Police say the muzzled dog — along with two other dogs and two cats — had been left in "deplorable conditions without proper care" in the parked truck.
They say the discovery came a week after someone complained to the London Humane Society about three dogs exposed to unsanitary conditions in a home.
It's alleged the residents of the home left with the dogs to avoid Humane Society officers.
Donna Hebert and Allan Folkins-Wyre were charged Thursday with counts of cruelty to animals.
The animals have been taken in by the Humane Society.