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33 min ago 3 min read
The UK government has proposed phasing out the use of carbon dioxide (CO2) to stun pigs before slaughter, citing animal welfare concerns and proposing alternatives including argon gas and automated electrical stunning.
High-concentration CO2 is widely used in British slaughterhouses, but an independent expert assessment found it causes pigs pain, respiratory distress and fear while they remain conscious.
“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,” said Farming Minister Stephen Morgan.
The proposals follow an assessment by the government’s Animal Welfare Committee (AWC), which recommended prohibiting high-concentration CO2 stunning.
“It was the clear view of the AWC that the continued use of high concentration CO2 when more humane, legally permitted alternatives are available is ethically unacceptable,” said committee chair Madeline Campbell.
CO2 dissolves in the moist membranes of pigs’ eyes, noses and respiratory tracts, forming carbonic acid that activates pain receptors. It also triggers a strong respiratory response, causing hyperventilation, gasping and air hunger.
Pigs may even vocalise and attempt to escape before losing consciousness, according to animal welfare agency RSPCA.
Around 90% of pigs reared in England and Wales are stunned using high-concentration CO2, according to the Food Standards Agency’s 2024 Slaughter Sector Survey.
The government has proposed argon stunning and automated electrical systems as alternatives. Argon avoids the same pain and respiratory distress associated with CO2, while correctly applied electrical stunning can induce unconsciousness almost instantaneously.
However, switching methods come with new challenges, including the cost of new equipment, potential changes to processing speeds and the need for individual restraint with electrical systems.
The Agriculture and Horticulture Development Board has highlighted the potential costs. Its modelling of a representative high-throughput pig processing plant estimated stunning and slaughter costs of £0.42 ($0.56) per pig using CO2, compared with £1.49 ($1.99) using argon with additional capacity and £1.11 ($1.48) using electrical stunning.
Processors have also raised concerns about commercial viability and the potential for UK producers to lose competitiveness against imported pork produced under different welfare requirements.
The government said it had been working with processors, equipment manufacturers, gas suppliers and animal welfare groups since April 2024 to assess the practicalities of a transition. A consultation on costs, feasibility and timescales runs until 21 December, with the AWC recommending a transition period of no more than five years.
gasworld has contacted the British Meat Processors Association for comment on the proposals and their implications for UK processors.
