Over the past few days, we've spoken to a number of farmers and veterinary practices across Ireland who have reported an increase in cases of heat stress and heat stroke in cows and calves. With warm weather continuing, now is the time to take extra precautions to protect your livestock.
Heat stress can affect beef and dairy cattle, young calves, sheep, and other livestock, leading to reduced performance, dehydration, illness, and in severe cases, death.
Why Heat Stress Matters
Unlike humans, cattle cannot cool themselves efficiently through sweating. Instead, they rely mainly on panting and increasing their water intake to regulate body temperature. During hot, humid weather, this cooling system can become overwhelmed, particularly in animals grazing in open fields with little shade.
Even a short period of heat stress can reduce feed intake, milk production, weight gain, fertility and overall animal welfare.
Signs of Heat Stress
Keep a close eye on your livestock throughout the day, particularly during the hottest hours.
Common signs include:
- Heavy or rapid panting
- Open-mouth breathing
- Excessive drooling
- Lethargy or reluctance to move
- Reduced grazing or feed intake
- Standing around water troughs
- Animals seeking any available shade
If you notice these signs, act immediately before the condition progresses to heat stroke.
1. Ensure Plenty of Shade
Where possible, move livestock into fields with natural shade from trees or hedgerows. If adequate shade isn't available, consider housing animals in a cool, well-ventilated shed during the hottest part of the day.
Spring-calving cows with calves at foot, heavily pregnant animals and young calves require extra attention during periods of high temperatures.
2. Check Water Troughs Regularly
Water is the single most important factor in preventing heat stress.
During hot weather:
- Check troughs several times a day.
- Ensure water is clean and flowing freely.
- Repair leaks or blockages immediately.
- Make sure all animals can access water without competition.
Research from Teagasc highlights that cattle can require 1.5 to 2 times more water than normal during hot weather, making regular checks essential.
3. Avoid Handling During Peak Heat
Moving cattle through collecting yards or handling facilities during the middle of the day increases their body temperature and stress levels.
Where possible:
- Move livestock early in the morning or later in the evening.
- Delay non-essential handling until temperatures fall.
- Minimise the time cattle spend standing in collecting yards.
What To Do If You Suspect Heat Stroke
If cattle are panting heavily, struggling to breathe or appear distressed:
- Move them immediately into a cool, shaded, well-ventilated shed.
- Provide constant access to fresh, cool drinking water.
- Increase airflow if animals are housed.
- Reduce further handling or stress.
- Supply electrolytes to help replace essential salts and fluids lost through excessive panting and dehydration.
- Contact your vet immediately for professional advice.
Prompt action can make the difference between recovery and a serious welfare emergency.
Prevention Is Better Than Treatment
Irish summers may be short, but heatwaves are becoming more common. Taking a few simple preventative measures—providing shade, checking water supplies, monitoring animals closely and acting quickly when warning signs appear—can help protect your herd and maintain productivity throughout periods of hot weather.
At Animal Farmacy, we're here to support Irish farmers with trusted livestock health products and practical advice to help keep cattle healthy all year round.