Explain why a cow that touches an electric fence experiences a mild shock

The voltage exists between the fence and the ground.  The cow is grounded. The cow is touching the ground, completing the circuit of electricity. When the cow comes into contact with the fence, it becomes an electric ground which sends an electric current into the cow, through the cow, and into the ground. The pain experienced from the shock is due to the current that flows through the cow.

It may possibly be c i think |-/