What Is Congenital Hypotrichosis?
Hypotrichosis, also called regional alopecia, is the presence of less than normal amount of hair. Both hypotrichosis and alopecia can be congenital or may occur later in the animal’s life. Congenital hypotrichosis is the term used to describe animals born without their normal hair or who experience hair loss within the first month of life.
The disorder has been associated with abnormalities of the female reproductive organs, defects in other structures such as teeth, claws, and eyes, and skeletal defects.2 The hair loss is bilateral and usually affects temples, ears, abdomen, back; in some cases, it can involve the whole body. Alopecia is later followed by darkening and thickening of the skin and seborrhea.
There may be a sex-linked inheritance as males are predominantly affected. However, in young adult Chesapeake Bay Retrievers symmetrical hair loss affects the same areas of the body in male and female dogs. The most frequent causes are hormonal disturbances (increased thyroid function and hyperadrenocorticism), seborrhea, and certain inherited diseases.
Skin tests reveal normal hair follicle density, although follicles are empty or contain keratin debris and fragments of the hair shaft.
Susceptible Dog Breeds
Genetically-linked hypotrichosis has been reported in the:
- German Shepherd
- Cocker Spaniel
- Basset Hound
- Belgian Shepherd
- Bichon Frise
- French Bulldog
- Labrador Retriever
- Lhasa Apso
- Toy Poodle
- Miniature Poodles
- Yorkshire Terrier
There is no treatment, but selective breeding might reduce the occurrence of this condition.
- Cerundolo et al. – Adult-onset Hair Loss In Chesapeake Bay Retrievers: A Clinical And Histological Study – Veterinary Dermatology 16 (1), 39-46
- Danny W. Scott, D.V.M, William H. Miller, V.M.D, Graig E. Griffin, D.V.M. – Muller and Kirk’s Small Animal Dermatology