A partir d'un article américain "What is BSD and how is it spread in our dogs ?"

 

OK : représente un chien sain, non porteur de la maladie dans ses gènes.

"porteur" : représente un chien qui ne manifeste pas (encore) les symptômes de la maladie mais qui la porte dans ses gènes.

"atteint" : représente un chien qui a les signes extérieurs de la maladie.

Ce qui suit est le mode de transmission d'Alopécie X le plus plausible pour le moment, suite à des recherches et expériences de plusieurs éleveurs américains. Il y a encore des études qui se font (à Bern par ex), et ailleurs dans le monde, pour, entre autre, encore aprofondir les connaissances du mode de transmission d'Alopécie X, connu pour le moment :

 genetique alopecie1

genetique alopecie2

genetique alopecie3

genetique alopecie4

genetique alopecie5

genetique alopecie6

Comme vous pouvez le constater, la propagation d'une telle maladie peut être très rapide, surtout si les éleveurs cachent le fait que leur chien puisse être atteint. Nous avons besoin de vous pour receuillir des informations (confidentielles) et informer éleveurs et acquéreurs : n'hésitez pas à nous signaler le cas de votre chien

Article original :

What is BSD and how is it spread in our dogs ?

BSD is the acronym for Black Skin Disease it is also know as Alopecia and Severe Hair Loss (SHL) syndrome.  This condition or something similar is found in more of the Nordic breeds.  Visually (keep this word in mind as genetically it is different) it most generally occurs in males between the age of 18 months and 3 years.  There are many other conditions that can cause similar manifestations.  These might be hypothyroidism, Cushing’s and Addison’s disease, hormone imbalance, even parasites, which can all be tested for.  The key to a BSD diagnosis at this point in the game is to eliminate the other “like” conditions.  This means taking that dog to a dermatologist for some extensive tissue testing.

The term “black skin” is confusing as this is really only a symptom of the genetic condition, rather than the condition itself.  The coat loss allows exposure to the sun, which in turn will cause the skin to darken.  There are other symptoms that seem to go along with BSD, itching, joint problems, bone brittleness and others.  
 
From the information that has been tracked over the past few years BSD appears to be an X linked genetic issue.  What that means is that the condition is passed through the mothers who will (most likely) never show a sign of being a carrier.   A sire who has it can also affect his children.  At the bottom of this answer you will find a table that shows the genetic transference chart.  Certainly these are just theories at this point in time.  Until there is evidence otherwise this is the “trend” we have to go in.

 

 

DAM X SIRE = FEMALE OFFSPRING ARE MALES OFFSPRING ARE
OK Female bred to OK Male produce All OK Females All OK Males
Affected Female bred to OK Male produce All Carrier Females All Affected Males
Carrier Female bred to OK Male produce 50% risk of Carrier Females 50% risk of Affected or OK Males
OK Female bred to Affected Male produce All Carrier Females All OK Males
Affected Female bred to Affected Male produce All Affected Females All Affected Males
Carrier Female bred to Affected Male produce 50% risk of Affected or Carrier Females 50% risk of Affected or OK Males
Table from Ro-jan Poms and X linked inheritance pattern verified with passages found in 
Control of Canine Genetic Diseases (author, George A Padgett, DVM)


 
A breeder should have “at risk” dogs tested, including sending in tissue and blood samples to the Canine Genetic Diseases Network linked below.  A good breeder needs to understand their lines and to breed accordingly, not breeding the Affected Male, the less common Affected Female or the difficult to identify Carrier Female.  Understanding that the Female is the most dangerous as they never manifest the “visual” signs, they are the silent carrier.  If a Female has ever produced an affected dog they should be removed from the breeding program (evidenced in the chart below).  The problem here is that the Female has to produce it in a male offspring in order to identify if she is a carrier.  
 
Should you find out that a parent of your male is affected or a carrier, that male should be neutered between 4-6 months.  In the majority cases these boys have shown no manifestation of the condition.  The thought is that it might be the release of testosterone that occurs after that time and triggers the conditions visual affects.  If this actually  stops them from developing the condition or if they did not carry the condition remains to be proven.
 
Here are a couple of more links with more information on this condition:

 

BASIK

spitz adn

BASIK (Base Adn Santé Internationale du Keeshond), c'est l'application créée par Passion Spitz Loup pour vous donner accès aux informations relatives à la santé des lignées de spitz qui vous intéresse... Pour que vous ne puissiez plus dire "je ne savais pas !" Et parce que les éleveurs deviendront consciencieux si les acquéreurs le sont eux même : propriétaire ou futur propriétaire de spitz loup, c'est VOUS qui détenez l'avenir de la race au creux de vos mains !

Restons en contact !