title: Treatment of ichthyophthiriasis with photodynamically active chlorophyllin.
abstract: Water-soluble chlorophyll (chlorophyllin) exerts pronounced photodynamic activity on fish parasites. In order to determine its potential as a remedy against ectoparasites in fish carps were incubated in water with defined concentrations of chlorophyllin. The main focus of the experiments was on the ciliate Ichthyophthirius multifiliis (Fouquet) which is responsible for considerable losses in livestock in aquaculture. As malachite green, which in the past efficiently cured infected fishes, is banned because of its possible carcinogenicity; no effective remedy is presently available in aquaculture to treat ichthyophthiriasis. Using chlorophyllin, the number of trophonts was significantly reduced (more than 50 %) after 3 h incubation of infested fish at 2 and 4 mg/L and subsequent irradiation with simulated solar radiation. The lack of reinfection after light treatment indicates that also the remaining parasites have lost their multiplication capacity. In the controls (no chlorophyllin and no light, light but no chlorophyllin, or chlorophyllin but no light), no reduction of the I. multifiliis infection was observed. We propose that chlorophyllin (or other photodynamic substances) is a possible effective countermeasure against I. multifiliis and other ectoparasites in aquaculture.
authors.affiliation: Department of Biology, Cell Biology, FAU, Neue Straße 9, Möhrendorf, Germany. donat@dphaeder.de.
authors.forename: D-P
authors.initials: DP
authors.lastname: Häder
authors.affiliation: Developmental Biology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Schmidl
authors.affiliation: Zoological Institute, University Stuttgart-Hohenheim, Stuttgart, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Hilbig
authors.affiliation: Bavarian State Research Centre for Agriculture, Institute for Fisheries, Starnberg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Oberle
authors.affiliation: Bavarian State Research Centre for Agriculture, Institute for Fisheries, Starnberg, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Wedekind
authors.affiliation: Department of Biology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: P R
authors.initials: PR
authors.lastname: Richter
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000627:therapeutic use*; D017756:Aquaculture; D002347:Carps; D002735:Chlorophyllides / Q000627:therapeutic use*; D016798:Ciliophora / Q000145:classification* / Q000187:drug effects; D016770:Ciliophora Infections / Q000188:drug therapy / Q000469:parasitology / Q000662:veterinary*; D005393:Fish Diseases / Q000469:parasitology
chemical_list: D000891:Anti-Infective Agents, Local; D002735:Chlorophyllides; C007020:chlorophyllin
keywords: Aquaculture; Chlorophyllin; Ectoparasite; Fish; Ichthyophthiriasis; Ichthyophthirius multifiliis; Parasitology; Photochemistry; Photodynamic substance