CHRB: No Spike in Sudden Equine Deaths
The California Horse Racing Board said the number of non-musculoskeletal sudden deaths of horses in racing and training at California racetracks has not spiked, contrary to an article published in the Paulick Report Wednesday.
Dr. Rick Arthur, the CHRB's equine medical director, said the number has been relatively constant over the last three years: 20 sudden death in fiscal year 2010-11; 19 in 2011-12; and 17 to date for 2012-13 (the fiscal year ends June 30).
Furthermore, Arthur said sudden deaths “are not rare. In a 1994 scientific paper on the CHRB necropsy program (Johnson et al, EVJ 26:327-330 1994) put the sudden death rate at 9%. The sudden death fatality rate over the last few years is roughly the same after several years of lower rates. An international multi-center jurisdictional study (Lyle et al., EVJ 43:324-331 2011) had the proportion of sudden death fatalities varying from 3.5%-19% in the jurisdictions reporting.”
Paulick Report used statistics from a report prepared by the California Animal Health and Food Safety Laboratory System for a February meeting of the CHRB Medication and Track Safety Committee. Those statistics – four deaths in 2008-09 and six in 2010-11 – were for cardiac failure and did not represent the total number of sudden deaths as we reported.
A February CHRB report did point out an increase in cardiac failure sudden deaths: 11 in 2011-12, up from four in 2008-09 and six in 2010-11. The number of cardiac failure sudden deaths for the current fiscal year is not available.
CHRB commissioner Bo Derek repeated that information at Thursday's board meeting, stating twice: “The number of sudden deaths has not spiked in California.”
Derek also said, “No trainer or trainers have been mentioned in our discussions.”
Paulick Report, Bloodhorse.com and New York Times have reported that Hall of Fame trainer Bob Baffert had seven horses suffer non-musculoskeletal sudden deaths while racing or training in Southern California over the past 18 months. That number is verified through mandated necropsy reports obtained through a public records request by the Paulick Report. Four of the Baffert sudden deaths were during the 2011-12 fiscal year and three during the current 2012-13 fiscal year. They do not include any horses euthanized after suffering catastrophic injuries.
Cause of death for four of the seven Baffert horses was some type of heart or cardiac failure. One was pulmonary edema, one was from equine protozoal myeloencephalitis, and the final one was from a massive abdominal/thoracic cavity hemorrhage.
The latter horse was found in toxicology testing to have trace amounts of diphacinone, an anticoagulant used in rodenticide, or rat poison.
The CHRB said one other horse had trace amounts of a rodenticide. That horse, based on Equibase charts and comments in a necropsy report obtained by the Paulick Report, was the 7-year-old gelding Truism, who collapsed in midstretch of a race at Santa Anita Park on March 2, 2013. Truism was trained by Mike Mitchell.
According to the CHRB necropsy report, Truism also suffered a severe internal hemorrhage, including hemoabdomen, hemothorax, and mesenteric.
The rodenticide detected in the liver of Truism was brodifacoum (also an anticoagulant). “Because of the small amounts detected, the exact amount could not be detected,” the necropsy report states. “It is usually assumed that if an anticoagulant rodenticide is detected on a post-mortem specimen (as in this case), it needs to be associated with an apparent coagulopathy for which no other cause is found, in order to be considered significant. In this case, there was hemorrhage of no other apparent cause, and a coagulopathy is suspected, although not confirmed. These findings are therefore strongly suggestive, but not conclusive of brodifacoum intoxication.”
The CHRB said the rodenticides discovered in trace amounts of the two horses were not the type used for pest control at the Southern California racetracks where the horses died.