New Zoo Guide, August 31, 2011!

Zoo: Breed even more animals now!

Source: Official Farmville Blog!

The Zoo is now available to breed more animals in FarmVille! Harvesting the animals inside the Zoo counts towards Animal Mastery! And guess what? More animals in your Zoo means more chances of finding new Animal Mystery Babies! Build your Zoo and start growing these cute little animals today!
The Zoo is the third of seven total new breeding buildings to be released.

Farmers with an Animal Trough will receive a message to replace it with a new Zoo, Pet Run or Wildlife Habitat. But do not fear, the Zoo, the Pet Run, Wildlife Habitat, and other forthcoming breeding pens will offer you even more opportunities to claim Animals!