Genetic Detection and Identification of Chlamydophila psittaci in Captive Psittacine Birds in Thailand

Chlamydophilosis is an important, worldwide zoonosis caused by Chlamydophila psittaci. The aim of this study was to detect C. psittaci on choanal and cloacal swabs which were collected from 178 captive psittacine birds (23 different species) from eight provinces in Thailand. ompA gene detection using nested PCR showed that 7.87% (n=14) were positive for C. psittaci. The C. psittaci detection from two site collections (choanal and cloacal swabs) using nested PCR was more sensitive than from one site collection. Most positive samples (n=11) were from asymptomatic adult birds and three other positive birds showing clinical signs were juvenile birds. As a result, the adult birds which showed no clinical signs could be the explanation for the spread of the disease. Nucleotide sequences for all positive samples were identified as genotype A. Most positive samples had identical nucleotide sequences with C. psittaci isolated from humans in Japan (accession number AB468956). This study demonstrated that C. psittaci genotype A could be found in both symptomatic and asymptomatic infections from the captive psittacine birds in Thailand. Therefore, disease monitoring is necessary to prevent and control disease for bird owners and aviculture in general.