Loading health guide
Health Testing Guide
Which tests are mandatory, how to spot responsible breeders — and what it costs when things go wrong.
For the Frenchton we have compiled 6 mandatory and 20 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 Frenchton results from crossing two brachycephalic breeds (French Bulldog and Boston Terrier). Because anatomical risks such as Brachycephalic Obstructive Airway Syndrome, ectropion/entropion, or spinal malformations are carried by both parent breeds, this crossbreed provides little to no health relief regarding respiration and the musculoskeletal system. Eye conditions such as cataracts and lens luxation are also among the primary risks. Health-focused breeding therefore relies on comprehensive screening of parent animals for respiratory function, spinal changes, and eye diseases to systematically minimize risks.
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 Frenchton we track 6 mandatory tests plus 20 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 20 additional clinically recommended screenings that reduce risk in this breed.
In addition to mandatory tests:
Apple head
Allgemeine Fitness und Anatomie
Apfelkopf, or apple head, describes an extremely rounded, dome-like skull shape with a very pronounced forehead angle, or stop. This skeletal variation affects the structure of the head and can predispose dogs to open fontanelles, which are soft spots where the skull bones fail to close fully. In some cases, this shape can also restrict fluid flow in the brain, leading to a buildup of fluid known as hydrocephalus.
Physisch
Cleft palate
Allgemeine Fitness und Anatomie
A cleft palate is a congenital birth defect where the roof of the mouth fails to fuse properly during development in the womb. This failure leaves an abnormal opening between the oral cavity and the nasal passages. Because these two systems are directly connected, food, liquids, and air cannot be properly separated during swallowing.
Physisch
Histiocytic ulcerative colitis(HUC)
Andere
Histiocytic ulcerative colitis is a severe, chronic inflammatory disease of the large intestine, or colon. It occurs when specific bacteria invade the lining of the intestinal wall, triggering an abnormal and intense immune response. This leads to deep inflammation and painful ulcers in the colon.
Koerperfluessigkeiten
Tracheal hypoplasia
Atmung
This is a congenital respiratory condition where the dog's windpipe, or trachea, is abnormally narrow from birth. The rings of cartilage that normally keep the windpipe open are malformed, which restricts the flow of air to the lungs. This makes it significantly harder for the dog to breathe normally.
Roentgen
Keratoconjunctivitis sicca (KCS) - "dry eye"(KCS)
Augen
Keratoconjunctivitis sicca (KCS), commonly known as dry eye, is a chronic disease of the ocular system where the tear glands fail to produce enough natural tears. Without this protective moisture, the cornea (the clear surface of the eye) and surrounding tissues become dry, inflamed, and highly susceptible to painful damage.
Augen
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
Third eyelid (nictitating membrane) abnormalities - "cherry eye"
Augen und Sehvermögen
A prolapse of the nictitating membrane gland, commonly called 'cherry eye,' occurs when the tear gland of the third eyelid slips out of its normal position. This gland is responsible for producing a significant portion of the eye's protective tear film. When the connective tissue holding it in place weakens, the gland protrudes, appearing as a red, fleshy mass in the inner corner of the eye.
Physisch
Primary Open-Angle Glaucoma(POAG)
Augen und Sehvermögen
Primary open-angle glaucoma is an inherited eye disease where the natural fluid inside the eye cannot drain properly. This fluid buildup causes a gradual increase in pressure within the eyeball, which eventually damages the optic nerve, the connection between the eye and the brain. Without management, this pressure leads to permanent blindness.
Augen
Complex vertebral malformation(CVM)
Bewegungsapparat
Complex vertebral malformation is a congenital condition where the bones of the spine, known as vertebrae, do not develop properly during fetal growth, sometimes resulting in abnormally shaped bones like "butterfly vertebrae." This structural defect affects the skeletal system and can put pressure on the spinal cord, which is the main nerve pathway running down the back.
Roentgen
Patellar Luxation(PL)
Bewegungsapparat
Patellar luxation, also known as a luxating patella, is a physical condition affecting the knee joint where the kneecap slips out of its normal groove. This misalignment interferes with the mechanical movement of the hind leg and can cause the joint to lock. Over time, this abnormal friction can lead to painful joint wear and tear, known as osteoarthritis.
Physisch
Atopy(CAD)
Haut und Fell
Atopy is a chronic allergic skin disease where a dog's immune system overreacts to common environmental substances like pollen, mold spores, and dust mites. This inappropriate immune response damages the natural protective barrier of the skin, leading to persistent inflammation and irritation. It primarily affects the skin, which is the body's largest organ system.
Haut
Demodicosis / Demodectic mange
Haut und Fell
Demodicosis is a skin disease caused by an overgrowth of microscopic Demodex mites that naturally live inside a dog's hair follicles. While these mites are normally harmless, an inherited or acquired weakness in the immune system can allow them to multiply uncontrollably. This overgrowth leads to inflammation and damage to the skin barrier.
Haut
Fold dermatitis/pyoderma
Haut und Fell
Fold dermatitis, also known as intertrigo, is an inflammatory skin condition that occurs within deep skin folds. When skin rubs against skin, it traps moisture, heat, and debris, creating an ideal environment for bacteria and yeast to overgrow. This leads to localized skin infections, particularly in breeds with pronounced facial, lip, or tail folds.
Physisch
Pattern baldness
Haut und Fell
Pattern baldness is a cosmetic, genetically influenced condition affecting the skin and coat. It occurs when hair follicles gradually shrink over time, leading to localized hair loss. Because there is no underlying inflammation or infection, the skin itself remains healthy and unaffected.
Haut
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
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
Intervertebral disc disease(IVDD)
Nervensystem
Intervertebral Disc Disease (IVDD) is a degenerative condition affecting the spine, where the cushioning discs between the vertebrae harden and rupture. When these discs herniate, meaning they bulge or burst, they press against the spinal cord and surrounding nerves. This compression disrupts the nervous system, causing pain and potentially blocking signals between the brain and the limbs.
Hydrocephalus
Nervensystem
Hydrocephalus is a neurological condition affecting the brain and nervous system, commonly referred to as water on the brain. It occurs when cerebrospinal fluid, the natural protective liquid surrounding the brain, builds up abnormally inside the brain's cavities, known as ventricles. This accumulation creates harmful pressure on the surrounding brain tissue, which can impair normal brain function.
Roentgen
Pyloric stenosis
Verdauung und Darm
Pyloric stenosis is a narrowing of the pylorus, which is the muscular valve that regulates the passage of food from the stomach into the small intestine. This narrowing obstructs the digestive system by preventing food from entering the intestines normally. It is typically a congenital condition, meaning dogs are born with it.
Ultraschall
Cranioschisis
Zähne und Knochen
Lückenschädel is a congenital developmental defect affecting the skeletal system, specifically the skull. It occurs when the bones of the cranial vault fail to harden or ossify completely, leaving thin spots, depressions, or actual gaps in the bone structure. This defect is often associated with increased pressure within the skull and other brain abnormalities.
Roentgen
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 — Brachycephalic obstructive airway syndrome (BOAS)
Both parents must be tested for Brachycephalic obstructive airway syndrome (BOAS) and show a passing result.
We compile mandatory tests from official breed regulations and veterinary databases — and cross-check every uploaded certificate against the dog's profile using AI.
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 checked for date, result, and consistency with the dog's profile — with our team reviewing anything inconclusive.
6 tests are currently mandatory under the relevant breed-club regulations. The most common are Brachycephalic obstructive airway syndrome (BOAS) (BOAS), Ectropion / Entropion, Retinal Dysplasia (RD). 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