MEET the latest weapon in the battle against rats.

Patterdale terrier Rock the Socks is so keen to catch rodents it is said he will “tear doors off their hinges” to chase them.

Owner William Walker says Rock the Socks – known affectionately at Rocky – is more effective than rat poison and less harmful to the environment.

Mr Walker runs the Canine Rescue Centre in Weston-on-the-Green, and said he knows all about rats. Rodents got into the engine of a van he owned and “devoured” its electrics just a week after it passed its MoT.

And he added: “Last week, I put down a big bag of seed and within an hour there must have been 20 rats inside.”

Last month a survey by the Rodenticide Resistance Action Group revealed a growing number of rats have a gene which makes them immune to all poisons legally used outside in the UK.

Eight out of nine rats sampled in Wallingford and the surrounding area were completely resistant to legal outdoor poisons.

In the UK, there are only about eight poisons which can be used outside because of the risk of secondary poisoning to birds of prey.

Oxfordshire pest controller Rob Eckton, of Pest Force, said he had seen a rise in resistant rats, but he did not normally use dogs to control them. He said: “It is not like in the old days, where dogs were used because everything in a house was open.

“Nowadays, rats get in through cavity walls and through the loft.

“Dogs are often used on pig farms, though, when they turn over those aluminium tunnels.”

Mr Walker said: “Rocky is a working dog, they are not pets. We are going back 50 years to the days when every house had a terrier.”

Mr Walker is even offering to rent out Rocky for £50 an hour.

Oxford City Council also offers a paid-for rat-catching service.

Over the last two years, the number of call-outs it received dropped from 1,386 in the year ending March 2011, to 914 in the year ending March 2012.

Charges were introduced in April 2011 to help counter a a £9 million cuts package.