If you’ve vaccinated your cat, or treated your dog for fleas, chances are you’re familiar with one of the newcomers to this year’s Fortune 500. Coming in at number 400-87, Zoetis (zoh-EH-tis) is a global leader in the animal-health sector. Its drugs and vaccines are used by both veterinarians and farmers. Zoetis has only been a stand-alone company since 20-13. It was spun off from pharma giant Pfizer in an I-P-O that raised two-point-two billion.