Los Angeles County's Santa Anita Park is standing firm against calls to cancel the rest of its racing season after the deaths of two more horses over the weekend, bringing the number of horses that have died at the track since December to 29.

In a highly unusual move Saturday, the California Horse Racing Board asked the park to scuttle competition for the seven remaining race days to "provide the industry more time to fully implement announced safety initiatives and perhaps additional ones."

But park owner The Stronach Group along with the Thoroughbred Owners of California and California Thoroughbred Trainers released a joint statement Sunday saying the racetrack will remain open until the season ends on June 23.

"Since wide-sweeping reforms have been instituted at Santa Anita, catastrophic injuries have dropped considerably compared to earlier this meet," the statement read, adding: "To be clear, there are no acceptable losses, and every day we work toward ending all serious injuries. But the reality is that our improvements and changes have been effective."

Santa Anita suspended racing for much of March, when the toll of horse deaths neared two dozen — twice the rate of the previous year — and as it worked to figure out why so many horses were dying.

Before reopening on March 29, the park announced a series of changes it planned to implement, including limiting the use of pain or anti-inflammatory medications and treatment for horses and improving early detection of preexisting health conditions. Santa Anita had already pledged to bring in outside experts on a regular basis to review its dirt, turf and synthetic course surfaces.

The park says those moves have already reduced catastrophic injuries "by 50 percent in racing and by more than 84 percent in training."

Since the park reopened, seven more horses have died there.

On Saturday, a horse named Formal Dude was euthanized after "taking a bad step" in a mile race, according to the official race chart. An examination revealed a fractured pelvis, reports The Daily Racing Form.

In response to the death of the 4-year-old gelding, the state Horse Racing Board issued a recommendation Saturday that Santa Anita "suspend racing for the seven remaining race days but that they allow horses to continue to train during that period."

Santa Anita issued its refusal on Sunday. That same day saw another horse fatality: Truffalino pulled up during the third race of the day, and the jockey dismounted just before the 3-year-old filly collapsed. The horse died of a suspected heart attack.

In an emailed statement, the California Horse Racing Board said it "does not have the authority to suspend a race meet or remove race dates from a current race meet without the approval of the race track operator or without holding a public meeting with ten days public notice."

At the time Santa Anita suspended races in March, questions swirled about whether heavy Southern California rains and poor track conditions were causing the horse injuries and deaths. But other experts weren't so sure.

"There's no obvious answer. So every question is being asked: Is it the surface? Is it the horses that are running on the surface?" Rick Baedeker, executive director of the California Horse Racing Board, told NPR's All Things Consideredin March.

"Racing has become more competitive over a period of time," Rick Arthur, equine medical director at the School of Veterinary Medicine at the University of California, Davis, told NPR's Tom Goldman. "Horses are worked faster and there are fewer horses to fit the slots that are available. So there's more pressure on the horses to race more frequently."

People for the Ethical Treatment of Animals says that horses, with their massive frames supported by spindly legs, simply aren't built to withstand the rigors of training and racing. The organization notes that injuries such as strained tendons or hairline fractures can be difficult to diagnose before a horse is run again.

PETA has called for a nationwide suspension of racing until greater safety measures are put in place. "Trainers, owners, and veterinarians have recklessly controlled racing and imperiled horses for too long, and those days must come to an end," Senior Vice President Kathy Guillermo said in a statement.

And while just a handful of race days remain this season, Santa Anita is set to host the prestigious Breeders' Cup in November. Amid the spate of horse deaths, according to the LA Times, the Breeders' Cup committee is considering moving the event to Churchill Downs in Kentucky.

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