A dog owner dumped an emaciated and dying animal in the garden of a house in Bristol.

The RSPCA said the state of the Yorkshire terrier was "one of the worst cases of neglect" the charity had ever seen.

The animal charity has launched an investigation in a bid to trace the person responsible for the act.

The gaunt and severely dehydrated female dog was found by a resident of Wyndham Crescent, Brislington, in their garden on May 2.

A veterinary examination at the RSPCA Bristol Animal Clinic also found the elderly terrier to have a matted coat and to be suffering from conjunctivitis.

The female's hind legs were too weak for her to stand, and she had faecal soiling all over her rear-end as well as a large untreated hernia hanging from her underside.

The RSPCA said its vets had no choice but to put the animal to sleep to spare it any further suffering.

Residents in Wyndham Crescent said they were appalled and shocked after the RSPCA revealed details of the incident last night.

Postman Philip Court, 59, said: "It's terrible. It's hard to believe that somebody would do that. There are a lot of animal lovers here so this will upset a lot of people."

Retired Valerie Beacham, 66, said: "I am disgusted – it just beggars belief. If they can not afford to keep the dog there is always somewhere you can take them. Just dumping her was cruel."

Full-time mum Amy Smith, 21, said: "It's absolutely shocking. I love animals and I find it unbelievable that somebody can treat an animal like that. They need to be found and punished."

Dog lover Gerard Shipway, 66, who is retired, said: "I don't know why people have animals if they are not going to look after them. If you don't want a dog, take it to a dog's home. This was disgusting behaviour."

Retired Linda Bridges, 61, added: "This was absolutely wicked but nothing surprises me any more."

Describing the state of the terrier, RSPCA Bristol veterinary clinic manager Mandy Stone said: "When you are a part of the RSPCA, you see some terrible sights but this dog must be one of the worst cases of neglect I have ever seen and she was so matted it was hard to recognise which end of the dog was which.

"This poor little creature was in a collapsed and distressed state and she has simply been dumped in a stranger's garden and left to die. Luckily she was found quickly and although nothing could be done to help her, at least she was prevented from suffering any further and given some dignity."

The RSPCA has appealed for information in a bid to trace the person responsible for the dog's care and discover how she came to be where she was found.

RSPCA chief inspector Becky Griffiths, who is leading the group of inspectors who are investigating, said: "We have made some initial inquiries but no one has recognised the dog so far, which suggests that she was probably abandoned some distance away from where she was living.

"There is no excuse for allowing any animal to get into such a state and it appears she has not received even the most basic of care, which owners have a legal responsibility to give to their pets under the Animal Welfare Act.

"I would urge anyone with information about this animal to contact the RSPCA so we can ensure that no other animals are suffering in this way."

Anyone with information should contact the RSPCA on 0300 1234 999.