If memory serves, the story goes that the soviets trained their dogs with soviet tanks - so when they released the dogs into battle, they turned around and ran for their own tanks.
Possibly apocryphal, but quite funny.
It wasn't so much about the design of the tank as I recall. Instead it was about one side using diesel tanks, with the other side using gasoline in their tanks. The dogs turned out to be trained on the smell of the fuel, which caused them to be attracted to the wrong vehicles.