A German university has been ordered to move a group of guinea pigs which have kept homeowners up all night because of their noisy orgies.

Thirteen male and female specimens live together in a large outdoor cage at Muenster University in north-west Germany.

However, following complaints from nearby homeowners who said they cannot sleep because of the noise of their wild-sex sessions, they were this week the subject of a hearing in the city's Administrative Court.

Yesterday, a judge ruled the cage was too close to neighbouring houses.

It is just two metres from where gardens begin and by law should be at least three metres away. 

A sign on the door of the guinea pigs cage reads: 'These animals live in non-committal, mixed-gender groups and mate with every possible partner.'

Pavo Rueder, 69, whose house borders directly on to the guinea pig area, said: 'Don't we know it.

'They are unbelievably loud and stink to high heaven. It's unbearable.' 

'They go at it like, well, guinea pigs on Viagra. There's no sleep to be had at all.'

A university spokesman said it was examining the judge's ruling.

'We hope this doesn't mean the end of our valuable research,' he added.