The poster with the big red heart is what I'd term a Judas Goat....

The poster with the big red heart is what I'd term a Judas Goat.

A Judas goat is a trained goat used at a slaughterhouse and in general animal herding, especially sheep. The Judas goat is trained to associate with sheep or cattle, leading them to a specific destination. In stockyards, a Judas goat will lead sheep to slaughter, while its own life is spared. Judas goats are also used to lead other animals to specific pens and on to trucks. "Yes follow the judas goat to your death"

http://soonerthanlater.hubpages.com/hub/Judas-Goat