Are there prosthetic tails for dogs?

I think you may just be dealing with a dog that hasn't been properly socialized. Australian shepherds are bred and given docked tails, that is what the breeds specifications are. Not to mention there are lots of dogs that don't have tails (ie:Rottweilers, Dobermans, er Spaniels, etc) and generally speaking issues with other dogs hasn't been attributed to having no tail. I know this isn't answering your questions and I apologize for that... I have just never heard of this before. I am interested to see what other people know about it.