Livestock Heat Stress: Recognition and Response

Heat stress affects multiple livestock species during hot weather; recognising signs and responding rapidly prevents acute welfare emergencies and productive losses.

Key Facts

Pigs are particularly vulnerable as they cannot sweat effectively and rely on panting
Dairy cow milk yield decreases by 10-20% during moderate heat stress before clinical signs are obvious
Poultry heat stress kills millions of birds annually in single events
The Temperature Humidity Index (THI) predicts dairy cow heat stress at threshold values

Welfare Considerations

Heat stress responses in livestock develop rapidly during hot weather and can progress from discomfort to life-threatening condition within hours. Early recognition — increased respiration rate, reduced feed intake, congregating near water, and shade-seeking — enables intervention before acute welfare emergency. Management responses including shade provision, water availability, ventilation, and in severe cases active cooling are progressive interventions appropriate to the THI experienced. Pre-planning for hot weather prevents reactive scrambles during emergencies.

What You Can Do

Monitor temperature-humidity index during hot weather and implement pre-planned management responses
Ensure shade, ventilation, and ample clean water are available before hot weather arrives
Support heat stress emergency response planning requirements in livestock welfare assurance schemes