Molecular detection of Chlamydophila felis from conjunctiva of cats infected with conjunctivitis and upper respiratory disease.

Abstract

Background: Chlamydiae are obligate generally Gram-negative intracellular parasites with bacterial characteristics, including a cell wall, DNA, and RNA, and the main characteristics of infections are ocular conjunctivitis and upper respiratory disease.

Aim: The aim of this study was to investigate the prevalence of Chlamydophila infection in a population of shelter cats in Baghdad.

Methods: Molecular detection was done using a polymerase chain reaction (PCR) approach. Fifty shelter cats of various ages, sexes, and breeds participated in the study from 1/11/2023 to 1/4/2024. DNA was extracted and amplified using PCR.

Results: The study's findings revealed that the PCR technique showed that 22/44% of positive cats from a total of 50 cats were assured for the 23S rRNA gene and yielded a band at 400 bp, and for 41/27.3%, these findings are regarded as distinctive for the genus Chlamydophila and positive sample 30/20% from a total of 150 samples was assured for Chlamydophila felis, a band at 680 bp. The findings revealed that the prevalence of Chlamydophila in upper respiratory tract infections in female cats older than 1 year was between 14/50 (28%) and 13/50 (26%) conversely, and the infections exhibited greater prevalence and a higher rate of detection in male under 1 year of age. The present investigation highlighted a significant prevalence of Chlamydophila in respiratory swabs obtained from Persian and Himalayan cats, but Scottish and British cats exhibited a comparatively lower rate of positive Chlamydophila.

Conclusion: In conclusion of this study, a significant number of cats are infected with C. felis, and PCR provided rapid and sensitive detection of Chlamydophila species in different samples and detected Chlamydophila that did not grow in culture. It was considered the first study for the detection of C. felis from conjunctivitis in shelter cats in Baghdad.