It’s too hot for horses to handle, the California Horse Racing Board ruled.

Extreme heat in this weekend’s forecast prompted the racing board to cancel the opening weekend of thoroughbred horse racing at the California State Fair in Sacramento. High temperatures are expected to range from 100 to 110 degrees, forecasts show.

Horse racing will resume on July 21 at Cal Expo.

It’s the first fair activity to be removed from the schedule due to opening weekend’s triple-digit temperatures. No other activities have been canceled due to heat, according to a fair spokeswoman.

“Once you get into certain numbers, whether it’s horse or human, there’s risks of the body being able to cool,” said Dr. Jeff Brea, the racing board’s equine medical director. “Similar to humans, you can have heat strokes or heat stress disease associated with the high heat temperatures with exercise.”

Horses begin feeling discomfort at a heat index of 130 and danger reaches a critical level at an index of 180, according to the California Horse Racing Board’s inclement weather policy. The heat index, calculated using temperature and humidity, is expected to reach a high of 146 on Saturday, according to Larry Swartzlander, director of racing at the fair.

Concerns over air quality, which is forecast to dip into the “unhealthy for sensitive groups” category on Saturday, also led to the board’s cancellation of this weekend’s horse racing.

In 2020, a horse at Grants Pass Downs in Oregon collapsed and died after racing in triple-digit heat.

Fifty to 60 horses were supposed to compete in about 24 races this weekend, according to Swartzlander. To make up for the lost races, the fair plans to add three or four extra races every day when races resume on July 21.

Last year, horse racing at the fair brought in $28.4 million across nine days of racing, Swartzlander said. With only six days of races this year, he’s anticipating fewer bets.

Horse safety top of mind after high-fatality Kentucky Derby

Churchill Downs, the home of the Kentucky Derby, suspended horse racing for the rest of the season this May after the deaths of 12 horses this year. Seven of the horses died in the lead-up to the final race of the Kentucky Derby, the most-watched horse race in the country.

In the 2022-23 fiscal year that ended June 30, 26 horses died in California from injuries sustained while racing or training, according to the racing board’s latest data. That’s a 76% decrease from four years ago, when 107 horses died from racing or training injuries. Between 8,000 and 10,000 horses train and race in California each year.

Brea said an increased commitment to horse health and safety from horse owners, trainers, veterinarians and regulators has led to the decrease in injuries.

Canceling the horse racing “shows leadership, that rather than focus on what is important to the fair from an economic impact, the focus is now that it’s not fair to the horses, so we’re not going to race the horses,” Brea said.