Health Testing Guide
Which tests are mandatory, how to spot responsible breeders — and what it costs when things go wrong.
For the Continental Toy Spaniel (Papillon) we have compiled 1 mandatory and 6 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 Papillon is considered a very healthy breed, as there are only a few known breed-specific hereditary conditions. The primary focus is almost exclusively on eye diseases such as Progressive Retinal Atrophy (PRA) and the breed-specific Progressive Retinal Atrophy 1 (PRA-Pap1). Since reliable DNA tests exist for both conditions and are mandatory health tests for breeding, this risk can be effectively managed when purchasing from reputable breeders.
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 Continental Toy Spaniel (Papillon) we track 1 mandatory tests plus 6 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 6 additional clinically recommended screenings that reduce risk in this breed.
In addition to mandatory tests:
Progressive Retinal Atrophy (PRA), CNGB1-related(PRA-CNGB1)
Augen
This is an inherited eye disease where a genetic mutation in the CNGB1 gene causes the light-sensitive cells of the retina at the back of the eye to slowly degenerate. Over time, these photoreceptor cells, which are responsible for capturing light and sending visual signals to the brain, stop functioning and die off. This leads to a progressive and permanent loss of vision in both eyes.
Passing: Clear or Carrier
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: frei / 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
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: Clear or Carrier
Mitral valve dysplasia(MVD)
Herz
Mitral valve dysplasia is a congenital heart defect where the mitral valve, which acts as a one-way gate on the left side of the heart, does not form correctly. This malformation prevents the valve from closing tightly, allowing blood to leak backward instead of pumping efficiently to the body. Over time, this leakage strains the heart muscle, which can lead to heart enlargement and eventual heart failure.
Ultraschall · Passing: NORMAL
von Willebrand's disease(vWD)
Stoffwechsel
Von Willebrand disease is an inherited bleeding disorder that affects the blood's ability to clot properly. It is caused by a deficiency or malfunction of the von Willebrand factor, a specific protein that helps blood platelets stick together to plug damaged blood vessels. Without enough of this functional protein, the clotting process is delayed, which can lead to excessive bleeding even from minor injuries.
Passing: Clear or Carrier
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 — Progressive Retinal Atrophy (PRA), CNGB1-related
Both parents must be Clear or Carrier 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.
1 tests are currently mandatory under the relevant breed-club regulations. The most common are Patellar Luxation (PL). 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