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Originally Posted by BamaFan121s  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.  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. |
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.