An unusual sight: a cow with the stripes of a zebra. However, the above cow was not painted because it looks strange, but it was used to deter flies. Because what appears? The stripes of a zebra reduce the number of painful fly bites by 50 percent. This can be read in the scientific journal Plos One.
Scientists have for some time believed that stripes, such as those of a zebra, are the way to keep flies away from cattle. It is a cheap and environmentally friendly alternative to pesticides.
Previous studies have already shown that the white stripes confuse the motion detectors of a fly. In concrete terms, this ensures that the flies approach the cattle at high speed, failing to slow down in time, preventing them from landing.
White and black stripes
Some Japanese researchers put the test to the sum. They collected six cows. Two of them got white stripes (a), two got black stripes (b). The remaining duo served as a control group and did not get any color (c).
The stripes, which were painted on the cows with water-based paint, remained for three days. The test was then repeated. The experiment lasted nine days in total, with each cow once white, once black and once without any stripes.
The cows were most lucky when they got the white zebra stripes. While the unpainted cows had an average of 128 fly bites, the cows with zebra stripes had only 55. The cows with black lines were bitten 111 times on average.
The typical fly-repellent behavior – such as the shaking of the tail or the head – also decreased in the cows with white stripes. In 30 minutes, they exhibited such behavior on average forty times. For the other cows that were on average 53 to 54 times.
The stripes would already be a relief for horses, cows, and farmers. “Biting flies are the most harmful vermin for livestock worldwide,” the researchers said. “The economic impact of biting flies on a cattle farm in the US was estimated at $2.2 billion a year.”
How can such a small insect have such a significant effect? Annoying flies prevent cows from grazing, eating and sleeping peacefully. It becomes even worse when the cows get heat stress and want to escape from the insects. In addition, cattle can also be injured.