Reports of cows suffering from fever and diarrhoea, while at the same time experiencing reduced milk production, are increasing on livestock farms in Switzerland, but the cause of this mysterious animal disease remains unclear, according to the federal authorities.

The Federal Food Safety and Veterinary Office (OSAV) “has taken note of reports indicating an increase in cases among dairy cows. Many farmers say their animals are showing fever and diarrhoea, often accompanied by reduced milk production,” but “the cause has not yet been identified.”

The authorities are carrying out investigations to determine whether the disease is caused by a metabolic or infectious factor. So far, however, no pathogen responsible for the disease has been identified and “no link has been found between the heat and the cases of diarrhoea,” according to the OSAV. In any case, high temperatures may affect the animals, particularly dairy cows, making them more vulnerable to disease.

Like other European countries, Switzerland has experienced heatwaves in recent weeks, accompanied by a significant decline in rainfall.

The OSAV reminded farmers that during hot periods of the year, animals must be systematically protected from high temperatures and provided with sufficient water and shaded areas.

At the same time, however, it stressed that such general symptoms as fever, diarrhoea and reduced milk production may also be associated with a highly contagious animal disease, and called on farmers to inform their veterinarian immediately so that the appropriate tests can be carried out on their herds.