Chlamydia psittaci is common in a variety of birds usually in sub-clinical state, and it is an important zoonotic agent. Seven genotypes of C. psittaci are known today in various birds (A-F, E/B). The aim of the research was to classify the Israeli isolates of C. psittaci to genotypes, what has not been done so far. Classification of C. psittaci is made following a positive real-time PCR test. A second PCR test is directed towards the gene that encodes the major outer membrane protein (ompA) of the bacterial envelope, before further nucleotide sequencing. In some of the cases the bacteria could be diagnosed only after isolation in fertile eggs of specific pathogen free chickens.
The survey included genotypic classification in events suspicious to Chlamydia, from domesticated birds, pigeons and pet/zoo birds. Clinical signs included lameness, sinusitis, respiratory or nervous signs, embryonic mortality, non-hatching eggs and mortality. Examined organs included liver and spleen, sinus content, trachea and non-hatching eggs. Out of 31 classified Chlamydia, 55% were genotype E, the most prevalent in chickens (70%) and parrots (46%). The other genotypes were divided between B (16%), E/B (16%) and A (13%).
The innovation in this research: 1. Genotypic classification of Chlamydia psittaci strains in Israel is reported for the first time. 2. Chlamydia psittaci was defined as an etiology of lameness and also embryonic mortality in chickens, which are not considered a common host for this pathogen. 3. Chlamydia psittaci in pigeon brain was found as a possible etiology of nervous signs.
