MPs have warned that the Government's moves to tackle irresponsible dog ownership do not go far enough.
Plans to close a loophole which allowed dog owners to escape prosecution if the animal attacked someone in a private property have been announced.
Backed by the Environment, Food and Rural Affairs Select Committee, it said the plans fell short of creating a "comprehensive and effective regime for tackling the increasing problem of out-of-control dogs".
Dr Simon Harding, of Middlesex University London, interviewed illegal and legal dog owners as well as gang members as part of his research.
The research found that dangerous dogs are being bred by young men as a business asset in drug deals, debt collection and for their gang image.
A 16-year-old boy told him: "It's not just a dog, it's a half bull mastiff and half pit bull. I'll probably get another - we are looking to breed it - and we would get about £2,000 per dog."
Another boy, 17, said about pit bulls: "People know that if you are breeding you are making money from them."
Dogs that are classed as 'dangerous' are being bred a business asset in drug deals, debt collection and for their gang image, according to new research.
- The Dangerous Dogs Act is a law introduced in 1991 following a spate of attacks by aggressive or uncontrollable dogs.
- Dangerous dogs are classified by type, not breed, which means that a dog’s physical appearance will determine whether it’s deemed to be prohibited under the law.
- If your dog is seized by the police and found to be a banned type, the court can use its discretion to place them on the list of exempted dogs.
- This means that instead of them being destroyed, you can own them provided you follow certain conditions.
- The dog has to be muzzled and kept on a lead in public, they must be registered, insured, neutered, tattooed and microchipped.
- Defra has announced that all dogs must be microchipped from 2016.
- Changes to the law will also allow owners of dogs who attack on private property to be prosecuted.
Dangerous dogs are being bred by young men as an asset in drug deals, debt collection and for their gang image, according to new research.
More young men were using mastiffs, pit bulls, akitas and other aggressive dogs as a "commodity" for security and making money in gangs, the Middlesex University study found.
The study found the most aggressive dogs could be sold for more than £400, with owners building up their pet's muscles with vitamin supplements and even injecting them with steroids for fights.
The study, which will be presented to the British Sociological Association annual conference today, also found there has been a rise of 551% in hospital admissions for dog bites since 1991.
The Home Office has defended its plans to put dog measures in anti-social behaviour legislation rather than a dedicated Bill.
The six leading vets and animal charities have written to Home Office Minister Jeremy Browne to say they were "very concerned" at the proposed replacement of Dog Control Orders with less specific anti-social behaviour measures.
Allowing untrained council workers or police community support officers to issue orders "could lead to compromises in animal welfare or even make dog behaviour worse due to lack of understanding in these areas", it added.
Charities have spoken out against the government’s proposed new dangerous dog measures – planned in the aftermath of the death of 14-year-old Jade Anderson – warning that they could "cause more problems than they solve".
The six leading vets and animal charities said they were "extremely concerned" that the Home Office planned to put dog measures in anti-social behaviour legislation rather than a dedicated Bill.
MPs in the environment, food and rural affairs committee last month said the government had "comprehensively failed" to tackle irresponsible dog ownership.