A guinea pig broke out of its enclosure at an animal sanctuary and mated with 100 females – leaving them all pregnant.

The two-year-old rodent – which has been nicknamed Randy – is set to become a father to around 400 babies in the coming weeks.

Workers at Hatton Country World in Warwickshire were left wondering when they discovered all 100 female guinea pigs were pregnant after an inspection last week.

The males and females are usually kept apart but staff discovered an exhausted Randy taking a snooze in a pile of straw and realised he was the culprit.

The animal park, which already has 300 male and female guinea pigs, could see the population more than double in the next few weeks.

Manager Richard Craddock said: "One of our male guinea pigs managed to find his way into the female enclosure and had a very good time by the looks of it.

"We suspect a child may have placed him back in the wrong pen by accident after stroking him or Randy may have somehow broken out of his enclosure to get to the females.

"We don’t know how long Randy was in the female enclosure but it could have been several weeks which would have given him time to go round the entire female population.

"Staff did comment he looked a little thinner than before. He has now re-joined his male friends, clearly he’s got a lot of bragging to do.

"He must have been quite a busy boy to get round that many girls."