Years ago my brother and his roomate shared a house along with a boxer, a brittany and a cat. Every time the cat headed for the litter box the dogs would follow it and lay in wait while the cat did its business. As soon as the cat stepped one foot out of the litter box, they would both dart for the litter box and fight over the fresh cat droppings.

Epilogue:
Years later, the brittany was found 8 feet up a tree hanging from its collar and dead. Apparenty, the dog chased a critter (probably a raccoon) up a tree and when it slid back down the tree its collar got snagged on what was left of a broken off branch and hung itself.

The dogs name was Lucky. Irony? Lucky was easily the dumbest dog I ever encountered.