Sydney, Nov 5 (IANS): A small group of activists launched a protest in Sydney's Martin Place Tuesday to highlight the cruel treatment of many horses in the thoroughbred racing industry -- on the most important date in Australia's busy racing calendar.

Melbourne Cup Day is Australia's best-known horse-racing event and is held on the first Tuesday of November every year, reports Xinhua.

The national event is popularly dubbed as "the race that stops a nation". It is an annual public holiday in the state of Victoria and sees millions gamble on the winner and join workmates and friends at the boisterous pubs that broadcast the race.

However, Sydney office workers were given a small taste of the dark side of Australia's multi-billion dollar racing industry when Greens NSW MP John Kaye led demonstrators in a concerted push to highlight the treatment of animals in the racing industry.

Kaye told Xinhua that the industry was couched in "grim" statistics.

"People should enjoy the Melbourne Cup but we encourage them to spare a thought for the thousands of thoroughbred racehorses that are discarded and sent to the knackery each year.

"Many participants in Melbourne Cup celebrations today are blissfully unaware of the grim fate facing thousands of injured and failed racehorses," he added.

According to the Australian Greens, of the 18,000 foals that are born in Australia each year, 70 percent will never make it on to a racetrack.

Kaye said that while some owners look after their horses after their racing careers, thousands of thoroughbreds deemed to be "too slow" or economically unviable are either abandoned or sent to the knackery.

"Of those horses that survive to have a racing career, many suffer injury, illness and deprivation," he said.