Irish racing is to take place behind closed doors starting at Dundalk on Friday until 29 March, under special measures in response to the coronavirus outbreak.
Horse Racing Ireland made the announcement following Government advice on Thursday to contain the spread of Covid-19, including an instruction to limit external gatherings to less than 500 people.
After consultation with the Department of Agriculture, Food and the Marine and with industry stakeholders, HRI has imposed a number of restrictions to ensure that fewer than 500 people are on site at each meeting.
The measures have taken immediate effect, with the situation being kept under review.
HRI chief executive Brian Kavanagh said: "Public health is the number one priority and these restrictions will continue to be kept under constant review as we liaise with our colleagues in the Department of Agriculture, Food and the Marine and the Department of Health.
"The restrictions which we are announcing today will limit social interaction, but will allow a vital rural industry to continue to operate, protecting livelihoods and jobs."
The restrictions include access being limited to essential service providers and industry participants. There will be no catering services, on-course bookmakers or Tote services provided. Only trainers with runners can attend, with one owner and one groom per horse.
However, racing will be available to broadcasters as at present.
Leading Irish trainer Michael Halford gave the decision his full backing.
The Kildare handler said: "I think the main thing is we keep racing. We're very grateful that we are still racing and in the circumstances it makes sense.
"I'd agree with it 100%."
Cheltenham Festival-winning trainer Henry de Bromhead said: "If that's what they feel is the best thing to do, that's what we need to do.
"It's good the racing is continuing. If racing behind closed doors is our policy, we have to support it."
Gigginstown House Stud racing manager Eddie O'Leary welcomed the move.
"It's great because racing isn't a sport, it's a business," said O'Leary.
"The question they faced was do you cancel or what. What about the Derby and the Guineas? These are strange times and we're doing the best we can having it behind closed doors. No bookies, no public, just the industry, we've all got to survive in these strange times.
"I've heard people saying it should be stopped because it's only a sport, but it isn't - it's an industry and a lot of people's lives are depending on it."
In Britain, Patrick Vallance, the Government's chief scientific adviser, said cancelling large sports events is "not a major way to tackle this epidemic".
He said: "On average, one person infects two or three others.
"You therefore have a very low probability of infecting a large number of people in a stadium and a rather higher probability of infecting people very close to you.
"And that means that most of the transmission actually tends to take place with friends and colleagues and those in close environments - and not in the big environments.
"Though it is true that any cancellation of things can have some effect, if you then get a displacement activity where you end up with everyone congregating somewhere else, you may actually perversely have an increased risk, particularly in an indoor environment.
"So it doesn't mean you shouldn't at some point make the decision from a resilience point, but this is not a major way to tackle this epidemic."
At the Cheltenham Festival on Thursday, hand sanitiser stations continued to be well used, and course officials are looking forward to the completion of the four-day meeting on Friday, where the highlight will be the Gold Cup.