Health Testing Guide
Which tests are mandatory, how to spot responsible breeders — and what it costs when things go wrong.
For the Shetland Sheepdog we have compiled 5 mandatory and 11 recommended health tests, drawn from breed-club regulations, the University of PEI (CIDD), and OMIA — weighted by severity and heritability.
What this grade means
The Shetland Sheepdog is classified as healthy because typical risks are well-managed through targeted breeding practices. Hip dysplasia (HD) is monitored via mandatory health tests, while M-locus issues (merle inheritance) require careful pairing to prevent health defects in puppies. Buyers should specifically ask to see the test results of the parent dogs.
Every breed is susceptible to certain inherited conditions. Just like humans, dogs inherit predispositions from their parents. Responsible breeders screen their breeding dogs for these conditions and make informed mating decisions to reduce the risk passed on to puppies.
No — but it's the strongest tool we have. Diet, exercise, environment, and genetics all contribute to whether a dog develops a condition. When breeders use the right tests to identify risk in potential parents, the likelihood of many conditions appearing in the puppies drops significantly.
There's no one-size-fits-all here. For the Shetland Sheepdog we track 5 mandatory tests plus 11 additional recommended ones. The specific tests and passing thresholds are detailed further below.
Keep in mind
Reliable screening tests still don't exist for many hereditary conditions, and tests for complex polygenic conditions are not always predictive of severity in the puppies. Even so, they're a powerful tool used by every responsible breeder.
There are two main types of health tests:
Screen the dog's DNA for known disease-causing mutations. Can be performed from puppyhood and give a binary result (clear / carrier / affected).
Clinical and imaging exams like X-ray, ultrasound, or ophthalmoscopy. They show how a predisposition actually manifests — usually only conclusive after 12–18 months.
We group breeding programs into three levels based on testing depth. Ask your breeder directly which level they meet.
A breeder at the Great level performs all mandatory tests plus 11 additional clinically recommended screenings that reduce risk in this breed.
In addition to mandatory tests:
Canine cyclic hematopoiesis(GCS)
Andere
This is an inherited bone marrow disorder where the body's production of blood cells, particularly infection-fighting white blood cells, drops drastically at regular intervals. This cyclic drop temporarily leaves the dog's immune system highly vulnerable to infections. The condition is caused by a genetic mutation affecting how stem cells in the bone marrow mature.
DNA · Passing: CARRIER
Microphthalmia
Augen
Microphthalmia is a congenital developmental disorder of the visual system where one or both of a dog's eyeballs are abnormally small. This structural defect occurs during embryonic development and is often accompanied by other eye abnormalities, such as cataracts, which are cloudy areas in the lens of the eye. Because the eyeball itself is underdeveloped, the surrounding eyelids may also appear droopy or misaligned.
Passing: CLEAR
Progressive Retinal Atrophy (PRA)(PRA)
Augen
Progressive Retinal Atrophy (PRA) is an inherited eye disease that affects the retina, which is the light-sensitive layer of tissue at the back of the eye. In this condition, the specialized cells responsible for detecting light, known as photoreceptors, gradually degenerate and die. Because these cells cannot recover or be replaced, the disease slowly but inevitably leads to complete blindness.
Passing: CARRIER
Corneal dystrophy(CD)
Augen und Sehvermögen
Corneal dystrophy is an inherited eye disorder where abnormal, opaque materials like fats or calcium build up in the cornea, which is the clear outer layer of the eye. This accumulation typically affects both eyes and is non-inflammatory, meaning it does not cause immediate swelling or redness. Over time, these deposits can disrupt the smooth surface of the eye.
Augen · Passing: CLEAR
Distichiasis
Augen und Sehvermögen
Distichiasis is an eye condition where extra eyelashes grow from the meibomian glands, which are the oil glands along the edge of the eyelid. These abnormal hairs point inward and rub directly against the cornea, the clear outer surface of the eye. This constant friction causes mechanical irritation and can damage the sensitive ocular surface.
Augen · Passing: CLEAR
Cataract(HC)
Augen und Sehvermögen
A cataract is a progressive clouding of the lens inside the dog's eye, which is the clear structure that focuses light onto the retina at the back of the eye. When the lens becomes cloudy or opaque, it blocks light from entering, gradually impairing the dog's vision. If left untreated, this condition can eventually lead to complete blindness in the affected eye.
Augen · Passing: CLEAR
Hip dysplasia(HD)
Bewegungsapparat
Hip dysplasia is an inherited skeletal disorder where the ball and socket of the hip joint do not fit together properly. Instead of sliding smoothly, the bones rub and grind against each other, wearing down the protective cartilage. Over time, this chronic friction causes joint instability, painful inflammation, and progressive arthritis, which is the gradual wear and tear of the joint.
Roentgen · Passing: FCI Grade C or better
Cryptorchidism
Fortpflanzung
Cryptorchidism is a developmental condition of the male reproductive system where one or both testicles fail to descend normally into the scrotum. Instead, the undescended testicle remains trapped inside the abdomen or in the groin area. This failure to descend is a physical development issue rather than an active illness, but it alters how the reproductive organs develop.
Physisch · Passing: CARRIER
Color Dilution Alopecia (CDA)(CDA)
Haut und Fell
Color Dilution Alopecia is a genetic skin disorder that affects dogs with diluted coat colors, such as blue, fawn, or lilac. It is caused by an abnormal distribution of pigment within the hair shafts, which makes the hair brittle and prone to breaking. This structural weakness leads to progressive hair loss and leaves the skin more vulnerable to irritation.
Haut · Passing: CARRIER
Dermatomyositis(DMS)
Haut und Fell
Dermatomyositis is an inherited, immune-mediated disease where the dog's immune system mistakenly attacks its own skin and underlying muscles, causing chronic inflammation. This condition primarily affects the blood vessels supplying these tissues, leading to tissue damage. It is most frequently diagnosed in Collies and Shetland Sheepdogs.
Haut · Passing: CARRIER
Congenital deafness(CHSD)
Nervensystem
Congenital deafness is a hereditary hearing loss present from birth that affects the inner ear's sensory cells, preventing sound signals from reaching the brain. It is often linked to specific genetic variants, such as those associated with certain coat patterns like merle or piebald, or breed-specific conditions like Early Onset Adult Deafness (EOAD). This genetic defect causes the vital blood supply to the inner ear to fail, leading to the permanent degeneration of the hearing nerve cells.
Physisch · Passing: BILATERAL_HEARING
These levels are a comparison framework, not an official certification. They help compare breeding programs at a glance.
A complete checklist with every mandatory and recommended test plus identity and rearing questions — take it with you.
Open the full checklistFor breeders
Machine-readable mating rules, minimum ages, scoring schemes, and what's required for HonestDog verification — as a printable guide.
Example rule — Merle coat pattern
Both parents must be No Merle-to-Merle breeding or better.
We compile mandatory tests from official breed regulations and veterinary databases — and check every uploaded certificate for authenticity.
L1 = mandatory under breed-club regulations. L2 = recommended or clinically indicated. L3 = lower prevalence. Every assignment carries a source and confidence rating.
VDH breeding regulations, CIDD (University of PEI), OMIA (University of Sydney), curated veterinary input.
Uploaded certificates are AI-extracted and reviewed by our team for authenticity, date, and result.
5 tests are currently mandatory under the relevant breed-club regulations. The most common are Collie eye anomaly (CEA) (CEA), Merle coat pattern (M), Degenerative Myelopathy (DM). Every test must be completed before mating, and the result must fall within the threshold defined by the regulation.
See breeders who have already uploaded their mandatory tests for verification.
View verified breeders