The Australian Shepherd is noted as the very first bobbed tail breed.
In America Aussies natural state of orgin bobbing a tail was the safest thing to do. They are herding dogs and with a tail it would get in the way.
Docking is along the same lines as Bobbing. It is done for cosmetic purposes.
In the end the reason why they do this to the tails is to prevent injury to the tail while moving through thick brush. It could cause infection.
Some countries have banned bobbing tails saying "it is an unjustified mutilation of animals."
I personally don't see how when all the Bob does is protect the dog from necessary harm. It doesn't even hurt them, because when it is done they are to little to know what is going on.
