brookcove
Posted : 10/5/2006 11:07:54 AM
The bob-tailed characteristic is a dominant gene (I think) and is one of the ones that is dangerous in its homozygous form - ie, if you breed two bobtails together you have a risk of producing agenesis of the spine - no tailbone.
Thus, bob tailed breeds are usually artifically docked for the most part - any pup from these breeds has a 50% chance of being long tailed, 25% chance of being incompletely tailed, and 25% chance of being stumpy tailed (the old fashioned term for a natural dock).
Here's a fun website - Boxer people have probably seen this before. It covers the program of a man who was trying to introduce the natural bob tail gene from PWCs, into the Boxer gene pool, presumably to reduce the need for surgical docking.
http://www.boxerunderground.com/bu2000/aug2000/bobtail.htm