Rg. Hewinson et al., DETECTION OF CHLAMYDIA-PSITTACI DNA IN AVIAN CLINICAL-SAMPLES BY POLYMERASE CHAIN-REACTION, Veterinary microbiology, 54(2), 1997, pp. 155-166
A polymerase chain reaction (PCR) assay was developed to detect Chlamy
dia psittaci DNA in faeces and tissue samples from avian species. Prim
ers were designed to amplify a 264 bp product derived from part of the
5' non-translated region and part of the coding region of the ompA ge
ne which encodes the major outer membrane protein. Amplified sequences
were confirmed by Southern hybridization using an internal probe. The
sensitivity of the combined assay was found to be between 60 to 600 f
g of chlamydial DNA (approximately 6 to 60 genome copies). The specifi
city of the assay was confirmed since PCR product was not obtained fro
m samples containing several serotypes of C. trachomatis, strains of C
. pneumoniae, the type strain of C. pecorum, nor from samples containi
ng microorganisms commonly found in the avian gut flora. In this study
, 404 avian faeces and 141 avian tissue samples received by the Centra
l Veterinary Laboratory over a 6 month period were analysed by PCR, an
tigen detection ELISA and where possible, cell culture isolation. PCR
performed favourably compared with ELISA and cell culture, or with ELI
SA alone. The PCR assay was especially suited to the detection of C. p
sittaci DNA in avian faeces samples. The test was also useful when app
lied to tissue samples from small contact birds associated with a case
of human psittacosis where ELISA results were negative and chlamydial
isolation was a less favourable method due to the need for rapid diag
nosis.