Yarmouth Veterinary Center

75 Willow Street
Yarmouth , ME 04096



Guinea Pigs - Dermatophytosis (Ringworm)

Dermatophyosis (ringworm) is a fungal infection of the surface layers of the skin and hair. It is most commonly caused by Trichophyton or Microsporum species of fungus.

Dermatophytosis is usually diagnosed in young gps.
Itchy, circular areas of hair loss and crusty, scabbed skin usually appear on the head first, and then spread to the body and legs.
Some guinea pigs carry the fungus but have no signs; they are capable of spreading it to other gps.

Risk Factors
GPs with the following conditions are at most risk of developing ringworm:
- immune suppression, eg, with stress
- inadequate vitamin C levels
- young gps
- pregnancy
- exposure to an infected guinea pig
- high environmental temperature and humidity

Differential Diagnosis (other possible causes of the same signs):
- stress
- nutritional deficiency, especially inadequate vitamin C
- cystic ovaries
- diabetes
- low thyroid hormone levels
- parasites - mites, lice
- bacterial infection
- allergy
- cancer

The diagnosis of dermatophytosis is usually made with a combination of physical exam, microscopic exam of skin and hair samples, and fungal culture of hair and skin scrapings.

Affected gps should be isolated until treatment is completed, as indicated by one or two negative cultures.
Dietary deficiencies should be corrected; most importantly, vitamin C must be appropriately supplemented.
Topical products, such as medicated lotions, dips and wipes, may be effective in treating gps that have one or two localized lesions.
Oral antifungal medication is necessary for gps that have more than one or two lesions, or when a more rapid resolution to the problem is desirable.
Isolation and treatment should continue for a minimum of 4 weeks. Ideally, resolution of the problem is confirmed with one or two negative cultures.

Dermatophytosis can spread from infected animals to people.