New Research into Devastating Disease Affecting Cavalier King Charles Spaniels
Researchers at the Royal Veterinary College have found that Cavalier King Charles Spaniels affected by syringomyelia and Chiari-like malformation, have an irregular, “drunk-like” gait, measured in variation of gait characteristics, and a wider distance between the thoracic limb paws resulting in a wider base of support when walking.
Cavaliers are sweet and adorable little dogs that are loved by the public. Sadly, a significant proportion of cavaliers are predisposed to a painful and debilitating spinal cord condition known as syringomyelia. The condition is characterised by fluid-filled cavities called syrinxes within the spinal cord which, as they grow, cause pain and neurological deficits. Dog breeds that are miniaturised and short-nosed are more prone to syringomyelia, but Cavaliers are believed to be the most commonly affected breed.
The study used a simple and novel technique for quantifying gait parameters using a grid on the ground made of electrical tape and two high-speed video cameras. These gait changes are similar, even when less severe, to dogs with spinal cord disease in the first part of the neck and cerebellar disease in humans. The study compared Cavaliers to Border Terriers.
The Cavalier has an increased variation of the gait parameters stride length, paw distance on the same side and distance between the front paws when walking. The increased variation of walking gait demonstrates a need for wider based support to increase stability, similar to young children and foals and humans with cerebellar ataxia and spinal cord diseases in the neck. Our results add to the body of evidence showing that by breeding for paedomorphic features, dogs have a puppy-like gait in addition to inadvertent alterations of behaviour, skull and brain morphology.
As humans, we have a preference for infantile (baby-like) features and this unconsciously biases our selection of companion animals as pets. The Cavalier shows paedomorphic (baby-like) behaviour and infantile facial features with large eyes, and a large flattened forehead. Selecting for paedomorphic traits changes the morphology of the skull and has selected for an oversized cerebellum in the cavalier. The cerebellum coordinates balance and locomotion from sensory inputs via the spinal cord and brain.
Professor Holger Volk, Head of Department, Clinical Science and Services and specialist in Neurology and Neurosurgery said: “We know the cavalier King Charles spaniel can be affected by pain associated with syringomyelia and this study highlights that coordination of gait appears to be affected as well.”
Co-author of the study and Neurology Resident at Cornell University in Ithaca, New York, Dr Emil Olsen, added: “A breeding selection for paedomorphic features and these inherent abnormalities of the cerebellum we already know the cavalier King Charles spaniel has, and formation of syrinxes, not only causes pain but also appear to affect how they walk. This could be a simple monitoring tool for long-term health and assist breeding of sound dogs.”
As well as Syringomyelia, Cavaliers suffer in high numbers from an inherited heart condition called Mitral Valve Disease (MVD). Over 30,000 people have signed an online petition asking the Kennel Club to only register puppies from Cavaliers screened for these conditions. To view and sign the petition, visit the following website: https://www.change.org/p/the-kennel-club-stop-registerin-g-cavalier-king-charles-spaniel-puppies-unless-their-parents-are-mri-scanned-and-heart-tested
The research paper is published in BMC Veterinary Research DOI: 10.1186/s12917-017-1077-5