SWISS computer scientists think they have found a way to increase milk production – they have created a gadget through which cows can communicate that they are in heat – by texting the farmer’s mobile phone.

Cattle experts say the machine could solve one of the biggest problems facing dairy farmers, as every moment a cow is in heat and not pregnant is a missed opportunity. It is thought that the device, which is being tested before going on sale early next year, could revolutionise the production of milk.

Up until now, farmers have had to use visual inspections to determine the best time to bring in the bull or to artificially inseminate.

Claude Brielmann, part of the team at Bern University of Applied Sciences, said: “Farmers need to spend time with their herd to work out the best time for their cows. That can be hard with a large herd.”

The electronic heat detector is a series of sensors, some of which are implanted in the genitals to measure small changes in body heat. Others are put around the cow’s neck to measure body motion as another sign a cow is in heat is that it becomes agitated.

The gadget contains a SIM card, enabling a text to be sent to the farmer at the crucial moment.

British cow consultant Bruce Woodacre said: “If the device works, it will improve fertility rates quite dramatically and increase the annual milk yield of every cow.