A new study from the University of Surrey,
published today in the journalPLOS One, has identified the specific
effect Chiari malformation has on the shape of a dog's skull and brain. This condition
has become prevalent as a result of selective breeding and affects many toy dog
breeds which have been bred to look more doll-like, including Griffon
Bruxellois, Cavalier King Charles Spaniels, Chihuahuas and their crosses.