Review links post-stun hypertension to welfare risk in sheep and cattle

Blood pressure may be playing a bigger role in stun failure risk than many veterinary professionals assumed. A new systematic review in The Veterinary Journal found that both captive bolt and electrical stunning in sheep and cattle are consistently associated with hypertensive responses, rather than the immediate circulatory collapse some might expect. The authors argue that these blood pressure surges could help preserve brain viability long enough for some animals to regain consciousness if the stun is ineffective or bleeding is delayed, adding a cardiovascular dimension to long-standing welfare concerns around slaughter practices. That conclusion fits with earlier work showing head-only electrical stunning in sheep can produce a marked rise in arterial pressure, while effective monitoring after captive bolt remains essential because unconsciousness is not guaranteed by the method alone. (sciencedirect.com)

Why it matters: For veterinary professionals working in food animal welfare, slaughter oversight, research, or policy, the review reinforces that stun efficacy can't be judged by equipment type alone. Existing guidance from EFSA emphasizes monitoring for signs of consciousness after stunning, during shackling and hoisting, and during bleeding in bovines, and the new review adds support for rapid, well-executed follow-up steps to reduce the chance of recovery. In practice, that means renewed attention to stun quality, timing to sticking, staff training, and use of animal-based indicators of unconsciousness, especially where reversible electrical methods are used. (efsa.europa.eu)

What to watch: Watch for this review to be cited in future welfare guidance, slaughter auditing protocols, and research on how cardiovascular responses interact with time-to-stick and indicators of consciousness in cattle and sheep. (efsa.europa.eu)