None of the four female jockey deaths in Australia in the past 14 months can be blamed on the rider, the Australian Racing Board says.

Chief executive Peter McGauran says two recent falls have been caused by horses breaking down and have nothing to do with gender.

"I understand there's a widespread perception throughout the industry, and even society at large that females are physically weaker than males," he said.

"But whether that be true or not, they are equally capable in riding skills and courage and aptitude."

The comments come as the Australian racing community mourns the deaths of two young female jockeys in two days.

Queensland rider Carly-Mae Pye, 26, died on Tuesday from injuries she suffered in a trackwork fall a day earlier.

South Australian apprentice Caitlin Forrest, 19, died in hospital on Thursday morning after a four-horse fall at Murray Bridge on Wednesday.

Champion jockey Simone Montgomerie died when her horse threw her to the ground on Darwin Cup day last August, while Desiree Gill was killed in a fall on the Sunshine Coast in November.

McGauran said in both accidents this week, the riders were in front when their mounts broke their legs.

"They are tragic deaths caused by 600-kilo horses racing at 60 kilometres an hour and bringing the girls to the ground," he said.

Star jockey Tommy Berry used Twitter to stress that female riders were just as capable as male jockeys.

Several high-profile racing industry figures are calling for a tougher response to safety concerns.

Melbourne Cup-winning jockey Chris Munce has questioned the high number of fatalities on Australian racecourses.

"Is it our style of riding? Shape of our tracks (tightness)," he tweeted.

Hall of Fame trainer Lee Freedman said it was time for drastic change in the sport, regardless of cost.

He said field sizes should be reduced, all horses should be strictly vet checked and penalties must be far stiffer for severe interference.

McGauran said there are work safety investigations, coroner's inquiries, horse autopsies and stewards' reports have been opened into both deaths.