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Juvenile Dilated Cardiomyopathy

Juvenile Dilated Cardiomyopathy (JDCM) is an inherited fatal disease in young Portuguese Water Dogs that is caused by a recessive gene (both parents of a puppy must carry the gene to produce the defect). Puppies affected with JDCM die suddenly or with very little warning usually between the ages of six weeks to seven months old. There have, however, been cases reported younger than six weeks as well as older than seven months. The signs and symptoms of JDCM include a 12 to 48 hour onset of loss of appetite, decreased energy level, vomiting, and difficulty breathing. Some pups have no physical signs or symptoms at all, may just collapse and die, or are found dead by the breeder or new owner. At this time, there is no known cure or treatment but there is a way to prevent producing JDCM affected puppies.

We now have a DNA gene based test, based on a cheek swab or a blood sample, which will determine if a dog is Normal (not carrying the gene) or is a Carrier of the JDCM gene. All breeding animals can be tested to determine their status, thus avoiding the breeding of two JDCM carriers and producing puppies which will die of this deadly disease.

Researchers at the University of Pennsylvania have recently developed this DNA test for detecting dogs who do not have the JDCM gene and dogs who are carriers of the JDCM gene. Breeders are now able to have their breeding animals tested for Normal or Carrier status. Never breed two carriers together or you will produce puppies which will die.

 Dogs used for breeding should be DNA tested for JDCM status and that one of a breeding pair, either the sire or the dam, be tested as Normal.

It is important that all prospective puppy buyers discuss Juvenile Dilated Cardiomyopathy with breeders. Ask if the parents have been tested for JDCM and what their status is, Normal or Carrier. A puppy from a JDCM DNA tested Normal sire or dam will not be affected with this fatal disease.

More information can be found from the link below


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