TWENTY-FOURTH ANNUAL EASTERN FISH HEALTH WORKSHOP Royal Pavilion Resort, Atlantic Beach, NC MARCH 9-11, 1999 Ulcerative Dermatitis In Striped Bass: A Concern Or Problem For The Chesapeake Bay Laurence Pieper¹, Craig Weedon¹, Dr. Ana Baya², and Dr. Eric May³ 1Maryland Department of Natural Resources, Fish Health and Disease Unit; 2Maryland Department of Agriculture, Animal Health Unit; 3Maryland Cooperative Fish and Wildlife Research Unit, University of Maryland Eastern Shore Ulcerative dermatitis syndromes (UDS), or ulcerative dermatopathies, affect the skin of most species of marine, estuarine and freshwater fish. Collectively, the conditions are characterized by the presence of multiple small red sores, which in some cases coalesce to involve the entire body. Ulcerative dermatitis in Chesapeake Bay striped bass was first reported to the Maryland Department of Natural Resources (DNR), Fish Health and Disease Unit in September 1994 by a pound netter harvesting menhaden in the Potomac River. The appearance of this dermatitis along with the return of the striped bass stock in the Chesapeake has created concern among managers who have heard reports of this condition from different user groups. Striped bass were collected monthly in the Maryland portion of the Chesapeake Bay from gill nets, pound nets, and hook and line; to date over 200 fish have been collected for the combined bioenergetics model and health evaluation. Presently, 115 fish have been histologically evaluated to determine the presence or absence of granulomas and microbilogical infections. Ranking of the bacterial granuloma distribution resulted in finding 66/105 fish without granulomas, with 13 of these fish exhibiting external lesions. 13/105 fish received a rank of one, with 6 of these fish having skin lesions. 16/105 were scored as a rank two with 15 exhibiting skin lesions, and 10/105 were scored as a rank three with all having skin lesions. The final preliminary trend seen is that as the severity increases, - i.e. from rank 1 to 3, the percent of fish exhibiting external lesions increase. This would suggest that the fish develop a systemic infection first, and that manifestation as skin lesions is time and severity dependent. Return to 24th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page