English cocker spaniel: familial nephropathy and kidney screening
The English cocker spaniel carries an inherited kidney disease that is feared precisely because it strikes early: familial nephropathy. A study by Davidson, Bell, Lees, Kashtan, Davidson and Murphy, published in 2007 in the Journal of Veterinary Internal Medicine, identified the causal mutation, a single nucleotide substitution at base 115 of the COL4A4 gene that creates a premature stop codon in exon 3 and disrupts the type IV collagen of the kidney filtration membrane (study on Google Scholar). Inheritance is autosomal recessive: only puppies that receive two copies of the mutation fall ill. Our English cocker spaniel breed page puts this risk into the wider picture of the breed.
Kidney failure in a young dog
Unlike the kidney failure of elderly dogs, familial nephropathy appears in puppies or young adults, often between six months and two years of age. Early signs are vague: the dog drinks and urinates far more, loses weight despite a proper diet, grows less well than its littermates, tires easily, then develops vomiting and lethargy. Protein leaking into the urine is an early marker. Diagnosis relies on blood and urine tests, in particular creatinine, SDMA and the urine protein to creatinine ratio, sometimes completed by a kidney biopsy. There is no cure: only a vet can set out a plan to slow the disease down.
DNA testing of breeding dogs, the only real lever
Because the mutation is known, a simple saliva or blood sample classifies a dog as clear, carrier or affected. Two carriers mated together produce on average one quarter of affected puppies, whereas a carrier mated to a clear dog produces no affected puppy at all. A study by Andrade, Caceres, Trecenti, Borges and Oliveira-Filho, published in 2020 in Veterinary and Animal Science, genotyped 221 English cocker spaniels and found the mutation at an allele frequency of 0.9 %, confirming that it circulates quietly and justifying routine genotyping of breeding stock (study on Google Scholar). Ask the breeder for these written results before reserving a puppy.
A second weak point: progressive retinal atrophy, prcd-PRA
The English cocker spaniel is also among the breeds tested for progressive rod-cone degeneration. A study by Zangerl and colleagues, published in 2006 in Genomics, identified the PRCD gene and showed that an identical mutation causes this retinal degeneration in dogs and retinitis pigmentosa in humans, with complete concordance across the many breeds studied (study on Google Scholar). Here again a DNA test exists and onset is late: night vision fades first, before progressive blindness. An annual eye examination is a useful addition to the routine care described in our dog care and grooming section.
Follow-up costs and insurance
DNA tests cost tens of euros per disease and per dog, a trivial sum next to the price of failing kidneys. An affected young dog needs regular blood and urine work-ups, a therapeutic renal diet, medication and sometimes fluid therapy, so the yearly bill quickly reaches several hundred euros, hospital stays aside. An inherited disease already declared before the policy starts is never covered, which is why a puppy should be insured as soon as it arrives. Compare offers on our English cocker spaniel insurance page and take stock with our guide to pet insurance for dogs, cost and value.
Frequently asked questions
Will a carrier dog become ill?
No. A carrier has a single copy of the mutation and stays clinically healthy for life. It simply must never be mated to another carrier, otherwise affected puppies can be born.
At what age should an English cocker spaniel be screened?
The DNA test can be done in the first weeks of life and only once, ever. For kidney function, blood and urine tests at around one year of age, then at annual visits, help pick up an abnormality early.
Can familial nephropathy be cured?
There is no cure. Management aims to slow progression and preserve comfort, through a renal diet and control of proteinuria and blood pressure, always under veterinary supervision.
This guide is part of Planète Pets’s Dogs universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.