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Friday, June 10, 2011

Miniature Schnauzer Breed Origin Canada Health and DNA

The entirety of the Miniature Schnauzer breed is founded on three sires born at around the turn of the last century. Ours is a "man-made" breed, created by German breeders who sought a miniaturized version of the Standard Schnauzer. The first twenty years of development were a period of intense inbreeding, during which time size and type were established. The gene pool, already very narrow, suffered a severe bottlenecking event in the 1940's when a single American sire gained prominence. By the time of his death in 1959, his sons had replaced nearly all other sire lines. As a result, all Miniature Schnauzers alive today trace their ancestry tens of thousands of times over to this one dog.

 To complicate matters, approximately 75% of all female lines descend from a single imported bitch, Ch. Amsel VD Cyriaksburg. Thus, despite their high numbers, the Miniature Schnauzer is one of the most homozygous of breeds at the genetic level - a fact predicted by the historical record and confirmed by those who have conducted DNA research into health defects in this breed.

In North America the Miniature Schnauzer competes in the terrier group in which small, neatly carried ears and straight tails are a competitive norm (for comparative examples see Airedales, Fox Terriers). Never in the history of the Miniature Schnauzer has selection for length or shape of tail been practiced. From the breeders inception, ears have been cropped and tails docked at approximately two vertebrae, with carriage very high on the croup favourite. Therefore, the unlocked tail often curls forward and down over the flank - a highly undesirable trait in the arena in which our breed competes. Nor has there been selection for any specific type of ear type or carriage. While a few dogs compete successfully with drop ears in North America each year, the vast majority are cropped.

Early evidence coming out of Europe suggests such individuals are quite likely the minority
The Miniature Schnauzer Club of Canada is concerned that any enforced ban on these procedures will
rapidly swing selection pressure towards the sires and family lines that produce the newly desired traits,
while lines that do not die out.

Miniature Schnauzer

The phenomenon is already underway in Europe, the UK, and elsewhere, as breeders are actively
seeking out and promoting the minority of sires with straight tails. (While corrective practices common in other terriers - ear "banging", skin tucks, and nicking of tail tendons - may mitigate selection pressure to an extent, we would prefer to prevent their expansion into our breed.) In short, the "unintended consequence" of forcing new and much narrower selection practices for both ear and tail conformation has the potential to reduce the genetic diversity of a gene pool in which full inbreeding coefficients already exceed 40%.

The increase in genetic disease frequency that can result from rapid swings in selection practices is a well documented phenomenon. Indeed, it is one of the primary risks that breed clubs are cautioned about when new DNA tests become available. Removing a large number of animals from a finite breeding population for whatever reason - can carry serious risk to long term breed health.

Miniature Schnauzer
This risk is one that we do not wish our breed subjected to. Thus, for the Miniature Schnauzer breed, the debate over docking and cropping is not merely a question of whether or not cosmetic surgery is "necessary" from the standpoint of the individual animal; it's one that holds serious and irreversible implications for our breeders genetic diversity and disease rates. The Miniature Schnauzer Club of Canada urges veterinarians and legislators alike to thoroughly investigate and consider all of the implications their decisions may have for the future our breed and others before supporting such initiatives.

Tags: Miniature Schnauzer, Miniature Schnauzer Breed Origin Canada Health and DNA, Miniature Schnauzer Club of Canada, Miniature Schnauzer Care and Breeders

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