A third horse involved in the production of Luck, HBO's racing drama, had to be euthanized Tuesday, prompting the suspension of filming involving horses in the show's second season.
Unlike the first two horses, which became severely injured during racing scenes, this horse was not racing or being filmed at the time of injury.
The 5-year-old thoroughbred had passed a soundness check by a licensed veterinarian at the start of the day, but during a walk through the barn, the horse began prancing, then reared up on her hind legs, fell back and hit her head. The injury was deemed so severe that the animal had to be euthanized.
While it is not uncommon for thoroughbreds to be euthanized following injury at the race track, "it is very uncommon in the world of film and television," Karen Rosa, the senior vice president of the American Humane Association's Film & Television Unit, tells PEOPLE.
American Humane, which insisted that filming with horses cease, set more rigorous guidelines following the first two horse deaths on Luck. "To HBO's credit, they put the protocols in place and we have not had an accident in the year that they have been in place," Rosa says. New protocols include radiographing all horses before they race, and only allowing short runs during racing scenes.
"From the very outset of this project, the safety of the animals was of paramount concern to us," HBO said in a statement. "Everyone associated with Luck cares deeply about the well-being of the horses who are so much a part of the heart and soul of the production."
Activist group People for the Ethical Treatment of Animals called for a halt to filming. Because the investigation is still ongoing, American Humane could not say whether it would recommend that Luck no longer use horses on set.
"It's too premature to jump to any conclusions," Rosa says. "We have to really take a look at all of the specifics and ask if there is something more that can be done to possibly prevent something like this from happening in the future. Or, as happens in the real world, is this truly an accident that can happen, even with all the protocols and guidelines and safety in place?"
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