I have a 3 year old westie who developed CMO at age 3 months old. It hasnt progressed too far (luckily for Mack). Has anyone had experience of this and whether it is rare or common, and whether it is hereditary or not? I look forward to hearing your replies. Thanks

One of my friends had this in his WHWT puppy. It is not very common and is thought to be hereditary. The prognosis is very good and I have been told that most puppies grow out of it at about 12 months of age (my friend's did).
The pain was controlled by pain-killers when required, which in my friends dog was not all the time.

Snomaes

thanks for your comments - I find it interesting to learn from this site that it is not common. Hope your friend's westie is happy and well now. Gillie xx

Hi Gillie,

It is not that common, more common I am afraid in the pet market breeders as they don't really know enough about their lines hopefully the show type breeder does.

It is a resessive gene ( ie both parents must be carriers not just affected with it). Which is one of the problems in identifying carriers, a dog can be a carrier (showing no symptoms)  but them produce a litter affected with it.

For example if you had a popular stud dog that was used 7 times at stud all puppies seemed fine then on the 8th time used you had a litter of affected puppies.  This would tell you the stud dog was a carrier and also the bitch.  The 7 litters before would probably produce carriers even though nothing was visible.  Hopefully the parties would contact everyone from previous matings and puppy owners to tell them of the problem and remove ALL of them from the breeding programs.

Hope that makes sense.

Having re-read your post you are quite right that once identified all affected dog owners should act. Unfortunately when I contacted the breeder of my westie, he did not even bother to reply. I can only assume that mack's 2 sisters and brother carry the gene and if their owners dont know they could have been mated with other westies by now (they are nearly 4 years old). It is a sad situation.

thanks for everyone's replies. It is very interesting to hear other's knowledge!

gillie x