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PKD is polycystic kidney disease. This is a genetic disease where cysts form on the kidneys, eventually producing loss of effective renal (kidney) function. Cats diagnosed with PKD can live many years, or die quickly.

For many years feline PKD was believed to be a disease of Persian cats and cat breeds such as Ragdoll, Himalyan, Neva and other purebreeds created from Persians. Breeders with other breeds were not worried about PKD - it was a disease rarely seen.

Then the gene testing for one version of  the Persian PKD gene (PKD 1) was developed. The testing was inexpensive compared to diagnostic sonographing by a Board Certified Veterinary Internist, and breeders jumped at the chance to have the genetic testing conducted.

It was poorly understood that the PKD 1 test *only* indicated whether or not a cat had ONE of the several Persian forms of PKD. Testing negative for this PKD 1 gene mutation - even for Persians and Persian X's - only meant the feline was not effected by that *single* PKD genetic mutation. It was not diagnostic.

Unfortunately, many catteries tested genetically (@40 USD per gene test, compared to 450 - 650 USD for a echosonograph), and began declaring they were PKD free catteries...

The only predictive and accurate test for PKD in cats is via echosonograph conducted by an Board Certified Veterinary Internist with high resolution equipment.  How accurate is such testing? The Journal of Feline Medicine and Surgery found in a 2009 research study (abstract below), that the results from testing peformed as above are 100% repeatable. That's pretty definitive!!

Evaluation of the repeatability of ultrasound scanning for detection of feline polycystic kidney disease.

Wills SJ, Barrett EL, Barr FJ, Bradley KJ, Helps CR, Cannon MJ, Gruffydd-Jones TJ.SourceSchool of Clinical Veterinary Science, University of Bristol, Langford House, Langford, Bristol, BS40 5DU, UK. sheila.wills@aht.org.uk

Abstract 

Polycystic kidney disease (PKD) is the most prevalent inherited genetic disease in cats with Persian and Persian-related breeds predominantly affected. Diagnosis of PKD relied on ultrasound scanning until the recent development of the PKD gene test.

However, gene testing has limitations as it will only identify the autosomal dominant form of PKD (PKD1 - Persian PKD) and not other forms of cystic kidney disease.

Ultrasound scanning also has the advantage of being able to assess the severity and progression of disease in PKD affected cats. The aim of this study was to demonstrate the repeatability of ultrasound scanning in the detection of PKD and to assess progression of the disease over time.

This study demonstrated 100% repeatability of ultrasound scanning in the detection of PKD and has also demonstrated progression of disease in 75% of PKD positive cats assessed over a 1-year period.

J Feline Med Surg. 2009 Dec;11(12):993-6. doi: 10.1016/j.jfms.2009.07.002. Epub 2009 Aug 5.

Zhelan Manchzhury turned three years old on 27 January 2013! Happy Birthday, Zhelan!

Zhelan is a terrific asset to the Siberian breed. Zhelan is the very first Manchzhury Siberian placed anywhere in the world except for Russia and Finland!!

Discover Zhelan's low level of inbreeding, pedigree, and enjoy his stunning photos

by checking in with Zhelan  on his page.

PKD = polycystic kidney disease. Cats can inherit it, people can inherit it. If a cat's parent has PKD, that cat has a 50% chance of having inherited the gene and later expressing the disease.

This information sheet on Polycystic Kidney Disease from FAB (the Feline Advisory Bureau in the UK), clearly explains about the disease. Read the full sheet at the link shared below.

What is polycystic kidney disease?

Autosomal dominant polycystic kidney disease (AD-PKD) is aninherited condition that causes multiple cysts (pockets of fluid) to form inthe kidneys. These cysts are present from birth. They start out very small but they grow larger with time and may eventually severely disrupt the kidney; when that happens the kidney can no longer work and kidney failure develops. The cysts usually grow quite slowly, so most affected cats will not show any signs of kidney disease until relatively late in life, typically at around seven or eight years old, or even into older age. However, in some cats kidney failure will occur at a much younger age and at the moment there is no way of predicting how rapidly the disease will progress in any particular cat.

 This is a cat diagnosed with PKD receiving supplementary hydration.

How common is PKD in cats?  

Unfortunately AD-PKD has now become very common in some cat breeds. Persians and Exotic Shorthairs have the highest incidence of problems ... Other cat breeds that have been developed using Persian bloodlines, and ... may also have a proportion of affected cats.  In unrelated (cat) breeds (PKD) is an extremely rare condition....

How is PKD inherited?

AD-PKD is the result of a single, autosomal, dominant gene abnormality. This means that:-

 Every cat with the abnormal gene will have AD-PKD; there are no unaffected carriers of the gene.

Every cat with AD-PKD will have (an) abnormal gene, even if that cat only has a few small cysts in its kidneys.

A cat only needs one of its parents to be affected with AD-PKD in order to inherit the abnormal gene.

Every breeding cat with AD-PKD (risks passing on) the disease on to its kittens, even if it is mated with an unaffected cat....

How can I find out if my cat is affected?

ForestWind Siberians note: The information presented by FAB about finding out if your cat is affected is obsolete. At the time this article was written - 2008 - it was thought all cats with PKD had the very same PKD mutation. Since then, several genetic mutations in the Persian breed alone have been identified. Gene testing only identifies one of those Persian genes. The other mutations - whether Persian or  in non related breeds - are not identifiable by genetic testing. The Gold Standard (or should we say Platinum Standard?!) in testing remains the echosonograph administered by an experienced Board Certified Veterinary Internist. Testing administered by a Vet Tech, small animal practice Veterinarian or non board certified internist, or an inexperiened sonographer is not reliable.

Read the entire original article at the link below. Please note the article is five years old and information such as about genetic testing is obsolete. Unfortunately, there are many breeders and even Veterinarians who do not stay current with research and those persons beleive that gene testing for the one Persian gene is an accurate assessment for their cat's diagnosis. Remember - the only accurate PKD diagnosis is from an echosonograph administered by an experienced Board Certified Veterinary Internist!

©This information sheet is produced by the Feline AdvisoryBureau

As a prospective ForestWind Kitten Family Member, it is important for you to know the steps we take to keep our cats and kittens healthy and vibrant.

1. Our Siberians are scanned by Board Certified Specialists every two years for HCM. Even in breeds with identified HCM mutations, regular ultrasonography is necessary to rule out development of HCM.
2. We belong to several breeder groups that follow HCM research as well as Siberian breed specific groups that promote openness in sharing information about affected cats.
3. We follow an extremely aggressive policy on HCM in our lines. If we learn that grandparents, parents, aunts and uncles, siblings, or cousins of our cats have been affected with or have produced offspring with HCM, we remove all related cats from our breeding program.  
4. We helped fund Dr. Kate Muers’ 2008 HCM study at University of Washington. Unfortunately, the study did not yield identification of an HCM gene in Siberians. Research has since continued at University of California, Davis.
5.  We contribute monthly to a WINN Foundation fund for HCM research in Siberians.
6. We select our breeding cats to have COI of 5% or lower, and aim for litters with COIs of 0%.

While placing genetic diversity above visual conformity results in a slower trip to "Winner's Circle,"  it also protects the entire Siberian breed for many generations to come.

We practice what we believe: that Siberian health and temperament should be the number one priorities of any ethical Siberian Cat Breeder.

Click here to learn more about HCM symptoms, diagnosis, and treatment.

One of the adoption questions we are asked a lot is about predicting allergy levels  in Siberian cats. Folks would like to know if there is any relationship between coat color and allergen level. The short answer is "no." Folks would like to know if there is any relationship between sex and allergen level. The short answer is "sort of." Folks would like to know if there is any way to predict allergen level in a litter if both Siberian parents are tested low allergen. The short answer is "statistically, yes; for a given, kitten, no"

So, let's talk more about allergen levels in Siberian cats. First, it is important to remember that there is actual published research that documents that some Siberian cats inherit one of a few mutations that results in a lower production of fel d 1, the protein all cats make that some people are allergic to.This research was conducted at University of California Davis Veterinary School by Dr Leslie Lyons.

Second, it is also important to note that not one other breed of cat,  including domestic cats ("moggies"), have the genetic mutation that some Siberians have that results in a lower level of fel d 1 production. Not sphynxes, not rexes, not ragdolls, not any of the breeds that some breeders claim are "hypoallergenic." Not one breed other than the Siberian Cat.

Now that we know there is a scientific basis for some Siberian cats to cause little  or no allergic reactions in some people, let's look at other research that purported to connect a cat trait to lower (or higher) allergen levels.The biggy is coat colour.

At least weekly we get questions about coat colour and allegen levels: "We read that white cats have lower (higher) levels of fel d 1." "We read that dark cats have lower (higher) levels of fel d 1." "What colour cat has the lowest level allergen?"

Unfortunately there is no good science to indicate any correlation between coat color and allergen production level in any cats.

No, light colored cats are not less allergenic.

No, dark colored cats are not less allergenic.

No, silver cats are not more allergenic.

No, black cats are not more allergenic.

Causing this confusion are two situations. One is a set of now debunked research claiming a connections between coat colour and allergen level. The first is a much quoted (and very wrong) study that: light coloured cats were less allergenic AND a second study that indicated that dark coloured cats were less allergenic.

Both of these studies researched allergen levels in mixed breed (stray / domestic) cats. None of the cats tested had genetic mutations (like about 50- 60 % of the Siberians do), resulting in a  lower production of fel d 1 for those cats. However, all cats have differing levels of fel d 1 production, and these different levels also carry according to time of year, diet, and sexual maturation of the cat.

The other contributing confusion to the coat colour and allergen level association is that light haired cats who are related to the Siamese tend to have higher allergen levels, as the Siamese breed over all does. The Siamese cats have a light coat, as do many of the breeds derived from them, so the light colour became associated with a higher allergen level. This can be seen in the Neva - or "colourpointed Siberian" who was created by planned matings between the original Siberians and both Ragdolls (a Siamese x breed) and Himalyans (another Siamese x breed). Until there were enough matings between the breeds to pass on the Siberian low allergen mutations, Neva cats tended to be high allergen.

Like coat color, there is no connection between the Siberian cat's genetic mutation and sex of the cat. With regular domestic cats, a male cat who is not desexed typically produces top levels of allergen, while a desexed female typically produces the least amount allergen.

Before laboratory testing for fel d 1 level became available, we woudl recommend females be adopted to allergic and asthmatic families based on the odds of a desexed female having a lower allergen level than a desexed male. Now that the research has been done at University of California Davis Veterinary School, we know that the lower alelrgen production in some Siberian cats is caused by one of several possible genetic mutations (there are severalin the Siberian breed) and furthermore that the protein production levels are individual to each cat - not related to the sex of the cat.

While allergen level testing is now available for Siberian kittens, it is extremely expensive and the kittens must wait to be adopted until they are older.  ForestWind does provide this option to adoptive families, but most of our families decide to adopt successfully by implementing several of the anti-allergy, anti-asthma strategies we recommend - from air filtration to bathing to feeding guidelines. To date, we have only rehomed three our of Siberians due to allergies. The most recent rehoming was this winter, 2012, and in that situation a family member became cat allergic several years after adopting, and no one had been allergic prior to the adoption taking place.

As a cat allergic and asthmatic family ourselves, we are well aware of the needs and interests of the allergic family and work closely with you to ensure your successful adoption.