The abattoir (slaughterhouse) is where the animal welfare standards of the entire production system culminate in a final, irreversible welfare event. Despite its critical importance, abattoir welfare has historically received less systematic attention than on-farm welfare — a gap that welfare science, regulation, and industry are now working to close.
The scale of industrial slaughter is enormous — approximately 80 billion land animals are slaughtered annually for food globally, with billions more fish. In the UK alone, approximately 1 billion animals are slaughtered annually. Each individual experiences the slaughter process — however brief — and the quality of that experience matters.
Animal welfare at slaughter encompasses multiple stages, each with specific welfare requirements:
Official veterinarians (OVs) are required in EU-regulated slaughterhouses to oversee welfare compliance. CCTV in slaughterhouses is now mandatory in England and supported by evidence of its impact — abattoirs with CCTV show significantly better welfare compliance than those without. Animal welfare officers (AWOs) employed by slaughterhouses provide continuous monitoring rather than periodic OV visits.
Stunning effectiveness — ensuring animals are insensible before sticking — is the critical welfare metric. Controlled atmosphere systems for pigs (using CO2 or high oxygen gas mixtures) show different welfare profiles than electrical stunning. CO2 systems require pigs to travel through aversive atmosphere while conscious — a significant welfare concern. Non-aversive gas alternatives (nitrogen, argon) are preferred but less commercially widespread.
Religious slaughter without prior stunning — practiced for halal and shechita (kosher) requirements — is controversial from a welfare perspective. Evidence consistently shows that effective pre-slaughter stunning followed by neck cutting achieves more rapid insensibility than cutting without stunning. Many Muslim authorities accept reversible stunning that does not kill the animal before slaughter. The welfare policy challenge is balancing religious freedom with animal welfare imperatives.