People should make sure they properly socialise their pets by training them with dog food treats and classes to prevent it them from becoming aggressive.
The PDSA has revealed that over one million dogs in the UK display aggressive behaviour towards people or another animal on a weekly basis.
Research also showed that 4.1 million dogs never went to training classes and 25 per cent of owners who had their dog from it being a puppy did not adequately socialise it.
Sean Wensley, PDSA senior veterinary surgeon, said: "PDSA is urging owners who may have concerns about their pets’ aggressive behaviour to seek professional advice as soon as possible.
"Anyone with a young dog should, without exception, make a commitment to socialising and training their pet using effective and humane methods."
Findings of the survey also found that 87 per cent of people think owners should face stricter penalties if their dogs attacks a person or animal, while 35 per cent of owners said they would consider getting rid of their dog if it became aggressive.