Chronic onychomycosis has been identified in several individuals of different pinniped species (Arctocephalus pusillus pusillus, Otaria byronia, Halichoerus grypus, and Phoca groenlandica). Generally, one nail of a rear flipper is affected. This is characterized by an enlarged pulpa elevating the dry, thick and fragile nail in each case. Occasionally there is a painful, warm or enlarged corresponding digit. Identification of the fungus has not been possible until now, however fungal hyphae are always present, diagnosed by scrapes and biopsy. In only one instance did an animal have a dermatomycosis where Trichosporon mucoïdes was isolated. Because local and relatively short term (up to 6 months) systemic anti-mycotic treatment for onychomycosis have not helped, long-term treatment was considered. X-rays of the affected flippers were planned in the general check-up of the animals before starting the treatment. Those revealed osteomyelitis of the terminal phalanx in the affected digit and unexpected osteomyelitis of other bones.
A female grey seal (Halichoerus grypus) developed chronic deep bacterial folliculitis and superficial dermatitis (scrapes and biopsies) following recurrent bite wounds on her hind flippers from her pool mates. It was necessary to separate the animal from the others. A radiographic study of her flipper after apparent external healing following antibiotic therapy revealed osteomyelitis of the bones.