Vaginal flora of the bitch : a retrospective data analysis

Knowledge of the physiological vaginal flora of the bitch is crucial to reduce the prophylactic (over-)use of antibiotics before mating. The vaginal flora of the bitch was already described previously in several studies, usually from small groups of dogs. This study describes a large cohort for the first time. Vaginal swabs submitted to 3 commer-cial laboratories for bacteriological analysis between 2015 and 2021 were analysed retrospectively. Swabs were cultured for aerobic bac-teria and identified by the growth on selective agar plates, biochemi-cal parameters and the use of MALDI-TOF- MS. A total of 22,074 samples were analysed and 351 bacterial species were identified. In the majority of samples, colonization with two or more isolates was found; monoculture was observed, but less common. The most frequently identified isolates were Escherichia coli, Staphylococcus pseudintermedius, β- hemolytic (hem.) streptococci, Pasteurella spp. and α- hem. streptococci. Besides those, also typical nosocomial pathogens, such as Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus spp., were identified in some vaginal samples. The results confirm earlier studies about the bacterial species identified in vaginal swabs, however, for the first time on a large population. Besides, typical nosocomial pathogens known to cause hospital- associated infections were found indicating a possible role of dogs as hosts for multi-resistant pathogens. A major limitation is the lack of details, namely whether samples were collected from healthy or diseased animals. Further studies should include these aspects as well as corresponding fertility to gain further insights.