Chihuahua Skull: Understanding the Molera or Fontanelle in Chihuahuas
Chihuahuas are popular tiny toy dogs known for their big personalities and adaptability to small homes. Despite their delicate size, they tend to be generally healthy, but owners and potential buyers should be aware of some unique breed traits and potential concerns.
One distinctive feature in many Chihuahuas is the presence of a molera, also called a fontanelle or soft spot, which is a gap or opening in the skull that can often be felt as a soft area on top of the head. This trait, while not present in every dog, is quite common and usually closes naturally as the dog matures — though sometimes it may persist lifelong. Understanding the molera is important for owners and breeders alike, as it influences certain care considerations.
What is a molera?
A molera is a soft spot located at the junction where the frontal and parietal bones of the skull meet, typically a few inches above the centre of the nose towards the top of the head. It may be round or diamond-shaped and usually measures less than an inch across. The edges can be smooth or slightly irregular.
This fontanelle is not unique to Chihuahuas; it also appears in other dog breeds and in human infants. In Chihuahuas, it's a breed characteristic, often persisting into adulthood.
How common is the molera in Chihuahuas?
Although the presence of a molera was once regarded as a sign of purity and included in breed standards, The Kennel Club no longer mentions it specifically. However, studies show that up to 80-90% of Chihuahua puppies are born with a molera.
Smaller Chihuahuas and those with the typical "apple head" shape are more likely to have the molera trait. Most pups’ moleras close within the first few months, but in some dogs, it remains into adulthood.
Does the molera close as the puppy grows?
In many cases, the molera gradually closes as the skull bones fuse during growth. This process usually completes within 18 months but can take longer. Some adult Chihuahuas retain a small soft spot on their skull indefinitely.
Regular veterinary check-ups can confirm if the molera is closing and advise on necessary precautions.
Are moleras harmful to Chihuahuas?
The molera itself is not considered a defect or disease in Chihuahuas. Most dogs live normal, healthy lives with a molera if properly cared for and protected.
However, because the molera is an area where the skull is thinner or open, it is a more vulnerable spot that can be injured by bumps or falls. Owners should take care to protect their dog's head from injury without being overly protective.
Historically, it was suspected that moleras were linked to hydrocephalus (fluid accumulation in the brain), but modern veterinary research finds no direct connection. Still, hydrocephalus and epilepsy are health concerns in the breed, and a molera could raise risks during seizures if a dog hits its head.
If your Chihuahua has a molera, please inform your vet so they can monitor it and offer advice on safe care.
How to care for a Chihuahua with a molera
- Be mindful of head injuries: Avoid rough play and situations where your dog might bump its head.
- Observe for symptoms: Watch for neurological signs such as seizures, disorientation, or changes in behaviour and seek veterinary advice if they occur.
- Regular vet checks: Keep up routine veterinary appointments to monitor skull development and overall health.
- Provide a safe environment: Use soft bedding and supervise interactions during puppyhood to limit accidental impacts.
Remember, owning a Chihuahua with a molera means being aware and cautious without creating unnecessary worry.
What should you ask when buying a Chihuahua puppy?
When looking to find a Chihuahua puppy, ask reputable breeders about the presence of a molera and any health monitoring they do. Responsible breeders prioritise the welfare and health screening of their puppies, including regular veterinary checks.
It's important to understand breed-specific health issues and ensure your new dog is well cared for from the start.
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Chihuahua skull summary
The molera, or fontanelle, is a common and largely benign trait in Chihuahuas. While it may persist into adulthood, it rarely causes issues if the dog is protected from head injuries and monitored regularly by a vet.
Understanding this unique feature helps owners provide responsible care and maintain their Chihuahua’s health and happiness.
