Animals have a soul, which many people do not realize.
The soul is composed of 3 elements: a MIND to think, a Heart to feel emotions, and a WILL to decide. Animals, just as humans, posses these characteristics.

Animals can become sad, and depressed, if mistreated. Likewise, animals are happy and content when we respect them as creatures of God's divine handiwork and omnipotence. Animals do not have a sin-nature, as humans do.