You can see all the champions on the World Dairy Expo website.

Here’s the Junior Supreme Champions though.

SMART REMAKE ENCHANTMENT (Jersey)
Exhibited by Craig A. Martin of Olivet, Michigan
Production: 2-11 288d 18,488 4.5% 835F 3.4% 629P

World Dairy Expo Junior Show Reserve Supreme Champion
JOLEANNA WHITE RAIN -ET (Holstein)
Exhibited by Derek Johnson of Unadilla, New York
Production: 2-01 305d 19,297 3.5% 3.0%