heat stress – 10 Tips & tricks

It looks like we are heading towards a warm and sunny summer! This week temperatures might even reach the 30 degrees Celsius. For humans the perfect temperature to sunbathe, but for your dairy cows heat stress is lurking! These temperatures are threatening for a newborn calf. Are you well prepared to protect them from the sun?


In the first month of a calf’s life its ideal temperature is around 15 degrees Celsius. Therefore, you can imagine that with tropical temperatures, in combination with high humidity, a calf experiences stress. The weather can make the body temperature of a calf raise up to 40 degrees Celsius! Next to that, calves will start sweating, heavily breathing and desiring more moisture.


Like human beings, on warm days, calves have the need to drink more and the appetite disappears. This is where the danger lurks. In order for a calf to cool down it needs a lot of energy. However, since he does not eat as much as he would normally do,  he misses out on a lot of energy. The result? A stagnating growth, which results in a lower milk production during the first lactation. What can you, as dairy farmer, do about this? How do you recognize the signals of heat stress? Read it all in our tips & tricks for preventing heat stress.

heat stress

symptoms of heat stress in calves


In essence, heat stress can be recognized the same way as in humans. Calves tend to become slow and walk less quickly to their drinking bowls. Furthermore, the calf has less appetite, which causes a decrease in food intake. Do you see that your calves are sweating and gasping? Intervene, heat stress is likely to be present already!

Tip 1 – Reposition your housing system to the shade

Sounds like a no-brainer but definitely one not to forget! Replace your calf hutches and pens to more cooling surrounding. Furthermore, you can decide to purchase a shadow canvas to stop the sun rays. When replacing your calf hutch, pay attention to the position of the sun during the afternoon.

calf iglo
Trio Kälberhütte

Tip 2 – cool the roof of the calf hutch


Besides the heat from direct rays of the sun you should also make sure that the heat doesn’t turn your calf hutch into a microwave. One way of cooling down your calf hutch is by sprinkling  cold water on the roof. Another decision to consider is when it comes to the purchase of your calf housing systems. For instance, Topcalf offers calf hutches with isolating roofs. These particular roofs can cool down the hutch with up to 10 degrees Celsius. Would you like to know more about this option? Ask our specialists for more information!

Tip 3 – position your calf hutches not too close to each other


By using more space between the calf pens the air circulation will be optimized. It’s recommended to keep at least a distance of 2 or 3 meters. Another trick is place a brick, or something similar, underneath your calf iglo. This way you stimulate a better air flow.

calf housing with perspective

Tip 4 – ensure a good air flow


Once again, like humans, calves love fresh air. Especially when the temperature outside rises. Recommended to have, at least, a wind velocity of around 2,5 m/s. There are plenty of ways to realize this. One way is to make use of fans. Do you have a Trio, Quattro or Quinto edition than you can also open the air slides. Another option is to make use of tube ventilation. Tube ventilation is pretty new to the market and uses excess pressure to ventilate the room. Air is sucked into the tube, which creates over pressure. Due to the holes in the tubes, the air will be realized across the entire barn or calf hutch.

Tip 5 – control regularly


Preventing is better than healing! By regularly controlling the temperature and humidity you can undertake serious actions when required. Especially when dealing with calves that suffer from diarrhea as they tend to be more dehydrated. In the table below you can see when heat stress occurs.

hittestress kalveren
Bron: https://www.dekalverhouder.nl/nieuws/Hittestress-ligt-al-op-de-loer#1
drinking calf

Tip 6 – create access to fresh and cold water


Something one should definitely not forget it the availability of sufficient fresh drink water. Are you running out of water? Then empty the bowl, clean it, and then refill it with fresh water. This way your calves always have access to fresh water.

Tip 7 – feed and muck out at different times


In order to decrease the amount of stress a calf experiences, it’s a good idea postpone your activities to cooler moments of the day. For instance, in the early morning or evening. Besides the fact that it’s more convenient for the dairy farmer, it is also less likely to trigger any stress moments. So, if needed, try to feed or muck out at different times than maybe usual. Also, special operations, like dehorning, should be postponed to a different date.

reinigen kalverbox
water nebulizer

Tip 8 – Cooling through water nebulizer

One of the newest methods of cooling in the agricultural sector is by using a nebulizing fan. This way you do not wet the calve but rather cool down the air around it. This system is already often applied to dairy barns. Feel free to ask our experts for more information!

Tip 9 – reduce the number of flies


Obviously, avoiding flies does not have a direct correlation with the body temperature of a calf. However, it does drastically reduces the amount of stress a calf experiences. In order to prevent a stagnating growth it is important to grab hold of all the available options. Flies love the heat, light, drought and food, just what calves like as well. By applying proper ventilation systems in your barn you will already reduce the number of flies massively. Be avoiding flies, you will also take out one of the reasons diseases spread. As we said, preventing is better than healing, hygiene is of high importance. A clean barn will not attract as many flies as a dirty one.

calf straw

Tip 10 –replace straw by sand or sawdust


The last tip we provide is about the bed a calf lays in. A thick package of straw will retain a lot of heat. As you would like to minimize the heat you should think of replacements that do a better job at reflecting heat. Good alternatives are sand or sawdust. Is it not possible to apply any of these two? Then refreshing the straw is a good idea! The mixture of urine and manure causes more heat and ammonia, and therefore should be cleaned regularly. As mentioned before, don’t do this during the heat of the day!

The central thread in fighting heat stress is by providing proper and fresh food, as well as a high quality calf hutch. By realizing a good climate your calf will not experience the heat stress and can continue to grow. Are you curious how we fight heat stress? Feel free to reach out to one of our colleagues. 


Hittestress komt niet alleen bij uw kalveren voor maar kan ook uw melkkoeien aantasten. Benieuwd naar het effect? Bekijk onze blog hier.

Share this page