Health Testing Guide
Which tests are mandatory, how to spot responsible breeders — and what it costs when things go wrong.
For the Biewer Terrier we've compiled 5 tests required by Verband Deutscher Kleinhundezüchter e.V. and 4 additionally recommended tests, drawn from breed-club regulations, the University of PEI (CIDD), and OMIA — weighted by severity and heritability.
View verified breedersWhat this grade means
The Biewer Terrier has several breed-typical problems: Although only a few diseases are documented, they include serious conditions such as subacute necrotizing encephalopathy / Leigh syndrome (SNE), primary lens luxation (PLL), progressive rod-cone degeneration (PRCD), and chondrodystrophy (CDDY). Genetic tests are available for all four, and the Verband Deutscher Kleinhundezüchter e.V. mandates them for breeding approval, alongside an examination for patellar luxation (PL 0). A health-conscious breeder will additionally test for portosystemic shunt and Legg-Calvé-Perthes disease (LCPD). Before buying a puppy, ask to see the PL findings and genetic test results of both parents; a PLL carrier may only be bred to a clear partner.
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 Biewer Terrier, Verband Deutscher Kleinhundezüchter e.V. requires 5 tests for breeding approval, plus 4 additional recommended tests. 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 don't always predict severity in the puppies. Even so, they're a powerful tool of responsible breeding.
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 meets the Good level and performs 4 additional clinically recommended screenings that reduce risk in this breed.
In addition to Good:
Legg-Calvé-Perthes disease(LCPD)
Bewegungsapparat
Legg-Calvé-Perthes disease is a serious orthopedic condition affecting the hip joint, primarily in small breed dogs. It occurs when the blood supply to the head of the thigh bone, known as the femur, is spontaneously disrupted. Without blood, this bone tissue dies and collapses, leading to severe joint inflammation and pain.
X-ray · Passing: normal
Degenerative Myelopathy(DM)
Nervensystem
Degenerative Myelopathy is a progressive disease of the spinal cord where the protective sheath around the nerves slowly breaks down. This deterioration disrupts the vital communication signals between the brain and the muscles of the hind limbs. Over time, this lack of signal transmission leads to a complete loss of muscle control in the back legs.
DNA test · Passing: clear or carrier
Hyperuricosuria(HUU)
Nieren
Hyperuricosuria is an inherited metabolic disorder affecting the renal system, specifically how the kidneys process uric acid. Due to a genetic mutation, excess uric acid is excreted into the urine rather than being broken down. This high concentration can cause the acid to crystallize, leading to the formation of painful bladder or kidney stones, also known as uroliths.
Body-fluid analysis · Passing: clear or carrier
Portosystemic hepatic encephalopathy(PSS)
Stoffwechsel
This is a neurological condition caused by liver dysfunction, typically occurring when abnormal blood vessels bypass the liver. Because the liver cannot filter toxins from the bloodstream, these harmful substances build up and directly affect the brain. This lack of proper filtration leads to central nervous system dysfunction.
Passing: normal
These levels are a comparison framework, not an official certification. They help compare breeding programs at a glance.
A complete checklist with every core-standard and additionally 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 — Patellar Luxation
Both parents must be PL 0 or better.
We take mandatory tests from official breed regulations, build the recommended health standard from veterinary databases — and cross-check every uploaded certificate against the dog's profile using AI.
L1 = core standard: the club's required tests where its rules set them, otherwise the recommended health standard for the breed. L2 = additionally 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 read by AI and checked for date, result, and consistency with the dog's profile — our team reviews anything inconclusive.
The Biewer Terrier is not currently listed in our extreme-breeding overview. That does not mean it is free of hereditary disease: which ones are typical, and which tests the parents should have, is on this page.
Self-check
Answer 6 quick questions about your everyday life and see how well the Biewer Terrier fits you — including an honest cost estimate per month, per year, and across the dog's lifetime.
See breeders who have already uploaded their health test results for verification.
View verified breeders