Algal dermatitis in cichlids.
Three varieties of a popular African cichlid aquarium species, Pseudotropheus zebra, from 2 tropical fish farms in east central Florida were submitted for diagnostic evaluation because of the development of multifocal green lesions. The percentage of infected fish in these populations varied from 5 to 60%. Fish were otherwise clinically normal. Microscopic examination of fresh and fixed lesions confirmed algal dermatitis, with light invasion of several internal organs in each group. A different alga was identified from each farm. Fish from farm A were infected with Chlorochytrium spp, whereas fish from farm B were infected with Scenedesmus spp. Because of the numbers of fish involved, bath treatments to remove the algae from affected fish from farm B were attempted, with different dosages of several common algaecides including copper sulfate pentahydrate, diuron, and sodium chloride. However, none of these treatments were successful, possibly because of the location of the algae under the scales and within the dermis, and also because of the sequestering effect of the granulomatous response. To our knowledge, this is the first report of algal dermatitis in ornamental cichlids, as well as the first report of Scenedesmus spp infection in any fish.
Yanong
Roy P E
RP
Department of Fisheries and Aquatic Sciences, College of Agricultural and Life Sciences, University of Florida, Ruskin 33570, USA.
Francis-Floyd
Ruth
R
Curtis
Eric
E
Klinger
Ruth Ellen
RE
Cichra
Mary E
ME
Berzins
Ilze K
IK
D000818:Animals; D017756:Aquaculture; D000460:Chlorophyta / Q000254:growth & development*; D023681:Cichlids / Q000382:microbiology*; D003872:Dermatitis / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005393:Fish Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D012867:Skin / Q000382:microbiology / Q000473:pathology