The effect of the oral administration of lactic-acid probiotic bacteria on the vaginal microflora of bitches.

Introduction: In recent years, probiotics have been increasingly used in companion animals. However, there are few studies on their effect on canine vaginal flora. The objective of this study was to evaluate the effect of orally administrated multi-strain lactic-acid probiotic bacteria on the vaginal flora of healthy bitches.

Material and methods: A total of 38 Labrador retriever bitches were given one sachet of multi-strain probiotic with food once a day for nine weeks. Samples for microbiological examination were taken twice (on day 0 and day 63) from the cranial vagina and cultured for aerobic and anaerobic bacteria.

Results: Bacterial growth was found in 84.2% of the samples on day 0 and in 94.7% of the samples on day 63. Mixed cultures were found in 63.1% of bitches with positive bacterial tests on day 0 and in 73.6% on day 63, and contained a mean 1.8 bacterial strains. An increase in the prevalence of E. coli, Gram-negative rods other than E. coli, Staphylococcus spp. and Streptococcus spp./ Enterococcus spp. was noted after nine weeks (P < 0.05). After the oral administration of the lactic-acid probiotic bacteria, potentially pathogenic Clostridium perfringens, Canicola haemoglobinophilus and Pseudomonas aeruginosa were not isolated. The prevalence of Streptococci other than Streptococcus canis was significantly higher after the administration of the probiotic (26.3% vs 5.3%, P < 0.05), and Enterococcus spp. were isolated in the samples of 28.9% of bitches. There was no increase in the prevalence of Lactobacillus spp.

Conclusion: The results indicate a beneficial effect of oral lactic-acid probiotic bacteria on the composition of vaginal flora in bitches; however, further research is needed.