A report released Tuesday by the California Horse Racing Board on a spate of horse deaths at Santa Anita found that no illegal medications were used on the animals and 39 percent percent of the 23 fatalities occurred on surfaces affected by wet weather.

However, the report found no singular cause for the deaths.

The long-awaited report focused on 23 deaths as a result of racing or training between Dec. 30, 2018, and March 31, 2019. Seven more deaths occurred from April 1-June 23, 2013, but weren't included in the report. Another seven deaths occurred at the fall meet last year, including Mongolian Groom in the Breeders' Cup Classic on national television. The fatalities roiled the industry and led track owner The Stronach Group to institute several reforms involving safety and medication.

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Nine fatalities have occurred this year at the track in Arcadia, where a decline in the horse population has led to fewer races being run.

“There has been a 64% reduction in catastrophic injuries at Santa Anita Park this year, and we have not had a single fatality during racing on our main track for the entirety of this season,” The Stronach Group said in a statement Tuesday. “While the first number represents a positive development, the second number is always the goal. We welcome the opportunity to work together with our industry partners to implement the suggested reforms and to make 2020 a year we can all be proud of.”

The report found that 19 of 22 horses' catastrophic musculoskeletal injuries (CMI) included proximal sesamoid bone fractures, which are related to racing and training intensity. Twenty-one of those 22 cases showed “evidence of pre-existing pathology” that is presumed to be associated with high exercise intensity, which predisposes horses with CMI to catastrophic injury.

“The indication is horses are overtrained and overraced,” Dr. Rick Arthur, the racing board's equine medical director, said on a conference call.

Other key findings in the report were that several trainers said they felt pressured to run their horses, although “none blamed the track itself for any fatality,” and there was no evidence of animal welfare violations.

The report found that a majority of trainers hadn't reviewed necropsy reports on their horses and many didn't possess “good working knowledge of anatomy.” Also, record-keeping by trainers was “poor” except in a couple instances. The report also noted that in several cases investigators suspected that someone else was overseeing horses' care other than the listed CHRB-licensed trainer.

Arthur said anatomy will be part of trainers' 12 hours of continuing education that are required to renew their license.

Rick Baedeker, CHRB executive director, said the rules to obtain a trainers' license already have changed. Now a person has to serve a year-long apprenticeship under a CHRB-licensed trainer and appear before the track stewards to obtain a full license.

Among the recommendations in the 76-page report are to establish strict criteria for canceling racing based on weather; to require continuing education for trainers; and to seek industry support for research into sesamoid bone and fetlock injuries, which caused the majority of the fatalities.

“We're moving to reform racing as best we can over the next year to 18 months,” CHRB chairman Greg Ferraro said on the call.

The report suggested that Santa Anita continue to consider replacing its dirt track with a synthetic surface. The racing board mandated synthetic tracks in the state several years ago, but it proved to be a failure.

“I don't think you're going to see us mandate anything in the near future,” Ferraro said. “Until you come up with a surface you're pretty confident on, I don't see the investment going forward.”

The report listed 47 recommendations, 12 of which are already in the regulatory process. Most involve establishing protocols for training, racing and when to cancel racing, moving toward digital record-keeping and transparency in medical records. It also requests a look at how the use of the riding crop, or whip, and breakdowns may be related.

“We have very good confidence that many of the recommendations will be implemented,” Arthur said.

The report details all 23 horses' cases, with notes about their veterinarian history and a list of possible contributing factors. The names of horses, trainers, owners, jockeys and veterinarians were withheld because various reports are confidential under California law.

The report said seven complaints will be filed alleging violation of failure to turn in daily vet reports, and three complaints will be filed alleging training without a proper license.

The racing board said it issued more than 70 subpoenas to trainers and vets for documents, while over 100 interviews with trainers, jockeys and vets were conducted.

The report was issued a day after the sport was rocked by a federal investigation that revealed systematic and widespread doping of horses. The indictments named 27 trainers, veterinarians and drug distributors, including prominent East Coast trainers Jason Servis and Jorge Navarro.

No California-based trainers were named in the indictments, and California was not among the locations listed where the alleged doping took place.

However, Baedeker said the board has opened an investigation into charges in the federal investigation that relate in any way to California. He said the board retains post-race urine samples for two years and can test any of them retroactively, as well as take action against anyone found guilty of conduct detrimental to racing.