PCD

Primary Ciliary Dyskinesia (PCD)

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Primary Ciliary Dyskinesia (PCD) is a hereditary disorder affecting the cilia, the microscopic hair-like structures lining the respiratory tract, brain ventricles, and reproductive organs. In Old English Sheepdogs, PCD disrupts the normal functioning of cilia, leading to a range of health issues. This condition is inherited in an autosomal recessive manner, meaning both parents must carry the defective gene for an offspring to be affected.

Fortunately, DNA testing is readily available for PCD in Old English Sheepdogs. This test helps breeders identify carriers and affected dogs:

  • Free (+/+): The dog is clear of PCD and does not carry the gene.
  • Carrier (+/-): The dog carries one copy of the PCD gene but is healthy.
  • Affected (-/-): The dog has two copies of the PCD gene and has the disease.

PCD primarily impacts the respiratory system, resulting in chronic respiratory infections. Symptoms often appear early, typically within the first few weeks to months of a puppy’s life. Common signs include persistent coughing, sneezing, nasal discharge, and recurrent respiratory infections such as sinusitis, bronchitis, and pneumonia. Male dogs with PCD are often sterile due to immobile sperm. Additionally, some affected dogs exhibit situs inversus, a condition where internal organs are mirrored from their normal positions, though this does not usually cause clinical issues

There is no standardized grading system for PCD.

PCD in Old English Sheepdogs follows an autosomal recessive inheritance pattern. Both parents must be carriers of the defective gene to produce affected offspring. Genetic testing can identify carriers, who, while not showing symptoms, can pass the gene to their offspring. When two carriers are bred, there is a 25% chance of an offspring being affected by PCD, a 50% chance of being a carrier, and a 25% chance of being unaffected.

To prevent PCD in Old English Sheepdogs, it is crucial to genetically test breeding dogs. Only breed carriers to dogs that are clear of the mutation and do not breed affected dogs. This approach helps reduce the incidence of PCD in future generations.

The prognosis for dogs with PCD varies. While the condition is not curable, many dogs can live for several years with proper management of their symptoms. Regular monitoring and treatment of respiratory infections are crucial. However, the condition tends to worsen over time, and the response to treatment may diminish. Early diagnosis and appropriate care can significantly improve the quality of life for affected dogs​. However dogs with severe PCD might experience frequent infections and have a shorter lifespan.