While Ireland and England are horrified at the thought of eating horses, 1bn people do so all over the world.

Some 6,033 horses were slaughtered for meat in 2015, so last year’s figure is a 25% increase. However, at the height of the recession, in 2011, 24,000 unwanted horses were slaughtered for meat here.

Many thoroughbreds who failed to make it on the racing track ended up in abattoirs at the start of this decade, when the Irish economy began to slide. Most of the carcasses are exported to Europe, where they are eaten as burgers or steaks, or even roasts.

ISPCA chief inspector Conor Dowling said it can be kinder to euthanise an animal humanely rather than leave it open to neglect or abuse.

“We’ve seen so many animals abandoned in bad condition over the past 10 years,” said Mr Dowling. “It is certainly favourable for an animal to be humanely destroyed, or slaughtered for meat or put to sleep by a vet.

“It is a sad situation that this is what is required, because of over-population, but, sometimes, it might be the responsible thing to do.”

Globally, consumption has been on the rise since 1990, with horse meat commonly served in China, Russia, Central Asia, Mexico, Holland, Switzerland, Italy, Japan, Belgium, and Argentina.

Mr Dowling said sport and race horses are now being slaughtered for food in Ireland.

“It could be horses who have reached an age where they can’t perform anymore, or who don’t make the grade,” he said.

“Some might have some sort of injury and be healthy enough to make the trip to the slaughterhouse, but not to live on indefinitely.”

The recent scandal of horse DNA found in frozen beef burgers sold in Irish supermarket chains has affected the demand for the meat, and has tightened up regulations on the traceability of meat ingredients all over Europe.

In 2016, 1.6m cattle and 2.7m sheep were killed at Department-approved slaughter establishments.

A Department of Agriculture spokesperson said all slaughter plants whose meat is destined for human consumption must meet EU regulations relating to food safety and animal health and welfare.

France recently became the first country in Europe to vote to make CCTV mandatory in abattoirs.

Installation of CCTV is not mandatory in Ireland, but the Department of Agriculture said the slaughter process, and the handling of animals going to slaughter, takes place under strictly supervised conditions.

Veterinary Ireland said that Ireland’s meat inspection service, operated independently by the Department of Agriculture, ensures animals are inspected prior to slaughter and post-mortem.

“Veterinary Ireland maintains that veterinary involvement in the Meat Inspection Service provides the world’s highest standard of ante-mortem and post-mortem inspection, standards which most other countries can only aspire to”, said the chief executive of Veterinary Ireland, Finbarr Murphy.

Mr Dowling said the ISPCA would support CCTV regulation, but that the vets in abattoirs are the best way of ensuring animal welfare.

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