A serious new genetic disorder has been found in the Cavalier King Charles Spaniel.

In Brief

MCADD: Medium-chain Acyl-CoA Dehydrogenase Deficiency in CavaliersThe affected CKCS nneds to breakdown certain fats quickly when their bodies run out of glucose, the stored fat which would normally be converted to energy cannot be produced quickly enough to meet the dog’s needs, which may cause them to suffer from low blood sugar, seizures, coma or sudden death.

More Information

MCADD: Medium-chain Acyl-CoA Dehydrogenase Deficiency

A recent study suggests that this genetic variant found in CKCS dogs could potentially trigger a condition similar to MCAD deficiency in humans.

MCAD is an enzyme found in coconut and palm kernel oils which is controlled by the ACADM gene. A protein-changing variant of the ACADM gene causes MCADD, a genetic disorder that prevents the dog’s body from converting certain fats to energy, particularly medium-chain fatty acids which leads to a build-up of metabolites that are toxic.

MCADD ExplainedAffected dogs cannot burn fat for energy when their bodies run out of glucose, and as a result they may suffer from low blood sugar, central nervous system dysfunctions, coma, or even sudden death. MCT oils, including coconut oil, should not be fed to any cavalier unless that dog first has been tested clear for the ACADM mutation causing the MCAD-deficiency. Avoid dog foods which have MCTs as their primary oils.

Symptoms to watch out for:

  • Seizures: Seizures or convulsions. If your CKCS experiences seizures, it’s important to consult a veterinarian for proper evaluation.
  • Lethargy: Unexplained and prolonged lethargy or weakness can be a sign of an underlying health issue, including metabolic disorders like MCAD deficiency.
  • Episodic Illness: These episodes can include vomiting, decreased energy levels, and more severe symptoms like seizures.
  • Unsteady Gait: Difficulty walking, balance issues, or uncoordinated movements might be observed during episodes of illness.
  • Loss of Appetite: If your CKCS suddenly loses interest in food or experiences a decreased appetite, it could be a symptom of an underlying condition.
  • Low Blood Sugar (Hypoglycaemia): MCAD deficiency can lead to hypoglycaemia, which may cause weakness, shakiness, disorientation, and even seizures
  • Abnormal Behaviour: Changes in behaviour, such as increased irritability or confusion, can sometimes be indicative of a metabolic disorder.
  • Respiratory Distress: In severe cases, dogs might experience difficulty breathing or rapid breathing during an episode.
    Recurrent Infections: Some dogs with MCAD deficiency may have a higher susceptibility to infections.
  • Neurological Symptoms: Dogs with MCAD deficiency may exhibit neurological symptoms during episodes, such as circling, head pressing, or lack of coordination.

MCADD: Medium-chain Acyl-CoA Dehydrogenase Deficiency in CavaliersObviously these can be signs and symptoms of other conditions too, so keep records and have your dog evaluated. Many veterinarians WILL NOT yet be aware of MCADD so please show them this information.

The research needs more Cavaliers to be tested!  It’s an inexpensive, simple swab test kit that you can order and complete at home. Over 200 dogs have been tested in UK and Europe, with similar results – Clear: 35%, Carriers: 53%, Affected: 12%. ALL breeding dogs need to be tested.