LONDON, Jan. 10 (Xinhua) -- Britain's biggest betting organisations have agreed a multi-million dollar deal to ensure a happy retirement for thousands of racing greyhounds, it was announced Thursday.

Betting companies, known as bookmakers, are investing nearly 4 million U.S. dollars a year to help welfare organisations care for the dogs when their racing days are over.

Britain has 21 licensed greyhound tracks, with the sport the sixth most watched across the country.

The funding will help greyhounds be better cared for as a result of a new deal worth.

Sports minister Mims Davies said the funding will contribute towards new tailored training for veterinary staff, the expansion of an injury recovery scheme to ensure more greyhounds can enjoy a full and active life following racing. It will also help provide more homes for dogs as they enter retirement through increased funding for the Greyhound Trust which rehomes around 4,000 racing dogs every year.

The extra money will also go towards improving safety across the nation's 21 licensed racetracks, kennel improvements and the provision of air-conditioning for trainers' vehicles to improve welfare standards.