Japan: painting cows like zebras protects them from insects, study says

Yamagata is a very agricultural area in the north of Japan with many cattle farms. And just like in the rest of the country, breeders fear the stress that insect bites will cause their animals. These are areas where there are many horse and anthrax flies, which also feed on animal blood. They attack cows that spend a lot of time trying to chase them away with head or tail gestures. These actions mean less time for grazing at rest and, at the herd scale, this means less productivity for the farmer.

Scientists have therefore tried to reduce these insect attacks without necessarily using insecticides. EBetween 2021 and the end of last year, they experimented on animal fur. They painted cows like zebras to see if the insects changed their behavior. Pto transform the hair of cows, itJust like people who go to the hairdresser, we use bleaching powders. So the scientists produced liters of bleach water and drew large white stripes five centimeters wide on the cows to make them look like large zebras.

Three times less movements to repel insects

They then observed their behavior for months. They found that cows painted as zebras made significantly fewer unpleasant movements against biting insects. They move only five times per minute, while in the same field a cow without changing color moves 16 times per minute to chase these insects. They concluded that horse and anthrax flies were disturbed by these color changes. The cows are protected by a kind of optical illusion.

These zebra stripes do not hinder the cow in her relations with other animals, that was one of the concerns of breeders. But neither the Yamagata researchers nor the farmers noticed any change in behavior in the herd. Solid colored cows are very well received by zebra cows.