NEW YORK — A border collie named Kelso rocketed to a win in the Westminster Kennel Club’s new agility competition Saturday night, while a husky mix called Roo! ran away with the recognition afforded to mixed-breed dogs at the nation’s premier show for the first time since the 1800s.

Shooting through tunnels, scrambling over ramps, weaving through poles as a tail-wagging blur and taking a tight turn with a celebratory bark, 7-year-old Kelso bested about 225 other dogs — including another shown by his college-student owner — to take the overall championship. And Roo! made it to the final five to garner a prize for the top mixed-breed, or “all-American” dog.

The competition put a fast- growing canine activity on U.S. dogdom’s biggest stage, with the finals nationally televised on Fox Sports 1. While Kelso has won other agility titles, the Westminster trial was something special to his owner, Delaney Ratner, of Cape Elizabeth.

“It’s an awesome way to get our sport out there,” said Ratner, a sophomore economics major at the University of Massachusetts at Amherst. The daughter of agility trainer Cindy Ratner, she could hardly decide which dog to root for in the final five — Jonesy, a miniature schnauzer she co-owners with her mom, won his height class.

A papillon named EZ, shown by John York of Royal Palm Beach, Fla., and a Pyrenean shepherd called Dash, owned by Ashley Deacon of Menlo Park, Calif., rounded out the finalists.