Dogs and the Shape of Their Heads

New Research Points to the Importance of Headspace

Rosie – CM Headache
Rosie – CM Headache

In recent years, nobody could have failed to have noticed the boom in popularity of dog breeds such as Pugs, French Bulldogs and Boston Terriers. These breeds have a skull which is wider than it is long, defined as “brachycephalic”. Many less-obviously “flat faced” dogs are also brachycephalic, including Cavalier King Charles Spaniels.

While it is generally accepted that such head conformation can be associated with health problems such as breathing and eye issues, a new research paper published by Professor Clare Rusbridge and Dr Penny Knowler points to increasing evidence that brachycephaly can also impair the circulation of cerebrospinal fluid leading to distressing and life-limiting conditions such as hydrocephalus and CM/SM (syringomyelia).

Many of the brachycephalic breeds more likely to suffer from such conditions, including Cavaliers, Chihuahuas and Pugs, are hugely popular pets. The research paper concludes by questioning whether it is ethical to breed dogs predisposed to these issues and stresses the importance of educating the puppy-buying public about the importance of avoiding extreme conformation. It also calls for wider screening of (at risk?) breeding dogs (rather than stock, some people take offence at the term stock).

There is an official Kennel Club screening scheme for Chiari-like Malformation of the skull and Syringomyelia but it is not compulsory, nor widely used. Furthermore, a recent analysis of Cavalier litters registered by the Kennel Club in 2020 revealed that only four litters (out of 705) show evidence of any kind of screening for these two conditions and only two of the litters would have passed the breeding guidelines.

The cost of a screening MRI in the UK is £200 to £300 plus BVA reading fee £100. Cavalier puppies from fully health tested parents sell for £2,500 to £4,000 plus so cost should not be a deterrent in having the parents scanned.