Why Does My Dog Keep Licking My Other Dogs Back. 2 things to consider about your dog licking your other dog’s back. Hot spots themselves can lead to the introduction of fungus or bacteria, causing a secondary infection that may spread from the original site and even become systemic.
If this is something that’s been going on for some time with no detectable health issues involved, there’s probably nothing to worry about. The jaw shuddering is the flehmen response. Some dogs have behaved like that, smelling cancer, in humans.