from their European counterparts.
The Association of Independent Meat Suppliers has also previously challenged the proposed phase-out, arguing that alternative methods could introduce additional handling stress and welfare risks.
Defra has been working with pig processors, equipment manufacturers, gas suppliers and animal welfare organisations since April 2024 to examine the feasibility of introducing alternative methods.
Discussions have focused on the practical challenges, financial implications and how to minimise additional costs for consumers.
Mr Morgan said the government recognised the need to help businesses adapt.
“We are committed to supporting farmers and businesses make this transition which will bring long-term benefits.”
The government believes moving away from CO2 could also reduce the industry's dependence on gas supplies vulnerable to international disruption.
Concerns over potential shortages linked to conflict in the Middle East earlier this year highlighted the risks associated with global supply chains.
The proposals form part of the government's wider animal welfare strategy for England, which includes commitments to improve standards for farmed animals throughout their lives and at slaughter.
However, no ban has yet been introduced, and the government has not confirmed when the existing method would be phased out.
A consultation launched on 26 October will examine the welfare benefits, costs, feasibility and potential timescales, recognising that businesses will need time to adapt.
Farmers, processors, welfare organisations and other stakeholders have until 21 December 2026 to submit their views before ministers decide how to proceed.