Dairy farmers hoping to increase milk production could try installing a sound system in their cowshed, according to psychologists from the University of Leicester. Friesian cows, it seems, produce more milk than usual while they are listening to relaxing music.

Carrying out their study over nine weeks at Bishop Burton Agricultural College in Humberside and Lincolnshire based LCAH Dairies, Dr Adrian North and Liam MacKenzie played a musical repertoire of differing tempo to one thousand Friesian cows from 5am to 5pm.

The results appear to prove the anecdotal belief that music can relieve stress in animals. The cows responded well to calming numbers such as REM's Everybody Hurts, or Beethoven's Pastoral Symphony, and their milk yield rose by 3% after listening to the relaxing tunes. This amounts to about one and a half extra pints (0.73 litres) in the average dairy cow.

More upbeat songs such as the Wonderstuff's Size of a Cow made no different to yield size, however.

MacKenzie explained to BBC News that the pair would now investigate the effects of music on other farmyard animals: "Most theories of music preferences are based on humans [...] We found that slow music improved milk yields perhaps because it relaxes the cows in much the same way as it relaxes humans."