A 13-stone bullmastiff who was featured on a TV show for badly behaved mutts has landed his Black Country owner in court after attacking a dachshund in the street.

Owner Karen Reid, a 46-year-old grandmother, insisted today that Henry’s behaviour had been “totally out of character” and that he had done really well on the programme.

The two-year-old bullmastiff starred on “Dog Borstal” on BBC Three after Mrs Reid, a manager for Spire Healthcare, contacted the programme because she had problems walking him. But when a film crew returned for a progress report they ended up trying to drag Henry away when he went for Bruno the dachshund.

Mrs Reid said: “I have two dogs, Henry and Nella, an old English mastiff, and when I took them for walks they would pull so hard that, effectively, they were walking me.

“I went on the show to see if there was a way of calming them down a bit, not because they were badly behaved in any other way.

“The advice they gave me was to walk them totally separately – and it worked. Henry did really well in the show.”

It was when the film crews returned to check up on Henry at his home in Wednesbury that the attack took place. Henry ran up to the dachshund – a hearing dog for its deaf owner – and bit it, breaking the skin on its stomach. The dog was being walked by Diane Nutt, also from Wednesbury, and her two young grandchildren.

Mrs Reid said: “It was a totally isolated incident – it has never happened before or since. I tried to find the lady owner of the dog and offer to pay the vets bill and say sorry but the police wouldn’t give me the details.

“I don’t know why he did it, only that it was a very hot day, when I would not normally have walked him and he was over-excited by the BBC crew who were in a rush to get the filming over with.”

Mrs Reid of Holden Road, Wednesbury, was ordered to pay £250 in compensation to Mrs Nutt and court costs of £50 when she appeared at West Bromwich Magistrates Court last Thursday. She admitted failing to control Henry.