Owners who fail to socialise and obedience-train dogs at an early stage are fuelling frightening levels of problem behaviour in their pets, according to new research.

Children should be taught at school how to be good owners in the face of research showing fundamental gaps in knowledge about animal welfare, the PDSA said, with 1.3 million dogs across the UK displaying "problem behaviour".

In Scotland, 31% of dog owners said they have been bitten or attacked by a dog, with half saying they knew someone else who had been injured by a dog.

The charity said it was concerned that 16% of dog owners north of the Border said their pet showed signs of problem behaviour, including growling or snarling and aggression towards people and other animals on a regular basis.

The study also found 56% of dogs in Scotland did not attend training classes in their first six months of life, down 5% on the national average.

The charity's research warns that the primary cause of the anti-social behaviour is a lack of socialisation and obedience training when dogs are young.