The Australian Stumpy Tail Cattle Dog is not an Australian Cattle Dog with a docked tail. They are naturally bob-tailed breed and stands square with plenty of leg length under the body.
There are major structural differences in breed type between the two breeds of Cattle Dogs. Stumpy Tail Cattle Dogs are a natural bob-tail breed. Some Stumpy Tail pups are born with long tails and should not be discarded from a breeding program if they are of structural quality, and bred back to quality natural bob tails.