just to add a little note about dogs with the tip of there tails bleeding.
when i have had this happen to my dogs in the past,
i cover in vet powder and put a hair curler on the end of the tail, it keeps the fresh air around the wound,and protects any blows
this would be better practice than the hose pipe method.
it can sometimes be impossible to heal this up. even after many weeks later, it can open up again,
be warned.
the vets are always the best option.