Golden Tempo won the Kentucky Derby on Saturday, making Cherie DeVaux the first woman to train the winner of the opening leg of the Triple Crown.
"Only in these days of political correctness could such an overturn occur," Trump tweeted.
Country House, a 65-1 long shot, was declared the Kentucky Derby winner after first finisher Maximum Security was disqualified.
In 1968, a drug test led officials to controversially disqualify Kentucky Derby winner Dancer's Image.
A Texas woman is celebrating, after hitting an improbable Kentucky Derby jackpot on Saturday, May 5, 2018.
Always Dreaming won the 143rd Kentucky Derby on Saturday on sloppy track at Churchill Downs in Louisville, Ky.