The rump is broad, strong, muscular and in proportion to the rest of the dog.
The female needs to have a wider rump than the male, because she needs to be able to comfortably pass puppies through her birth canal.
Its height should not exceed the height at the withers. The top line drops slightly towards the tail.
When looking from the side, the rump should be lower than the withers. If it is higher, it is usually due to inadequate angulation of the rear legs. If the topline is straight and the rump is at the right height, then the topline will slope slightly down towards the rump. Sometimes, dogs will have a dip behind the withers, which will create a topline that slopes up towards the rump, even if the rump is lower than the withers.
The croup is broad and flat to provide a fulcrum (axel) towards powerful reach of the hind legs.
The width of the croup is directly proportional to the amount of muscle that can be attached to it for the back legs. So, a wide croup can hold a lot more muscle than a narrow croup. Once again, the female should be wider than the male in this area.
The tail is thick and set fairly high. It should be well covered with hair and without kink.
Kinked tails are due to the vertebra in the tail fusing together. If you begin to breed a line of dogs with kinked tails, eventually the fusion of the vertebra moves up into the spine. This is very uncomfortable for the dog and eventually causes arthritis, which decreases the dog’s quality of life, and ultimately their life span. Fused spines will also effect movement.
Tails are traditionally docked but undocked tails are acceptable. Docking takes place at the 3rd or 4th caudal vertebrae.
The natural tail should reach approximately to the hocks when the dog is standing.
The natural, undocked, tail flows down and is relatively straight when viewed from behind.