The UKKC lists the following defects as being a problem in the Chihuahua:
- Incorrect dentition
- Wry jaw
- Retained puppy teeth
- Misplaced teeth
- Protruding tongue as a result of incorrect teeth
- Missing teeth
- Incorrect bites
- Excessively short muzzles.
You could select any one of those and feel that the poor dog would need it like a hole in the head, but that is exactly what has been added to the litany of defects for the poor Chihuahuas: holes in the head.
Our colleagues at Pedigree Dogs Exposed have alerted us to a new paper which highlights the prevalence of persistent fontanelles – holes along the suture lines of the skull that expose the encased brain. Fontanelles are normal soft spots that enable growth and birth, but that should close between 9 and 12 weeks of age.
The failure of this process is common in small dogs, especially where breeders have deliberately created domed heads and smaller and smaller dogs. Some breeders have even made a fetish of an open fontanelle in the middle of the head (designated as a molera) and supposedly designating the “purity” of the breed.
This latest finding and earlier research by the same authors shows that as many as 90% of Chihuahuas suffer from holes in the skull: the smaller the dog, the larger the hole and the larger the amount of brain area exposed. There is also an association with syringomyelia and ventriculomegaly.
The simple solution is to breed bigger dogs without domed heads and short narrow muzzles. The difficulty is in persuading the breeders and show judges – the very people who purport to uphold the best in the breed – to agree and comply.