English Cocker Spaniel: inherited diseases and health

Updated 2026-09-30 · 2 sources

Based on: OMIA (University of Sydney), Wikidata

Breed health

The inherited conditions below have been documented in this breed in published research. That does not mean your dog has them or will get them – but it helps to know the names when you talk to a breeder or a vet.

Conditions this breed is prone to

Veterinary charities list this breed as more likely than others to get these conditions. Read the signs and what to do:

English Cocker Spaniel and chocolate: how much is dangerous?

Typical adult weight: 13–14.5 kg. Grams of chocolate at which signs can start (20 mg/kg) and at which severe signs are reported (40 mg/kg):

Dog weight	Milk	Dark 70–85%	Baking / unsweetened
13 kg	130 g signs 260 g severe	32 g signs 65 g severe	19 g signs 37 g severe
14.5 kg	145 g signs 290 g severe	36 g signs 72 g severe	21 g signs 41 g severe

Based on published doses: signs from about 20 mg/kg, severe signs from 40 mg/kg (US FDA, Cortinovis & Caloni 2016, Swedish Poison Information Centre). An estimate, not a diagnosis.

Check the exact amount with the chocolate calculator →

Inherited conditions documented in the breed

Conditions documented: 14

A gene variant is known for 9 of the conditions below, so a DNA test may exist. Ask your vet or the breed club.

Condition	Body system	Inheritance	Gene variant known
Ataxia with isolated vitamin E deficiency^[1]	Vision / eye	Autosomal recessive	Yes
Cardiomyopathy, dilated^[1]	Cardiovascular system	Multifactorial	No
Ciliary dyskinesia, primary, generic^[1]	Respiratory system	–	No
Deafness, generic^[1]	Hearing / vestibular / ear	Multifactorial	No
Distichiasis^[1]	Vision / eye	Multifactorial	No
Glycogen storage disease VII^[1]	Homeostasis / metabolism	Autosomal recessive	Yes
Nephropathy, COL4A4 related^[1]	Renal / urinary system	Autosomal recessive	Yes
Progressive rod-cone degeneration, PRCD-related^[1]	Vision / eye	Autosomal recessive	Yes
Pseudomyotonia, paradoxical, SLC7A10-related^[1]	Muscle	Autosomal recessive	Yes
Retinal atrophy, progressive, CACNA1F-related^[1]	Vision / eye	X-linked recessive	Yes
Retinal dysplasia, NDP-related^[1]	Vision / eye	X-linked recessive	Yes
Tremor, X-linked, PLP1-related^[1]	Nervous system	X-linked recessive	Yes
Xanthinuria, type II^[1]	Renal / urinary system	Autosomal recessive	Yes
XX difference of sexual development, generic^[1]	Reproductive system	Multifactorial	No

What this list means

“Documented in the breed” means at least one published case or study – it says nothing about how common the condition is.
Many of these conditions are rare. A responsible breeder can tell you which health tests the parents have had.
Where the gene variant is known, a DNA test may exist – ask your vet or the breed club.
If your pet shows signs of illness, contact your vet. This page cannot tell you whether your pet is ill.

About the breed

Height: 38–41 cm
Weight: 13–14.5 kg
FCI number: 005

^[2]

If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

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Sources

How this page was made: the list is taken directly from the sources below; nothing on it was written by AI. Names of conditions may be machine-translated. It is information, not a diagnosis. How we write our pages