Petting Zoo Fence

This is a portable fence I spotted at a petting zoo in Burleson, Texas (USA).

Picture 1- Notice how the goats and pig roam freely around the pin. So calm and relaxed.

Picture 2- A herding dog approaches and reminds the goats who is in charge.

Picture 3- One of the goats snaps at the dog and pokes it with his horns. The dog retreats and growls, trying to regain control once again.