Dogs With Dwarfism: Everything You Need To Know

Key takeaway

Dwarfism can affect dogs in a variety of ways, from more benign, aesthetic physical characteristics such as a larger than normal head to more severe medical issues such as hypothyroidism and spinal deviations. The two main types of canine dwarfism are achondroplasia and pituitary dwarfism. While achondroplasia is selectively bred in some dog breeds, pituitary dwarfism often requires medical intervention and can shorten the lifespans of dogs affected.

Can dogs have dwarfism? Yes, just like humans, dogs can be affected with dwarfism. Dwarfism in dogs can cause both relatively benign, aesthetic issues such as a larger than normal head and more severe issues that impact their quality of life like spinal deviations. Depending on which type of dwarfism a dog has, they may be affected by their condition very differently. Dogs with skeletal forms of dwarfism may be more prone to diseases that limit their mobility, but dogs that have inherited pituitary dwarfism tend to unfortunately have considerably shorter lifespans. 

Some dog breeds like Dachshunds and Basset Hounds are even bred for dwarfism, with a low-to-the-ground silhouette and short legs being a part of their official breed standard.1 This article will take a closer look at the different types of dwarfism in dogs, how they are diagnosed, if they have any treatment options, and how to help dogs with dwarfism live with and manage their disease. Read through the entire article to get the whole picture of dog dwarfism or use the links below to jump to a specific section. 

What Is Dwarfism in Dogs?

Dwarfism is a medical or genetic condition that causes a dog to be considerably smaller or shorter than an average sized dog of their breed. However, some dog breeds are selectively encouraged to express dwarfism, whether that is for aesthetic reasons or to better perform at their jobs. Dachshunds, for example, were bred to have extremely short legs in order to be a better hunting companion; their short stature allows them to crawl into dens and tight spaces, flushing out badgers and other animals for their owners.1 

Types of Dwarfism in Dogs

Achondroplasia

Achondroplasia is a type of osteochondrodysplasia, a group of hereditary disorders that causes abnormal development of the skeleton, mainly affecting the connective tissues, joints, and bones. Dogs with achondroplasia are affected with a disproportionate skeletal dwarfism in which their bones do not grow to the normal size that is conventional to their breed.2 While the exact cause and location of achondroplasia in dogs is unknown, a mutation in the transmembrane domain of the fibroblast growth factor receptor-3 gene is what causes achondroplasia in humans.3 

This is the type of dwarfism that is encouraged in certain dog breeds such as Bulldogs, Pugs, Boston Terriers, and Basset Hounds. 

Common achondroplastic dog breeds

Pituitary Dwarfism

Pituitary dwarfism in dogs is also known as juvenile-onset panhypopituitarism. It is most commonly caused by a failure of the pituitary gland to develop in utero, resulting in a lack in production of trophic hormones responsible for the growth and function of certain endocrine cells. Pituitary dwarfism in dogs can also be caused by benign brain tumors that affect the pituitary gland, leading to lower levels or the complete absence of growth hormones.4

Pituitary dwarfism is an inherited autosomal recessive trait, meaning two copies of the associated gene have to be present for this disease to develop. Dogs with pituitary dwarfism will deviate in healthy growth from normal dogs of their breed at around two months of age, only reaching skeletal maturity at about four years old. This is often a proportional type of dwarfism and affected dogs often have shortened life spans.4 

Pituitary dwarfism is most common in dog breeds such as:

  • German Shepherd
  • Spitz
  • Miniature Pinscher
  • Karelian Bear Dog
  • Weimaraner

Signs Of Dwarfism In Dogs

Achondroplasia

Dogs with achondroplasia may develop physical characteristics such as:

  • Larger head
  • Shorter nose
  • Shortened jaw
  • Crooked teeth
  • Enlarged joints
  • Crooked spine
  • Shorter limbs
  • Bowed limbs
  • Corkscrew tail2 

Dogs with achondroplasia are often affected by spinal issues as well. Spina bifida, in which the spine fails to develop properly, and spinal deviation are commonly noted in dogs with this type of dwarfism. Hemivertebrae, intervertebral disc disease, and rotational limb deformities may be exhibited as well. Dogs affected with this form of dwarfism may have trouble breathing. Achondroplastic dogs are more prone to obesity, dog arthritis, limping or difficulty walking, and other issues associated with mobility because of their deformities, so pet parents must take extra care that they are comfortable and getting an adequate amount of exercise that suits them.2 

Dogs with achondroplasia are at a higher risk for obesity and more prone to arthritis

Pituitary Dwarfism

Starting at around two months old, dogs with pituitary dwarfism may exhibit signs including:

  • Slow and stunted growth
  • Retention of puppy coat
  • Delay or absence of adult teeth
  • Alopecia
  • Slow closure of growth plates
  • Poor development of sex and reproductive organs
  • Irregular or lack of estrus
  • High-pitched bark
  • Endocrine dysfunction4

If the pituitary dwarfism was caused by a benign tumor in the dog’s brain, the tumor may continue to extend across the hypothalamus, affecting the function of certain cranial nerves and the autonomic nervous system. This may cause specific nerve function deficits and issues in essential functions affecting temperature regulation, sleep, thirst, and hunger. 

Pituitary dwarfism in dogs also often results in a considerably shortened lifespan. In most cases, this is due to the endocrine dysfunction that presents as a secondary issue. Conditions such as hypothyroidism in dogs, Cushing’s disease, and hypoadrenocorticism can arise due to pituitary dwarfism.4

Diagnosing Dwarfism In Dogs

While it may seem obvious by appearance that your dog has dwarfism, veterinarians will still run tests to confirm the diagnosis. Especially if your dog is not a breed that is especially bred for dwarfism, it is crucial to verify if they are affected by pituitary dwarfism as it is a disease that can markedly affect your dog’s quality of life and even shorten their life spans. 

To diagnose pituitary dwarfism, your veterinarian may first ask you for a detailed medical history of your dog. This will include when you first noticed any abnormalities in your dog’s growth and development and genetic information of your dog’s lineage. Pituitary dwarfism is an inherited disease and dogs will show signs of stunted growth as early as around two months in age. 

Then, to eliminate any other potential causes, your vet may conduct basic diagnostic tests such as a complete blood count, urinalysis and biochemistry profile. MRIs and CT scans may also be requested to check for the presence of any tumors. X-rays may also be taken of any affected parts of the body, including the limbs and spine, and a sample of the bones may be sent to a pathologist for further examination.2

Endocrine tests, growth hormone stimulation tests, insulin growth factor tests, thyroid hormone stimulating tests, and follicle-stimulating hormone tests may be performed as well to test for pituitary dwarfism in dogs. Insulin hypersensitivity, lower cortisol levels, delayed growth plate closure, absent hair shafts are common in dogs affected with pituitary dwarfism.4 

German Shepherd puppy with mother outdoors on fallen leaves

Treating Dwarfism In Dogs

Achondroplasia in dogs has a limited number of adverse effects; these effects tend to be less severe and less likely to require medical intervention when compared to pituitary dwarfism. Depending on how severe the achondroplasia is, anti-inflammatory medication or pain relievers may be used to ease any discomfort your dog is experiencing. Consult a veterinarian to ensure your dog gets the support they need.  

To treat pituitary dwarfism, your vet may recommend either of the below options:

  • Hormone supplementation: Your vet may recommend hormone supplementation for the secondary hypothyroidism experienced by your dog as a result of pituitary dwarfism. Your dog must be closely monitored during this process. Growth hormones or megestrol acetate, a man-made version of progesterone, may also be used to promote the release of growth hormones from your dog’s mammary tissue. Progesterone supplementation can potentially reverse some of the signs associated with canine dwarfism, but it comes with many unwanted effects such as insulin resistance and mammary hyperplasia.4 
  • Surgery: If the pituitary dwarfism is the result of a tumor, surgery may be an option as long as the tumor is not in an especially vital and delicate area. Surgery may not be recommended if the chance of properly recovering is low. 

Hormone supplementation for pituitary dwarfism can have side effects such as insulin resistance and mammary hyperplasia

Managing Dwarfism In Dogs

Achondroplasia

Dogs with achondroplasia can live relatively normal lives, especially if their breed is one bred to be achondroplastic. There is not much we have to do differently as pet parents to keep them healthy and happy. However, as dogs with achondroplasia age, you may have to be more conscious of the conditions they are predisposed to, such as obesity, arthritis, other joint disorders causing joint pain, and spine issues. These conditions can be managed, but work closely with your vet to continuously monitor your dog’s circumstances. 

Pituitary Dwarfism

Pituitary dwarfism in dogs usually requires medical intervention, whether that is trying to reverse some of the clinical signs of dwarfism with hormone supplementation or attempting to make your dog feel more comfortable with other medication. Dogs with pituitary dwarfism tend to have shortened lifespans, but treated dogs are significantly taller and heavier and have better quality of life. 

Dogs With Dwarfism: Frequently Asked Questions

How can you tell if a dog has dwarfism?

A dog with dwarfism will likely appear smaller or shorter than a normal dog of the same breed. Dogs with achondroplasia are disproportionately smaller, with shorter limbs but normal or larger heads for example. Dogs with pituitary dwarfism are proportionately smaller, appearing like a puppy rather than a fully grown dog of their breed. In general, look out for shorter limbs, bowed limbs, crooked spine, and enlarged joints.

How common is dwarfism in dogs?

Achondroplasia is an extremely common form of dwarfism in dogs as many breeds are selected for this trait. However, pituitary dwarfism is a very rare condition. Pituitary dwarfism is most common in German Shepherds. 

Side view of Dachshund outdoors standing on a log

Final Notes

Dogs with achondroplasia can typically live normal and healthy lives. Dogs with pituitary dwarfism, however, benefit from medical intervention to reverse certain clinical signs of dwarfism and extend their lifespan. If you suspect your dog to be affected with pituitary dwarfism, contact a vet for an accurate diagnosis as soon as possible. 

If you have more questions about dogs with dwarfism or how to help your dog with dwarfism manage their disease, contact a Dutch licensed vet today. As an accessible and high quality resource for all pet parents, we can help your pet from the comfort of your home when your local veterinarian is out of office. Try Dutch today. 

References

  1. "Dachshund." American Kennel Club, https://www.akc.org/dog-breeds/dachshund/

  2. "Bone Deformity and Dwarfism in Dogs." PetMD, 20 Sep. 2009, https://www.petmd.com/dog/conditions/Musculoskeletal/c_dg_osteochondrodysplasia

  3. Martinez, S. et al. "Achondroplastic dog breeds have no mutations in the transmembrane domain of the FGFR-3 gene." Canadian Journal of Veterinary Research, Oct. 2000, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1189626/

  4. Greco, Deborah S. "Juvenile-onset Panhypopituitarism in Dogs (Pituitary dwarfism)." Merck Veterinary Manual, Oct. 2022, https://www.merckvetmanual.com/endocrine-system/the-pituitary-gland/juvenile-onset-panhypopituitarism-in-dogs