Crufts has been accused of perpetuating cruelty to animals after a German Shepherd with a sloped back was named best in breed by judges.

Hundreds complained to the Kennel Club over footage of Cruaghaire Catoria which shows the dog with a slanting back seeming to impede the movements of her rear legs.

Many viewers criticised Crufts for allowing the three-year-old dog, bred by Susan Cuthbert, to enter and win the competition.

A statement from the RSPCA said it was "shocked and appalled" to see a dog with "such poor conformation that it could not move freely winning Best of Breed".

"We would question how the dog had been allowed to have qualified for Crufts. In doing so, this dog, like all Crufts competitors, would have been awarded on at least one other occasion, suggesting this is unlikely to be an isolated incident.

"Fault cannot lie solely with the judge at Crufts but is also the responsibility of those who have previously awarded this dog and enabled it to progress so far in the process to be appearing in the Crufts showring."

The RSPCA added: "Many other dogs at Crufts showed visible signs of poor health and/or discomfort as a result of their exaggerated conformation. For example, the winner of the Toy group, a Pekingese, was panting heavily and struggling to breathe. This illustrates why there is an urgent need to review the breeding and judging process."

Crufts Dog Show 2016 Show all 20 1 /20 Crufts Dog Show 2016 Crufts Dog Show 2016 Bichon Frises prepare for the show Crufts Dog Show 2016 A Yorkshire Terrier peers out from her blanket as she prepares for the Crufts PA Crufts Dog Show 2016 Terriers sit curled together on their grooming table Getty Images Crufts Dog Show 2016 Sonia Merate trims her poodle Layla PA Crufts Dog Show 2016 Eurasian dogs looks out of their stalls Getty Images Crufts Dog Show 2016 Lhasa Apso named Casper wears a wooly hat PA Crufts Dog Show 2016 A handler shows a Maltese during the first day of the Crufts Dog Show in Birmingham Reuters Crufts Dog Show 2016 Mable the Manchester Terrier arrives with her owner for the Crufts Dog in Birmingham) Getty Images Crufts Dog Show 2016 Hungarian Vizsla named Fenix arrives for the Crufts in Birmingham PA Crufts Dog Show 2016 A Standard Poodle jumps up to its handler Reuters Crufts Dog Show 2016 A dog owner arrives with Dalmatians on the first day of the Crufts Getty Images Crufts Dog Show 2016 A poodle jumps as it arrives at the Crufts Rex Crufts Dog Show 2016 A pug named Pickle arrives for the Crufts PA Crufts Dog Show 2016 A Bulldog looks from its cage Reuters Crufts Dog Show 2016 Yorkshire Terriers on show at the annual Crufts Dog Show in Birmingham EPA Crufts Dog Show 2016 A Chinese crested terrier waits for its competition class Rex Crufts Dog Show 2016 A dog performs in the agility section of the annual Crufts Dog Show in Birmingham EPA Crufts Dog Show 2016 A woman walks around with her dog o her shoulder EPA Crufts Dog Show 2016 A Bichon Frise looks out of its pet stroller Getty Images Crufts Dog Show 2016 An owner sits alongside her Eurasian dog in its stall on the first day of the Crufts Getty Images

A statement from the Kennel Club said: “Concern for the health of German Shepherd Dogs is reflected in the fact that the breed is classed as ‘category three’ under the Kennel Club’s Breed Watch scheme. Many of the category three breeds have seen vast health improvements but we know that some breeds still have further to go.

“We will be looking at what support we are giving to particular breeds to ensure continued improvement, and we will also be reviewing judges who appear to disregard the health instructions they are given since they play a significant part in this process.