Calves are, (due to their larger body surface in relation to their weight), less sensitive to heat than cows.


Depending on the THI (Temperature Humidity Index), the absolute temperature at which calves get into trouble can vary.

For me there is heat stress in calves as soon as the ambient temperature at animal level does not fall below 23 ° Celsius at night.


Heat stress calves absorb less food while their immune systems are weakened. This results in poorer growth, increased disease susceptibility and higher mortality than at moderate temperatures. Heat stress mainly affects calves when too little cooling occurs at night.

Especially with hutches and shelters, ventilation is often a problem in the summer ... 


1. Provide shade:

Hutches and shelters under shady trees or under a roof is desirable. If this is not possible, use a sunscreen. Placed approximately one meter above the Hutches and shelters, this already results in a temperature reduction of 3 to 4 ° Celsius in the Hutches and shelters.


2. Spraying water cools:

I am absolutely NOT in favor of nebulizing. If you want to apply misting, make sure that the hutches and shelters remain dry inside and that the calves have enough space to move freely inside and outside the hutches and shelters.


3. Position the opening of the hutches and shelters to the east:

When the hutches and shelters are facing east, the airspeed is highest and direct sunlight in the hutches and shelters is lowest during the day.


4. Sufficient distance between the hutches and shelters:

In order to obtain sufficient air circulation, the distance between the hutches and shelters must be at least 1.50 meters. If the hutches and shelters are opposite each other in several rows, the distance between the rows must be at least 3.5 meters.


5. Place the rear of the hutches slightly off the ground:

When using hutches without a fixed bottom, you can place the hutches on bricks or concrete blocks at the rear. This increases the air circulation at floor level.


6. Provide continuous fresh water:

Provide the calf with fresh water at all times. Water improves digestion and compensates for moisture loss through sweating.

Calves suffering from diarrhea in particular need extra fluids. Especially at high temperatures, these animals are extra sensitive to heat stress.


7. Give calves extra energy:

Due to heat stress calves use more energy. This while their appetite decreases due to the heat….


8. Feed small portions of concentrate over several feedings:

In hot and humid conditions, concentrated feed spoils quickly, while the calves eat less in warm weather.

Remove unabsorbed (concentrated) food after one day. Moist or wet concentrate spoils very quickly.


9. Perform the necessary treatments in the morning:

Then you, the calves and the environment are not overheated yet.


10. Dry, clean and fresh bedding:

Dry, clean and fresh litter reduces heat development due to heating in the manure.

At very high temperatures, even sand can easily reduce heat development without the risk of disease.