Health Testing Guide
Which tests are mandatory, how to spot responsible breeders — and what it costs when things go wrong.
For the Sussex Spaniel we have compiled 2 mandatory and 2 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 Sussex Spaniel suffers from a very small breeding pool, which increases genetic risks within the population. Hip dysplasia (HD) and various hereditary eye conditions are the breed's most well-known weaknesses, though mandatory health tests do exist for these. Prospective buyers should be particularly meticulous in checking the test results of the parent dogs to avoid any unpleasant surprises.
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 Sussex Spaniel we track 2 mandatory tests plus 2 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 2 additional clinically recommended screenings that reduce risk in this breed.
In addition to mandatory tests:
Retinal Dysplasia(RD)
Augen
Retinal dysplasia is a congenital condition affecting the eyes, where the retina (the light-sensitive tissue at the back of the eye) does not develop properly during growth in the womb. This abnormal development leads to structural defects like folds or gaps in the retinal layers. Because the retina is responsible for sending visual signals to the brain, these imperfections can impair normal vision.
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
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 — Ocular anomalies
Both parents must be Clear of hereditary eye diseases 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.
2 tests are currently mandatory under the relevant breed-club regulations. The most common are Ocular anomalies, Hip dysplasia (HD). 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