Is a Thoroughbred race, for a filly running against colts more grueling on the females, physiologically?

Question

I'm wondering if there should be serious consideration for fillies to run races that are geared to only females, such as the Maiden races.....after yesterday's tragedy, although it is said to have been a freak accident, I am wondering if these physically grueling horse races are becoming inhumane. It seems as though the earnings (AND "life insurances" of these horses) have become more important than the lives and safety issues of race horses.....are fillies physically more fragile than colts? Out of 20 entries, only one was a filly.....there HAS to be a reason for this, or else we would be seeing even ratios of male vs. female in these races. Any feedback or answers would be appreciated, thank you.

Answer 1

Rags To Riches was a filly that beat all the boys last year in the Belmont Stakes.  That is a more grueling race then the Kentucky Derby.  She's perfectly healthy and is now retired and in foal.  And in other countries fillies race against colts all the time.    

Maiden races aren't geared toward females.  A maiden race is a race for horses of either s*x that haven't won a race yet.

Answer 2

Fillies are generally slower then colts, 8 Belles was bigger then most of the males, and the one thing that really can cause problems in a mixed race is if the mare is in heat it can drive colts wild.

The one reasion why it might be tougher is that the males are genreally faster, but the Derby showed that she was by far the 2nd best horse that day.

Answer 3

the number of colts born each year is always greater then the number of fillys , so statistically there will always be more colts running.

a maiden race  doesn't mean its for fillys only , its for all horses that haven't won a race.