Open Fontanelle In Small Breed Puppies: Expert Guide

Open Fontanelle in Small Breed Puppies

Just like human babies, puppies are born with open fontanelles, commonly known as soft spots in the skull. These openings are particularly common in small and toy breed dogs such as Chihuahuas, Pomeranians, Yorkshire Terriers, and Toy Poodles. In some breeds like Chihuahuas, these soft spots, called moleras, are considered part of the breed standard. While most puppies’ fontanelles close naturally during their first few months of life, understanding this condition is essential for responsible pet ownership and ensuring your puppy receives proper care and monitoring.

What Is an Open Fontanelle?

An open fontanelle is an opening or soft spot in a puppy’s skull located where the growth plates have not yet fused together. During development, the bony plates of the skull are separated and somewhat soft, allowing them to flex as the puppy passes through the birth canal during delivery. After birth, these plates gradually fuse and become rigid through a natural process called ossification. The last place to fill in and solidify is typically the spot at the top of the skull where the four skull plates meet, creating what veterinarians call a fontanelle.

Open fontanelles are openings between the growth plates in the skull that normally close as a puppy develops and matures. These soft spots play an important role during birth and early development by allowing the skull to compress and pass through the birth canal without injury to the puppy or complications during delivery. As growth continues, these gaps gradually close as the bone plates fuse together in a process that typically takes several weeks.

Normal Timeline for Fontanelle Closure

Most puppies’ fontanelles close naturally during their early months of life. In smaller breeds like Shih Tzus, an open fontanel usually closes by the time the puppy is about four weeks old, and almost always by four months old. For Chihuahuas and other toy breeds, the typical timeframe for fontanelle closure is between 9 to 12 weeks of age. However, veterinarians generally monitor the fontanelle at each puppy visit and consider it a persistent open fontanelle if it hasn’t closed by approximately 3 to 4 months of age.

It’s important to note that in some very tiny breeds, particularly Chihuahuas, the fontanel may never close completely, and this is considered normal for the breed. Breed standards for certain toy breeds actually include the presence of an open fontanelle as an acceptable characteristic. However, a fontanelle that remains open beyond the typical closure period in breeds where closure is expected may indicate an underlying concern that requires veterinary attention.

Diagnosis and Veterinary Monitoring

The diagnosis of an open fontanelle is usually made during a physical examination by your veterinarian. During your puppy’s first veterinary visit, your vet will feel the top of the skull to detect any soft spots or openings. This simple palpation technique allows the veterinarian to confirm the presence and size of any fontanelle and establish a baseline for monitoring as your puppy grows.

Your veterinarian will continue to monitor the open fontanelle at each subsequent puppy visit to track its closure progress. If the fontanelle remains open beyond the expected closure timeframe for your breed, your vet may recommend additional diagnostic imaging such as X-rays, ultrasound, or other advanced imaging techniques to rule out underlying conditions like hydrocephalus or other neurological issues. Early detection of potential problems through regular monitoring allows for timely intervention if needed.

Types and Causes of Open Fontanelles

There are two main categories of open fontanelles: normal fontanelles that close on schedule and persistent open fontanelles that remain open beyond the typical closure period. Understanding the difference between these categories and their underlying causes is crucial for proper puppy care.

Normal Open Fontanelles

Normal open fontanelles are a standard part of puppy development and close naturally as the skull plates fuse. These require no treatment and typically pose no health concerns as long as they close within the expected timeframe.

Persistent Open Fontanelles

Persistent open fontanelles are those that remain open beyond 3 to 4 months of age and may be caused by several factors:

• Genetic abnormality or hereditary predisposition
• Hydrocephalus (fluid accumulation in the brain)
• Underlying brain conditions
• Brain infections or inflammation
• Brain tumors
• Disease processes that block cerebrospinal fluid drainage

Genetic factors play a significant role in the development of persistent open fontanelles. Because this condition is considered a genetic abnormality, puppies with persistent open fontanelles should not be bred to prevent passing the condition to future generations.

Breeds Predisposed to Open Fontanelles

While open fontanelles can occur in any breed, certain small and toy breeds are significantly more predisposed to this condition. Understanding whether your breed is at higher risk can help you be more vigilant in monitoring your puppy’s development:

• Chihuahuas
• Pomeranians
• Yorkshire Terriers
• Toy Poodles
• Shih Tzus
• Maltese
• Miniature Dachshunds
• Boston Terriers
• Pekingese
• Cairn Terriers
• Lhasa Apsos
• English Bulldogs

The genetic prevalence of open fontanelles in these breeds makes regular veterinary monitoring even more important for early detection of any potential complications.

Symptoms and Clinical Signs

While many puppies with open fontanelles show no symptoms and develop normally, certain clinical signs may indicate a problem that requires veterinary attention. Parents of small breed puppies should watch for the following symptoms:

• A soft spot or hole in the skull, usually located on the top of the head
• Dome-shaped or apple-shaped skull appearance
• Eyes that seem to point upwards or downwards
• General problems with coordination or clumsiness
• Head pressing against objects
• Difficulties with housetraining
• Slow growth or failure to grow at normal rates
• Restlessness or inability to settle
• Aimless wandering or pacing

More serious symptoms that may indicate hydrocephalus or other neurological complications include seizures, blindness, severe lack of coordination, walking in circles, or an enlarged, domed head. If you notice any of these symptoms in your puppy, contact your veterinarian immediately for evaluation and diagnosis.

Associated Conditions and Complications

Hydrocephalus (Water on the Brain)

Very rarely, a puppy with an open fontanel may have a serious medical condition called hydrocephalus, commonly referred to as water on the brain. This condition occurs when too much cerebrospinal fluid accumulates within and around the brain, creating pressure that may damage or prevent the proper development of critical brain tissue.

A hydrocephalic puppy typically exhibits noticeable symptoms by four months of age, including seizures, blindness, lack of coordination, difficulty walking in straight lines, and an enlarged domed skull. While an open fontanel itself does not necessarily mean a dog will develop hydrocephalus, most dogs diagnosed with hydrocephalus will have open fontanelles. It is not uncommon for fontanels in toy dog breeds to remain open throughout their lives without causing hydrocephalus or other problems.

Unfortunately, there is no cure for hydrocephalus itself. However, in some cases, veterinarians may prescribe medications to decrease the production of cerebrospinal fluid, which can help manage mild to moderate cases. In more severe cases, surgical placement of a shunt may be considered to redirect excess fluid. Additional surgeries are often required as the puppy grows to re-fit the shunt, and the success rate for this procedure is approximately 80 percent.

Treatment Options and Management

Unfortunately, there is no direct medical treatment for an open fontanelle itself. Because this condition is considered a genetic abnormality, affected puppies should not be used for breeding purposes to prevent transmission of the condition to future generations.

However, management strategies focus on preventing complications and ensuring your puppy lives a normal, healthy life:

Lifestyle and Environmental Modifications

For puppies with open fontanelles that pose no serious health concerns, the primary management strategy involves making lifestyle and environmental changes to minimize the likelihood of head trauma:

• Avoid rough play or contact sports that could result in head injury
• Prevent falls from heights such as furniture or beds
• Use protective headgear in some cases to shield the affected area
• Supervise interactions with children and other animals
• Maintain a safe, trauma-free living environment
• Consider housing your puppy in a family without small children or other animals if the fontanelle is particularly large or vulnerable

Veterinary Monitoring

Regular veterinary check-ups are essential for puppies with open fontanelles. Your veterinarian will monitor the fontanelle’s closure progress at each visit and watch for any signs of complications or underlying conditions. If symptoms develop, your vet may recommend additional diagnostic imaging to evaluate the puppy’s condition further.

Prognosis and Long-Term Outlook

The long-term prognosis for puppies with open fontanelles depends on the severity of the condition and the presence of any associated health issues. If a puppy has an open fontanelle but no other medical complications, the prognosis is generally excellent. These puppies can live long, healthy lives as long as they receive no direct trauma to the head and are managed appropriately.

Some puppies’ fontanelles may close later than typical, and this delayed closure is not necessarily cause for alarm. While symptoms in some dogs may resolve within two years, other cases may require more long-term management or repeated treatments if medications or surgical interventions become necessary.

With proper precautions and veterinary oversight, most puppies with open fontanelles grow into healthy adult dogs with no significant health problems. The key is maintaining a safe environment, providing regular veterinary monitoring, and being attentive to any changes in your puppy’s behavior or development.

Breeding Considerations

If you are breeding small breed dogs, it is crucial to understand the implications of open fontanelles. Because this condition is considered a genetic abnormality, dogs with open fontanelles should not be bred. Preventing open fontanelles and related conditions in future generations requires careful breeding practices and refraining from breeding affected dogs.

If you have a breed of dog known for these conditions, monitor your puppy’s growth carefully and seek advice from your veterinarian if you notice any associated symptoms. Responsible breeders should screen for this condition and work toward reducing its prevalence in their breeding lines.

Frequently Asked Questions

Q: How can I tell if my puppy has an open fontanelle?

A: Your veterinarian will examine your puppy during routine visits and can feel for a soft spot on the top of the skull. You may also notice a slight depression or soft area on top of your puppy’s head. Always consult your veterinarian for a proper diagnosis rather than attempting to diagnose this condition yourself.

Q: Is an open fontanelle in my puppy dangerous?

A: An open fontanelle itself is not necessarily dangerous, particularly if it closes on schedule or if your puppy shows no other symptoms. However, the soft spot does leave the brain slightly more vulnerable to injury, which is why trauma prevention is important. Serious complications are rare but can occur if an underlying condition like hydrocephalus is present.

Q: When should an open fontanelle close?

A: Most puppies’ fontanelles close between 9 to 12 weeks of age, though timing varies by breed. Your veterinarian will monitor closure progress at each visit and typically considers it a concern if the fontanelle hasn’t closed by 3 to 4 months of age. Some toy breeds may have fontanelles that never fully close.

Q: Can open fontanelles be treated?

A: There is no direct treatment for open fontanelles themselves. Management focuses on preventing head trauma through environmental modifications and protective measures. If an underlying condition like hydrocephalus is present, your veterinarian may recommend medications or surgery to manage that specific condition.

Q: Should I be concerned if my puppy’s fontanelle hasn’t closed by three months?

A: While some delay in closure may be normal, a fontanelle that remains open beyond 3 to 4 months should be evaluated by your veterinarian. This does not necessarily indicate a serious problem, but it warrants professional assessment to rule out underlying conditions and establish an appropriate monitoring plan.

Q: Can I breed a dog with an open fontanelle?

A: No, dogs with persistent open fontanelles should not be bred. Because this condition is considered a genetic abnormality, breeding affected dogs can pass the condition to offspring. Responsible breeding practices include avoiding breeding dogs with this condition to reduce its prevalence in future generations.

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Sneha TeteBeauty & Lifestyle Writer

 

Sneha is a relationships and lifestyle writer with a strong foundation in applied linguistics and certified training in relationship coaching. She brings over five years of writing experience to fluffyaffair,  crafting thoughtful, research-driven content that empowers readers to build healthier relationships, boost emotional well-being, and embrace holistic living.

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