Macau authorities took in more than 500 greyhounds abandoned following the closure Saturday of Asia's only legal dog-racing track.

The former Portuguese territory has been the only place in China where dog racing is legal. However, betting on dog races at Macau's Canidrome — a tradition of more than 50 years — soured after animal rights groups accused the stadium of mistreating the dogs and euthanizing ones that underperformed on the track. It was ordered closed on Saturday.

The Macau government said that the Canidrome faces legal measures under the Animal Protection Act for failing to move the dogs from their shuttered premises. Authorities found on the company's property 533 greyhounds, including a dozen suffering from skin disease and other conditions, and are now making arrangements for their care.

Macau ordered the Canidrome to move out of the downtown area last year amid urban redevelopment efforts.

The demise of the stadium, which saw massive crowds at its peak in the 1960s, comes as China seeks to cut Macau's dependence on the high-rollers who helped propel the city's transformation from a seedy backwater into a global gambling powerhouse. The city is now shifting its focus toward middle-class Asian tourists.

The Canidrome is owned by Angela Leong, a billionaire Macau businesswoman. She did not comment immediately Saturday.

Animal rights activists have expressed concern about the fate of the race dogs, most of which were bred in Australia. People for the Ethical Treatment of Animals, or PETA, urged Macau to give custody of the greyhounds to local animal protection groups that will put them up for adoption.