Open AccessChlamydiae in Free-Ranging and Captive Frogs in Switzerland
Author(s) -
C. E. M. Blumer,
Dieter R. Zimmermann,
R. Weilenmann,
Lloyd Vaughan,
Andreas Pospischil
Publication year - 2007
Publication title -
veterinary pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.794
H-Index - 89
eISSN - 1544-2217
pISSN - 0300-9858
DOI - 10.1354/vp.44-2-144
Subject(s) - chlamydiae , biology , chlamydia , chlamydophila pneumoniae , chlamydiales , microbiology and biotechnology , histopathology , polymerase chain reaction , immunohistochemistry , pathology , medicine , immunology , gene , genetics
A total of 210 frog samples originating either from a mass mortality (1991/1992) or from routine postmortem investigations of the years 1990 to 2004 were examined retrospectively for a possible involvement of Chlamydiae. For a prevalence study of Chlamydia in a selected Swiss amphibian population, 403 samples from free-ranging Rana temporaria were examined. Histopathology, immunohistochemistry using a monoclonal antibody against chlamydial lipopolysaccharide, and a 16S rRNA polymerase chain reaction (PCR) followed by DNA sequencing were performed on the formalin-fixed and paraffin-embedded tissues. Using PCR, 8 of 54 (14.8%) frog samples from the mass mortality (1991/1992) were positive for Chlamydia suis S45. A control group of healthy Xenopus laevis had 3 of 38 positive samples, sequenced as C suis S45 (2/3) and an endosymbiont of Acanthamoeba species UWE1 (1/3). Chlamydophila pneumoniae TW-183 was detected from exotic frogs kept in a zoo. Of the frogs collected for the prevalence study, 6 of 238 (2.5%) tested positive, 1 each for C suis S45, Cp pneumoniae TW-183, and uncultured Chlamydiales CRG22, and the remaining 3 revealed Chlamydophila abortus S26/3. In immunohistochemistry, there were 2 positive labeling reactions, 1 in intestine and the other in the epithelium coating the body cavity, both testing positive for Cp pneumoniae TW-183 in PCR. Histologically there were no lesions recorded being characteristic for Chlamydia. Although there is a prevalence of Chlamydia in Swiss frogs, no connection to a mass mortality (1991/1992) could be established. For the first time, C suis S45 and Cp abortus S26/3 were detected in frog material.