ISSN 2398-2950      

Deafness: congenital (hereditary)

ffelis

Introduction

  • Hereditary deafness.
  • Rare. Estimated as 1% of white cats affected.
  • Cause: autosomal dominant gene.
  • Associated with coat color (white) and blue irises.
  • Signs: bi- or unilateral deafness.
  • Diagnosis: signs, Brain stem auditory evoked response (BAER).
  • Treatment: none.
  • Prognosis: guarded, although unilaterally deaf animals may appear normal.
    Print off the owner factsheet Living with a deaf cat  Living with a deaf cat to give to your client.

Pathogenesis

Predisposing factors

General

  • Genotype of parents.
  • Genotype of offspring.
  • Breed.

Pathophysiology

  • One gene for color is linked to deafness in cats.
  • Autosomal dominant gene for coat color W (white).
    Note: not the same as albino.
  • Homozygous offspring are white and may have blue eyes and deafness.
  • Are not blind/sterile as in dogs.
  • More cats with two blue eyes are deaf than with one blue eye.
  • The genes for blue eyes and deafness have incomplete dominance.
  • Affects longhair cats more severely.
  • A second gene is for coat color piebald (S). Unlike dogs this does not appear to be connected to deafness.
  • Some white cats have a gene for Siamese dilution pigment. These are blue-eyed but not deaf (may explain why fewer purebred cats are deaf than crossbred).
  • Neonatal kittens   →   absence of melanocytes (function unknown) in stria vascularis of cochlea   →   degeneration of stria vascularis   →   degeneration of hair cells of cochlear ducts   →   sensorineural deafness.

Timecourse

  • Degeneration of inner ear structures completed by 3-4 weeks old.

Diagnosis

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Prevention

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Strain G M (1999) Congenital deafness and its recognition. Vet Clin North Am Small Anim Pract 29 (4), 895-907 PubMed.
  • Strain G M (1996) Aetiology, prevalence and diagnosis of deafness in dogs and cats. Br Vet J 152 (1), 17-36 PubMed.
  • Strain G M (1991) Congenital deafness in dogs and cats. Compend Contin Educ 13 (2), 245-50 VetMedResource.

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!

 
 
 
 

To show you are not a Bot please can you enter the number showing adjacent to this field

 Security code