Despite the Hokkaido Ken having a relatively small gene pool, they are a fairly healthy breed. Below are some of the known conditions that may affect the Hokkaido. Please note this list in incomplete due to the small gene pool. These conditions may not be breed specific, but have been seen occasionally in the Hokkaido. Due to our kennel owner being in the veterinary profession, we feel it is incredibly important to provide clear, accurate information on the health of the breed, however we are not a substitute for your veterinary practice. We take health testing very seriously.

This information is kindly provided by the Nihon ken Network

Collie Eye Anomaly (CEA) Choroidal Hypoplasia

Collie Eye Anomaly (CEA) is the biggest issue within the Hokkaido Ken. It is estimated that around 2/3rd of the population are carriers of the condition, and 1/3rd are affected. Carriers will never develop the disease, but can pass it onto offspring. It is unknown how the condition got into the Hokkaido, as its nickname suggests, mainly affects collie breeds. It is not generally progressive; however in severe cases, it can lead to secondary complications, which may cause vision loss. There is no treatment for CEA. Dogs that are affected with this condition are recommended to not be bred from, however, carriers of this condition, may breed, but breeding should be incredibly selected, and preferably with another dog who is completely clear and not affected at all by this condition. Regular check ups and eye exams at the vets is recommended to document the progression of the disease.

Heart Murmurs

Heart murmurs are detected by your vet (normally at first or second vaccination) when the vet hears a whooshing sound in the heart. In dogs, common causes include heart valve problems, heart defects, tumours, or weakening of the heart muscle. It isn’t always a cause for concern, but it can be. Vets will grade this heart murmur from 1 to 6; with Grade 1 being incredibly mild, Grade 6 being severe. Mild heart murmurs which are detected in young puppies are something that may be ‘grown out of’, and should be re-evaluated after a few months to check for improvement.


The most common cause of seizures in dogs is idiopathic epilepsy. It is genetic and the cause is unknown. Seizures are when the brain has uncontrolled episodes of electrical activity. It can cause dogs to fall to the floor, have behaviour changes (become aggressive or disorientated), and can last up to several minutes. There are a number of reasons your dog can develop a seizure such as diagnosed epilepsy; ingesting poison; low or high blood sugar; kidney disease; head injury; brain cancer; and brain swelling. The most common kind is the generalized seizure, also called a grand mal, where a dog can lose consciousness and start to convulse violently. The abnormal electrical activity happens throughout the brain. Generalised seizures usually last from a few seconds to a few minutes. With a focal seizure, abnormal electrical activity happens in only part of the brain. Focal seizures can cause unusual movements in one limb or one side of the body. Sometimes they last only a couple of seconds.


Pica is a condition in which dogs crave and eat non-food items. Some dogs may only eat one type of object, while others will eat a wide variety of items. Pica can endanger a dog’s health because what they swallow may be toxic; disrupt normal digestive process; or get lodged in their intestinal tract. It is unknown what causes Pica, but it has been linked to separation anxiety, and stress. Most dogs will crave items that carry their owners’ scent, with socks, underwear, or children’s toys being the most common. There is not exact treatment for pica, although vets will try to identify if there is an underlying health or behavioural condition causing it. If there is no specific cause, then you must prevent the pica itself: this normally will involve the dog permanently wearing a basket muzzle on walks and keeping them on lead (if they eat items outside); or removing toys/clothing/items that they are craving (when inside the house) and storing them in a locked cabinet/wardrobe that the dog cannot access

Pacific Rimism

Pacific Rimism is the name given to a condition that often affects dogs from the Pacific Rim (specifically Japanese Dogs, such as the Hokkaido Ken). It is a condition that causes the blood potassium levels to be very elevated. In these breeds of dog, this elevation can be completely normal and is seen commonly. Japanese breeds such as the Hokkaido Ken are still quite uncommon in the UK, meaning that Vets may not be well informed of this condition. High levels of potassium in the blood, are also found with Addisons Disease. These high levels are often found by accident, such as at routine blood tests during neutering, or when the pet is taken to the vets for being unwell. These high levels of potassium can be very confusing to not only owners, but also to vets. Before your vet diagnoses your Hokkaido with Addisons disease, make sure they run an ACTH Stimulation test to prevent a misdiagnosis of Addisons Disease. Dogs that have a normal ACTH stimulation test result do NOT have Addisons disease. However if the result is abdormal in the ACTH stimulation test, your dog will test positive for Addisons Disease.


Cryptorchidism is observed in the Hokkaido. Cryptorchidism is where one, or both testicles do not descend form the body at around 2-4 months old. Cryptorchidism can be linked to male infertility, and the undescended testicle is up to 13 times more likely of becoming cancerous. The exact cause is not understood, however, it is genetic and male dogs who suffer from this condition are recommended to be neutered and not used for breeding. It is important to remember that males who have one testicle descended may still be able to mate, so it is recommended that they are kept away from bitches in heat until castration. Dogs with cryptorchidism are normally completely healthy otherwise, and lead happy, healthy lives.

Hip & Elbow Dysplasia

Hip and elbow dysplasia are terms used to describe abnormal formations of the hip socket and elbow joint that, in its more severe form, can eventually cause crippling lameness and painful arthritis of the joints.

The British Veterinary Association (BVA) recommends all dogs to be screened and tested for hip and elbow dysplasia, this is done via x-rays under general anaesthetic at your vets, where the x-rays’ are then sent off to the BVA to be scored. Dogs that receive poor hip and elbow scores are not recommended to be bred from. Hip and elbow dysplasia can be managed by maintaining a good weight, medication (anti inflammatory pain relief), physiotherapy, and lifestyle changes. If severe enough, it can be treated surgically. Please note that surgically managing your dogs’ hip and elbow dysplasia may remove the problem, but will still not make them suitable to breed from as these conditions are genetic.

[*Please note that other countries have their own methods of scoring. Please contact the relevant governing veterinary body of your country to find out more]