- Veterinarians have treated pet ferrets for over 30 years, leading to a better understanding of the diagnostic differentials associated with common signs.
- Ferrets with adrenal gland disease have a normal history until signs appear.
- One of the most common signs of adrenal gland disease in pet ferrets is alopecia.
- Signalment and clinical signs aid in the diagnosis of this disease.
- Adrenal gland disease in ferrets is distinguished from Cushing’s disease in dogs by signs and pathophysiology.
- One or both adrenal glands may be affected.
- Pituitary or hypothalamic involvement is not reported.
- Pathology varies from benign hyperplasia to adenoma to carcinoma.
- On average, the disease is first recognized around 3 years of age.1
- There is no known sex predilection.1
- Based on the author’s clinical experience and reports from colleagues, this disease may affect up to 50% of pet ferrets in the United States.
- Although there is still speculation as to the cause of adrenal gland disease in ferrets, some likely theories have been suggested and investigated.2
- Recent research gives credence to the theory that neutering destroys the negative feedback mechanism that keeps the release of luteinizing and follicle-stimulating hormones in check.
- After a ferret is neutered, this mechanism is interrupted and increased concentrations of compounds induce pathologic changes in the adrenal glands, potentially leading to adrenal gland disease. ther theories include genetic predisposition or exposure to abnormal light cycles leading to abnormal melatonin concentrations.
- Common signs include alopecia, vulvar enlargement, pruritus, and sexual aggression.
- Alopecia typically originates near the proximal tail and progresses distally; it extends along the flanks and ventrum, eventually involving the dorsum.
- Female ferrets commonly exhibit an enlarged vulva, occasionally accompanied by inflammatory discharge.
- Pruritus is commonly reported in both male and female ferrets. Shampoos, other dermatologic preparations, and antiinflammatory medications are ineffective for adrenal gland–induced pruritus.
- Behavior suggestive of sexual aggression includes biting the back of another ferret (eg, to drag it) or biting at the owner’s ankles.
- In male ferrets, prostatic tissue infrequently may become enlarged and cystic as a result of the hormones produced by the adrenal gland.
- An enlarged prostate can impinge on the urethra, leading to stranguria or dysuria that, if untreated, can result in total urinary blockage and subsequent metabolic derangements.
- A rare manifestation of this disease is bone marrow suppression leading to anemia and potentially leukopenia and thrombocytopenia.
- Pruritic ferrets may exhibit erythema secondary to scratching. This is observed most commonly on the skin between the shoulder blades.
- The spleen may be enlarged.
- Enlarged spleen in older ferrets is a common finding but is not known to be associated with adrenal gland disease.
- An enlarged adrenal gland (uncommon) may be palpable.
- Adrenal gland disease is not associated with pain except when male ferrets are unable to urinate.
- In such cases, the pain index can be rather high; urethral patency must be restored and pain medication must be administered.