Monitor Temperature Humidity Index to prevent cow heat stress this summer

Temperature humidity index (THI) is a critical tool that could help dairy farmers looking to optimise the health, productivity, and welfare of their herd during the summer.

THI is a metric that combines environmental temperature and humidity levels to provide an indication of the likelihood of heat stress among cattle.  

Heat stress occurs when high temperatures and humidity exceed the cow’s ability to effectively regulate body temperature.

What is the impact of Temperature Humidity Index on dairy cows?

The effects of heat stress on dairy cows are wide-ranging and can have long-lasting consequences.

When cows are too hot, they will naturally eat less. Over time, this reduction in input will lead to a decrease in milk production due to the lack of available energy.

Prolonged periods of heat stress can also have an impact on fertility and weaken the cow’s immune system, making them more susceptible to disease and lameness.

Read more: Could heat stress be affecting your bottom line.

How farmers can reduce the impact of Temperature Humidity Index on dairy cows?

Tracking THI over time can reveal important patterns and trends that can help inform long-term on-farm management decisions.

For example, analysing THI data may reveal that sheds or sections of housing are consistent ‘hot spots’ in humid or warm weather. These environments can increase the risk of heat stress affecting cattle.

This insight means farmers can proactively plan and prepare for these challenging conditions. This may include using fans, adding a positive pressure tube ventilation system and keeping the sun off cattle using screens.

Read more:  Navigating livestock ventilation solutions  

Some common strategies to help reduce the risk of heat stress include:

• Improving barn ventilation and airflow to enhance cooling
• Providing shade and access to water to help cows regulate their body temperature
• Adjusting feeding schedules and rations to avoid the heightened risk of reduced feed intake
• Implementing cooling systems, such as VentTube Cool, to actively cool the cows

THI monitoring tool

Galebreaker has launched a free,  online tool which shows real-time THI data from dairy farms across Europe. The website also provides the key features of each shed where data is captured which can help farmers to gain insight into the factors that can influence THI levels within buildings.

The site also contains a handy THI calculator to help you calculate the THI on your farm. Visit THI-Live here.