Hereditary Eye Problems

Health Testing – Miniature Schnauzers

Eye Conditions

‘Congenital Hereditary Cataracts’ (CHC), ‘Hereditary Cataracts’ (HC) & Generalised Progressive Retinal Atrophy (PRA), can occur in the Miniature Schnauzer. Until DNA tests are available to help eradicate these conditions from the breed, caring breeders must eye-test any dog or bitch used in a breeding programme and screen every litter. This is now a mandatory requirement for our Club members. Testing is undertaken by a veterinary ophthalmologist registered with the British Veterinary Association/Kennel Club (BVA/KC) Eye Scheme Panel (www.bva.co.uk)

When looking for a puppy, any caring and responsible breeder will be happy to show you Eye Test Certificates of the mother (dam) & sire confirming they are ‘clinically unaffected’ (eye tested within the previous 12 months). You would also see the Litter Screening Form (LTS) proving the litter is clear of one of the eye conditions (CHC) at time of collection.

When should we Eye Test?

Congenital Hereditary Cataract (CHC): Puppies must be eye-screened for CHC, by a BVA/KC Eye Scheme panellist, between 5 & 8 weeks & before they leave the breeder. A copy of the LSF should be provided to the new owner.

Annual eye testing is necessary to identify HC or PRA, as both conditions develop later.

Hereditary Cataract  (HC) – sometimes referred to as ‘Juvenile’ or, in the USA, as ‘CJC’ – can only be diagnosed from about 6 months onward, and sometimes even later than aged 2 years. All Dogs must be eye-tested prior to breeding.

Generalised Progressive Retinal Atrophy (PRA) may not appear until 12 months upwards, but may be detected in some breeds at any point between 6 months and 6 years. The earliest reported case in Miniature Schnauzers was in a 3-year old.

To summarise: all Miniature Schnauzers should be eye-tested before being bred from, and then annually, whilst used in any breeding programme, irrespective of age

The Need to Eye Test regularly

Because there is, as yet, no DNA test for these conditions, it’s imperative that all Miniature Schnauzers, especially those used for breeding, are checked annually, up to about 8 years of age, by a BVA/KC Eye Scheme panellist. Your breeder or Vet can give you more details & the name of your closest BVA Eye Panellist can be found on www.bva.co.uk.

What should I do if my Dog has problems?

If your dog is diagnosed with CHC, HC or PRA or any other hereditary condition, it’s so important for Miniature Schnauzers for you to tell the Miniature Schnauzer Club (MSC), Northern Schnauzer Club (NSC) or The Schnauzer Club of Great Britain (SCGB) as well as your breeder. You would help even further by completing our Health Survey form on-line at www.schnauzerhealthsurvey.org.uk.

Why should we tell anyone?

Things occur even in the most carefully planned breeding programmes. Only by sharing such vital information will we be able to work towards eradicating these problems from our breed. It’s essential to tell the owners of the sire and dam, because they should not be bred together again. It’s equally important to owners of other puppies in the litter, because great care will be needed if any were used for breeding.

Why hasn’t a solution been found yet?

Because of the unknown mode of inheritance, (thought to be ‘recessive’) it’s not possible to identify dogs which carry the defective gene. Eye testing is the one positive action that caring breeders take, and if owners of affected dogs advise other owners, through the 3 breed clubs, then alternative breeding can be followed.

The Animal Health Trust (AHT) is currently working on CHC, part funded by the Joint Miniature Schnauzer Eye Fund (JMSEF), aimed at finding a DNA test to identify the gene(s) which cause this condition. Work has yet to commence for HC or PRA, although projects for these conditions in other breeds may help locate a solution for Miniature Schnauzers.

What are the Breed Clubs doing?

The 3 clubs responsible for Miniature Schnauzers (MSC NSC & SCGB) support the BVA/KC Eye-Testing Scheme, organise low-cost eye-testing sessions and help raise funds, through JMSEF, to assist research with the AHT.                                                        April 2017