title: Aeromonas sobria, a causative agent of disease in farmed perch, Perca fluviatilis L.
abstract: Significant numbers of perch, Perca fluviatilis, raised on a pilot fish farm in Switzerland presented focal skin lesions on the lateral sides and fin rot. Mortality rates reached levels of up to 1% of the total fish on the farm per day. Virtually pure cultures of Aeromonas sobria were isolated from the liver, kidney, spleen and skin lesions of affected fish. Aeromonas sobria isolated from the farmed perch had a haemolytic effect on sheep and trout erythrocytes, autoaggregated, was cytotoxic for cultured fish cells and possessed genes involved in type III protein secretion. Experimental infection of naive perch with a single colony isolate of A. sobria from an affected farm fish resulted in the development of clinical signs identical to those seen on the farm. The results indicate that A. sobria can act as a primary pathogen of perch.
authors.affiliation: Centre for Fish and Wildlife Health, Institute of Animal Pathology, University of Berne, Berne, Switzerland. thomas.wahli@itpa.unibe.ch
authors.forename: T
authors.initials: T
authors.lastname: Wahli
authors.forename: S E
authors.initials: SE
authors.lastname: Burr
authors.forename: D
authors.initials: D
authors.lastname: Pugovkin
authors.forename: O
authors.initials: O
authors.lastname: Mueller
authors.forename: J
authors.initials: J
authors.lastname: Frey
mesh_terms: D000333:Aeromonas / Q000235:genetics / Q000472:pathogenicity*; D000595:Amino Acid Sequence; D000818:Animals; D017756:Aquaculture; D003601:Cytotoxicity Tests, Immunologic; D017931:DNA Primers; D004586:Electrophoresis; D005393:Fish Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology*; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000473:pathology / Q000662:veterinary*; D006461:Hemolysis / Q000502:physiology; D007668:Kidney / Q000382:microbiology; D008099:Liver / Q000382:microbiology; D010471:Perches; D011506:Proteins / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D012867:Skin / Q000382:microbiology / Q000473:pathology; D013045:Species Specificity; D013154:Spleen / Q000382:microbiology; D013557:Switzerland / Q000453:epidemiology; D013696:Temperature
chemical_list: D017931:DNA Primers; D011506:Proteins