Prevalence of Chlamydophila abortus infection in domesticated ruminants inTaiwan

This study is to (1) investigate the prevalence of Chlamydophila abortus in fection in cows and goats in Taiwan, and (2) compare the genetic properties of Taiwanese isolates with abortion strains from other sources. Approximat ely 71% of aborted cows and 58% of aborted does had IgG against C. abortus in their sera. 'The seroprevalence rate in cows may be overestimated, becau se a certain degree of cross-reactivity with C. pecorum cannot be ruled out . Only 22.7% (from aborted cows) and 33.3% (from aborted does) of vaginal s wabs that tested positive by polymerase chain reaction led to successful is olation of C. abortus by inoculation into chicken embryos, equivalent to 7. 1% and 7.9% of isolation rates, respectively. The major outer membrane pro tein gene of 15 Taiwanese abortion isolates was compared with that of vario us strains by restriction fragment length polymorphism (RFLP) and nucleotid e sequencing. Restriction enzyme CfoI was able to distinguish Taiwanese rum inant isolates, which have identical RFLP patterns, from C. felis (feline) and C. psittaci (avian) strains. Taiwanese isolates had 98.8-100% homology with known ruminant abortion strains and were phylogenetically closest to b ovine LW508 strain.