Screening for Chlamydiaceae in Eurasian lynx (Lynx lynx) reveals a case of ocular infection

Bacteria from the family Chlamydiaceae can cause asymptomatic, persistent infections in humans and animals, but they may also lead to clinical syndromes of varying severity. The actual impact of these infections on the overall health of wildlife populations remains unclear. In the context of conservation translocations, identifying asymptomatic carriers may be particularly important to prevent pathogen introduction into vulnerable or genetically bottlenecked populations. The aim of this study was to investigate ocular Chlamydiaceae infection in free-ranging Eurasian lynx ( Lynx lynx ). Ocular swabs were collected from 34 free-ranging Eurasian lynx originating from Romania (n = 21), Slovakia (n = 7), and Croatia (n = 6), representing both the Carpathian and Dinaric populations. Chlamydiaceae DNA was detected using quantitative PCR targeting the 23S rRNA gene, while species identification was performed by amplification and sequencing of the pmp9 gene. Chlamydiaceae DNA was detected in one sample (2.9%), and sequence analysis confirmed the presence of C. felis . The positive sample originated from a clinically healthy adult male lynx captured in Romania for conservation translocation. Mild unilateral blepharospasm and seromucous discharge that developed four days after capture were misinterpreted as a consequence of handling and were not treated. Screening for other major feline pathogens yielded negative results. This is the second documented case of C. felis -associated ocular infection in Eurasian lynx. Although the observed prevalence was low, the findings emphasize the value of pathogen surveillance during conservation translocations and support the inclusion of testing for Chlamydia spp. in health-screening protocols for Eurasian lynx.