It's this passion for taming which makes Le Portier arguably the best animal trainer in the world.

CNN: Meet the man who turns big cats into movie stars

Westfelt's uncle, Tony Gentry, was a Hollywood animal trainer who brought the young Cheeta back from a scouting expedition in Africa in the 1930s.

NPR: Cheeta, Screen Star for the Ages

Before addressing any behavior issues, animal trainer Kristen Collins of the American Society for the Prevention of Cruelty to Animals (ASPCA) says pet owners should start with a thorough veterinary exam.

CNN: Solve common pet behavior problems

"It's always been my goal to prove that the Derby wasn't just him getting lucky, " Animal Kingdom trainer Graham Motion said.

WSJ: Americans eye win at world's richest horse race

Went the Day Well (20-1) has some long odds, but he followed the same path to the Kentucky Derby that trainer Graham Motion set for last year's winner Animal Kingdom: Went the Day Well and Animal Kingdom both won their last prep race, the Spiral Stakes.

WSJ: Kentucky Derby: How to Eliminate 19 Horses

But even Godolphin and its trainer Saeed bin Suroor insist the Americans are the favorites, notably Animal Kingdom.

WSJ: Americans eye win at world's richest horse race