Practical tips for managing heat stress in dairy herds

The significance of heat stress in dairy herds is often overlooked. While many farmers have experienced heat stress and seen its negative impacts on animal health and productivity, there is commonly a gap between acknowledging the problem and accepting it as a regional threat.

Recent survey findings from our A-SHED project, delivered with SRUC, Smartbell and Foods Connected, highlighted this with 84% of UK-wide respondents reported heat stress on their farms, yet only 74% perceived heat stress as an issue in their region.

This disconnect can lead to a lack of preparedness and a delay in implementing effective responses to tackle heat stress.

As temperatures rise, managing heat stress becomes critical to maintaining herd health and overall farm productivity. Fortunately, with the right precautions, heat stress can be mitigated. Below are practical tips to help you manage heat stress and protect your livestock.

Use heat stress index tools

Prevention is better than cure so utilising tools like THI-Live to help you track temperature and humidity levels and predict when conditions will start to impact your livestock. This can help you plan interventions ahead of time, such as adjusting feed schedules or intensifying cooling measures.

Improve ventilation and airflow

In cow sheds ensure good airflow. Proper ventilation helps dissipate heat and maintains a comfortable temperature for your cattle.

Natural ventilation should be the first line of defence against heat stress as a well-designed, naturally ventilated shed will achieve high air exchange rates. Check whether your livestock buildings are helping or hindering airflow through the shed’s side inlets and ridge outlets. Smoke tests can be used to identify dead-air zones. For a comprehensive building assessment consider booking an appointment with one of our Animal Welfare Advisors.

Natural ventilation relies on wind pressure and thermal buoyancy, allowing cooler outside air to move through the shed while warm, moist air rises and exits through the roof. Galebreaker’s retro-fittable VentRidge has been purpose‑engineered to overcome the limitations of traditional ridge systems such as cranked tiles which often fall short in removing warm, contaminated air.

To supplement natural ventilation, mechanical systems can also be introduced. Positive pressure tube ventilation systems like Galebreaker’s VentTube Cool help introduce fresh, cooler air at cow level, improving airflow. This reduces humidity, removes excess heat, and encourages cows to lie down, feed, and behave normally.

Increase water availability

Heat stress significantly increases water consumption, so ensure your cows have access to clean, fresh water. For every 100 lactating cows in hot weather, allow a daily supply of roughly 19,000 to 23,000 litres of drinking water.

Cows do not drink evenly through the day; they often consume up to 50% of their daily water intake after milking [1] so allow for ‘rush-hour’ drinking. Increase water trough capacity and provide multiple access points.

Consider placing additional water stations in areas where cows naturally queue, such as parlour exits, collecting yards and feed areas, to encourage drinking and prevent dehydration.

Adjust feeding times

During extremely hot periods, it might be beneficial to adjust feeding times. Feed cattle during the cooler parts of the day, such as early morning or late evening, to avoid adding heat load during the hottest hours. Also, avoid overfeeding as it can increase metabolic heat production. Feed more frequent, smaller portions to help cows digest better.

Monitor animal health and behaviour

Keep a close eye on your herd for signs of heat stress, including panting, drooling, and lethargy. Cows that are under heat stress may also exhibit reduced feed intake or become more aggressive. Early detection is key to preventing more serious issues like reduced milk production or even heat-related illness.

Provide shade and cool rest areas

Ensure cattle have access to shaded areas throughout the day, especially during peak heat hours. Ensuring cows have a cool place to rest can help regulate their body temperature, reducing stress and fatigue.

Consider breed and genetic factors

Some dairy breeds are more heat-tolerant than others. If you are in a region that regularly experiences high temperatures, it might be worth considering breeds that are better suited to hot conditions. Breeds like Jerseys and certain crossbreeds can often handle heat stress more effectively than others.

Equally cows bred for high yield traits are typically more susceptible to heat stress. They produce more metabolic heat, making it harder to keep their core temperature stable when ambient temperatures rise.

Next steps

Heat stress is an increasingly serious concern as weather patterns change. Addressing it requires a proactive approach. Why not speak to a member of Galebreaker’s Animal Welfare Team to book a shed ventilation assessment and install THI monitoring to enhance your ability to manage heat stress effectively.

Call Chloe or Grace on: 01531 637 900