title: Epitheliocystis Distribution and Characterization in Brown Trout (Salmo trutta) from the Headwaters of Two Major European Rivers, the Rhine and Rhone.
abstract: We present a first description of the distribution and characterization of epitheliocystis infections in brown trout (Salmo trutta) from the upper catchments of two major European rivers, the Rhine and the Rhone. Overall, epitheliocystis was widely distributed, with 70% of the Rhine and 67% of the Rhone sites harboring epitheliocystis positive brown trout. The epitheliocystis agents Candidatus Piscichlamydia salmonis and Candidatus Clavichlamydia salmonicola could be identified in both catchments, although their relative proportions differed from site to site. Additionally, in two rivers in the Rhine catchment, a new species of Candidatus Similichlamydia was identified. Based on the histology, infection intensity, and severity of pathological changes were significantly more pronounced in mixed chlamydial infections, whereas single infections showed only low numbers of cysts and mild pathology. Infections could be found over a wide range of temperatures, which showed no correlation to infection prevalence or intensity.
authors.affiliation: Department of Infectious Diseases and Pathobiology, Centre of Fish and Wildlife Health, University of Bern Bern, Switzerland.
authors.forename: Maricruz
authors.initials: M
authors.lastname: Guevara Soto
authors.affiliation: Department of Pathobiology, Institute of Veterinary Pathology, University of Zurich Zurich, Switzerland.
authors.forename: Lloyd
authors.initials: L
authors.lastname: Vaughan
authors.affiliation: Department of Infectious Diseases and Pathobiology, Centre of Fish and Wildlife Health, University of Bern Bern, Switzerland.
authors.forename: Helmut
authors.initials: H
authors.lastname: Segner
authors.affiliation: Department of Infectious Diseases and Pathobiology, Centre of Fish and Wildlife Health, University of Bern Bern, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wahli
authors.affiliation: Department of Clinical Research and Veterinary Public Health, Veterinary Public Health Institute, University of Bern Bern, Switzerland.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Vidondo
authors.affiliation: Department of Infectious Diseases and Pathobiology, Centre of Fish and Wildlife Health, University of Bern Bern, Switzerland.
authors.forename: Heike
authors.initials: H
authors.lastname: Schmidt-Posthaus
keywords: Candidatus Clavichlamydia salmonicola; Candidatus Piscichlamydia salmonis; Candidatus Similichlamydia sp.; Switzerland; catchment; epitheliocystis; survey