To wine and dine Sasha, a 450-pound Siberian tiger at the Bronx Zoo, try serving beef and rabbit. To lure him for a snack, whip out the frozen treats his zookeepers call "bloodcicles." But to really get his olfactory engines running, you need the secret weapon: Calvin Klein's Obsession for Men.

Zoos have long spritzed perfumes and colognes on rocks, trees and toys in an effort to keep confined animals curious.

In...