I never said you couldn't "improve the line"--which at this point would be to one's own individual preferences, not to a "standard." But you would not be "inproving the breed" as the color variation does not meet the definition of the breed...at least not yet. :)

I think the first line of your statement about sums it up. You have not seen any scientific studies!!! Neither has anybody else. I have not seen the studies on the blues either. In fact the only source I can find is this same website that is stating oppinions as facts. You say these studies on blues do exist so can you please provide a link. I am always interested in learning more and since my primary goal is to eliminate genetic defects it is very important to know where these studies are so I can read them.
I have a friend who breeds blue shar pei and the same thing was said about them. 15 years of breeding them shows that they do not have any problems.


I have one other question for the OP. You started this post saying you wanted to learn and you now state your last posts as fact. Why did you make this post if you had already decided you knew all the facts? I was under the understanding that this was to learn more about breeding and improving the breed?

What about the part after the first line? Again...how's anyone to know it is just because there has not been ample time to conduct long term studies on the theory? Time will tell. IF there is an underlying problem, it will show itself at some point. I think it's safe to say that it has yet to be proven one way or the other.

Sure thing. Give me time to find it. I know there was an article about it in a magazine I have somewhere too...I'll have to dig through a closet to try to find it. It never hurts to get all the information possibly available. I remember a while back there was a member here that had a blue born that had lots of info, but I can't remember who it was. :(


She also said that she was interested for purposes of wanting to SHOW Yorkie in conformation events--so I was under the impression that was the kind of information she was looking for, which does not pertain to non-standard colored dogs. (Since they can't be shown at this time.) So I guess really the same question could be asked of you...info on Partis really seems kind of irrelevant to the info she was looking for. At least until they can be shown too. :)

Here ya go...I believe that I only provided those written by vets and from the Journal of Veterinary Science, so hopefully these will serve their purpose as the "facts" that you are looking for. (You probably won't find much unless you are searching by the scientific name of the condition, 'blue born' is more of a slang term.) Let me know if you need more...:) I will *try* to find the magazine article this weekend.

Journal of Veterinary Science

IGCA : CDA

Color Dilution Alopecia

http://homepage.usask.ca/~schmutz/do...tions.html#CDA

- DPCA Breeders Education

Excellent post :thumbup::thumbup:. I do want to know after reading this has anybody had problems with hair loss on their standard blue and tan colored yorkies? I did not know this was a problem before but the articles do state that the darker steel blues do not seem to have the problem. Let me also post a quote from one of the excellent articles you provided.

" Deeply pigmented or white areas of coat are unaffected. In blue dogs with tan points (Yorkies and Dobermans) the tan areas retain a normal appearance. In piebald (white spotted) individuals, the white areas are unaffected by the hair loss."

Of course those areas are not affected...the condition is one that is unique to the "blue born" dogs. :confused: The darker steel blues to not have the problem because they are not "blue born" dogs...I think maybe you are confusing "blue borns" and the steel blue standard coat--they are not one and the same. Clearly the white and tan points would not be an "affected" area. In the quote you provided, the "pie-bald" dogs they are referring to are not even Yorkies...they are OTHER breeds.

Some defects with colors:

http://www.lsu.edu/deafness/VetJDeaf2004.pdf
http://www.ivis.org/advances/Vite/braund20b/ivis.pdf

Color dilution alopecia... for odd colored
Canine non-inflammatory alopecia: What's new and what's old - - DVM

McGreevy also highlights one example of the effect breed standards can have on the physical form of a dog.
“In some cases, traits that are better regarded as defects have actually been included in breed standards,” he said. “For example, brachiocephaly (a skull abnormality which can lead to respiratory problems) is prompted by the standard for the Boston Terrier (American Kennel Club 1990: FCI Standard No140) that requires an animal to be ‘short headed’ and possess a ‘square head and jaw’ with a muzzle that ‘is short, square, wide and deep … shorter in length than in depth; not exceeding in length approximately one-third of the length of the skull'.”

There have also been findings into coat colour and the possibility that some pigments are linked with aggression and other problems.

“There is definitely an association between pigmentation and neurological defects, such as deafness and eye disorders in merle dogs, in which both homozygotes and heterozygotes are affected (Klinckmann et al 1986). Breeding for hypo-pigmentation is a questionable strategy,” he said.

Sadly, it seems the more we continue to breed for aesthetic and superficial qualities, the greater the risk our canine companions face of suffering from health and behavioural problems.

The problems with limited gene pools have also been well documented and studies have shown that even the best-bred dogs still carry at least one deleterious recessive gene.
from The Great Debate - Designer Dogs Dog Breeding - Dogs Life Articles - Dog Information - Dog Breeders - Dog Training



I know they aren't enough and it's way past my bed time :) I think vets in universities are more knowledgeable about up to date journals and studies.

You may also read the books mentioned in the Goldenray site.

First I want to thank you again for finally providing some scientific evidence on here. I especially like that you provided scientific evidence that Piebald or white Yorkies do not share this problem. I went to my myspace page and looked and I actually do know someone with a standard blue and tan yorkie that lost all it's coat. I just thought her dog had something happen to it. How big of a problem is this? Has anybody on here had this happen to their yorkie?

I also reread the original post and I can not find anything about her wanting to breed for the show ring. It says something about loving the show ring and not being able to join.

Of course they don't "share this problem." How on Earth could they? The "problem" is blue born dogs--of course a piebald Yorkie wouldn't share it--otherwise it would BE blue/gray! The piebald dogs mentioned and tested were NOT Yorkies. I'm not sure how or where you are drawing that conclusion from. It's not something that just 'happens' to Yorkies as older adults, it's a condition they are born with. I'm sorry, not trying to argue, but your statment does not make sense. :confused: Again, I think maybe there is some confusion between a "blue born" dog and a dog with a steel blue coat... I thing maybe I am misunderstanding what you are trying to say.

It's EXACTLY what her post said...she loves the show ring and can't wait to join. Clearly that is what her goal is.

Thank you for posting this. It looks like they were mostly focusing on other breeds. It does seem blue is something to avoid. I have never seen blue eyes in a yorkie before.

They do not mention blue born yorkies in this artical. They mention yorkies and state that the tan area is not affected. I have actually seen this on a standard color yorkie before but did not know that it was a genetic problem.

Thanks BamaFan for answering in my behalf. My world is kinda slowing down at this moment. I am now prepping my puppy, which I am hoping to turn out worthy to be shown. :)

Golden Parti
I'm quite sleepy and still tried to find some. :) I just hope one day that there are more means in health screening of breeds. Then color won't be an issue especially when it's already easy to prove that they are Yorkies and very healthy and free of genetic problems. I did dream of Biewers way back.

As of the moment, I think the recessive genes poppin out might bring out something more serious. Being yorkies, off colored ones are already carrying the problems of the standard yorkies and striving to breed for colors is a bigger gamble.

There are also various types of alopecia. Some hereditary, some not.

It's time for me to sleep.

Let's keep the thread cool :)

What article are you referring to? I thought you were claiming that an article stated that Piebald/White Yorkies are not affected by this disorder--are you referring to a different article/point now?

The tan area is not affected because it is TAN. It is not possible to see THIS condition on a standard colored Yorkie--if the Yorkie has this condition, then it is not standard colored--one of the characteristics of the condition is the discoloration of the 'blue' color--a Yorkie would not be standard colored if it's pigmentation was discolored.

There are other disorders though (such as Demodex) that are different altogether than could cause similar results. Maybe that is what you saw?

Joining the show ring is not breeding for the show ring. If she has a really nice standard yorkie she can join and never breed her dog.

Opps, I missed this the first time.

Yorkshire Terriers.((2),(3),(4),(5)) Dilute individuals carry a recessive genotype of dd and are characterized by blue, bluish-grey, lavender or flesh-colored noses, lips and eye rims. The coat colors may include blue, fawn, blue-fawn, bronze, taupe or some variation of these. These dogs are usually easily distinguished from their deeply (non-dilute) pigmented counterparts. Deeply pigmented individuals carry a dominant genotype of Dd or DD and have black or liver noses, lips and eye rims. Coat colors may include black, red, red-fawn, liver or variations thereof.

I definately don't want one of those. Somebody is trying to sell a litter of them on puppyfind.

This is what I was referring to.

CDA is characterized by loss of hair from dilutely pigmented areas. Coats are normal at birth, and onset of hair loss usually begins between six months and three years of age. Hair loss usually begins along the dorsal midline (middle of the back) and often spares the head, tail and limbs. The pattern seems to vary from breed to breed. It has been suggested(6) that darker colored (steel blue) individuals are less likely to be affected, may be less severely affected or may start to lose hair later in life than lighter colored dogs. This suggests that the severity of the disease may be related to the amount of dilution present. Deeply pigmented or white areas of coat are unaffected. In blue dogs with tan points (Yorkies and Dobermans) the tan areas retain a normal appearance. In piebald (white spotted) individuals, the white areas are unaffected by the hair loss. The hair loss may be total or partial and any remaining hairs are usually sparse, rough and easily broken or removed. The skin in the affected areas is usually scaly and may occasionally develop bacterial infections. Pruritus (itching) is usually absent, unless a bacterial infection has set in.

Why in some dilute dogs the macromelanosomes are clumped and in others they are not, is an interesting question at this time. The relationship between dilute pigment and hair loss is clear, but why are some dilute individuals unaffected? Weimeraners as a breed are dd, all individuals are dilute, yet the disease is unreported in this breed. In Dobermans, the dilute individuals comprise only 8-9% of the breed, yet 50-80%6 of the dilute dogs have CDA. In Italian Greyhounds, many individuals are dilutes, yet the IGCA health survey reported only 71 affected individuals among the approximately 2200 dogs included in the survey.(7) If half the dogs included in the survey were dilutes, the incidence of CDA in IG's would be around 7% of the dilute population, as opposed to the 50-80% affected dilute Dobermans.

A third allele (dl) which is associated with CDA has been proposed.6 While this is a long way from being proven, it could help explain why some dilute animals are unaffected. Dogs with a genotype dd would be normal coated dilutes, ddl would be intermediates (mildly affected?) and dldl would be CDA affected. A genotype of Ddl should represent deeply pigmented dogs which were carriers of CDA.

Italian Greyhounds would be an interesting breed to study regarding the heredity of this condition. IG's have a relatively high incidence of dilutes, and a relatively low incidence of CDA affected dogs.

I think it was pretty obvious to most by her post that 1) she is planning on breeding in the future and 2) she is wanting to show. And as she has already stated in several other post, she is interested and supportive of standard colored dogs as defined by the YTCA. Really, what is the point of this misunderstanding?

In blue dogs with tan points (Yorkies and Dobermans) the tan areas retain a normal appearance. In piebald (white spotted) individuals, the white areas are unaffected by the hair loss. [/QUOTE]

Ok, I thought that this was the portion you were referring to.:thumbup:
-Yes, the tan area is not affected--the disorder, by definition does not affect tan.
-The dogs that were tested were NOT Parti Yorkies. They were more than likely other breeds with a standard that calls for a tri-colored coat. Meaning that there were generations and generation of dogs that probably NEVER possess the genetics for a blue/tan coat. However, Parti Yorkies do. So testing a breed that is piebald by standard/history is not going to draw results that can neccessarily be applied to Parti Yorkies.
-Parti Yorkies are not going to be affected by this because again, it affects blue coat and they don't have a blue coat.
-There is no evidence in THIS article that Parti Yorkies cannot pass on the disorder to offspring IF they are still carrying the genes for the standard colored coat.