Lila, Glee, and Pistache lie down in their barn for their daily nap after feeding on corn, grass, and grain, and taking in the air from two giant fans, in the midst of a heat wave in France.
At an altitude of 780 meters, in Saint-Martin-en-Haut (east), the outside temperature is 34° Celsius, but the two fans, 4.5 meters in diameter, cool the interior of the barn by a few degrees. 35 dairy cows.
“Due to the evolution of the climate, farmers are constantly adapting”, says Nicolas Joannon, owner of the farm, explaining that when temperatures rise, the “thermal stress” causes the cows to eat less and produce “a little less milk.
“If we ensure good conditions to overcome these episodes, immediately after the heat wave, the animals will recover their initial level of performance and will continue to produce quality milk for consumers”adds the 34-year-old man.
Dairy cows are very sensitive to temperature. From 22° centigrade and 50% humidity, they accumulate heat in their body and can produce two fewer liters of milk than the 28 to 38 liters per day per cow.
To prevent this, Nicolas Joannon installed two fans on the roof of his herd’s stable in 2020, an investment of 9,000 euros ($9,230).
The two metal giants automatically start up based on temperature, and as the heat rises, their speed increases until they reach full capacity.
The rancher, who owns 45 hectares, points out that “fewer cows are slaughtered since the fans are on”.
“At 22° centigrade, the cow can adapt, but from 28°-30° centigrade, it will suffer”explains Alexandre Batia, 44, a ventilation expert with the local Rhône Conseil Élevage association, which advises farmers.
180 liters of water daily
“There are more and more files from farmers waiting to be conditioned” stables and one farm in five has already taken the step, says Batia, who accompanied Joannon in her installation.
But these devices must “support” the “good practices”. “Livestock farmers should prioritize evening feeding or add additional troughs”since cows can drink up to 180 liters of water per day.
Bertrand Fagoo, from the French Livestock Institute (Idele), points out that fans are a “secondary improvement factor”which should be installed after opening up the barn more and providing more shade.
“There is no need to remove hot and stale air in a closed area”insists the 53-year-old researcher.
Spraying water on the animals can be another option to limit heat stress, but it carries the risk of increased humidity, explains Alexandre Batia.
In his opinion, stables must also be ventilated “homogeneous”as “Otherwise, the cows will gather in the most favorable areas, blocking the circulation [del aire] and accumulating heat, which is not the desired objective”.