Campylobacter fetus is extracellular bacteria of the genital tract of cattle. They cause infertility and abortion, but there is no documented information on the susceptibility of bovine sperm cells to this bacteria. The aim of this present work was to study the effects provoked by Campylobacter fetus subsp. venerealis when in interaction with bovine sperm cells. The bovine spermatozoa were obtained frozen bovine semen pooled from uninfected bulls, and were exposed to living campylobacter over different periods of time. Light microscopy and scanning electron microscopy first revealed a tropism, then a close proximity followed by tight adhesion between these two different cells. A decrease in the spermatozoa motility was observed. Motile bacteria were observed during the next 3 h, this process began with a tight membrane–membrane adhesion. The adhesion between Campylobacter fetus to the sperm cell occurred either by the flagella or by sperm head. Results from this study demonstrated with light microscopy scanning electron microscopy allowed us to characterize some aspects of the interaction of Campylobacter fetus subsp. venerealis and bovine sperm while preserving the cellular and bacterial structure. This ex vivo model might be useful for studies on adhesion and cytopathogenicity of different field strains of Campylobacter fetus.
KEY WORDS: Adhesion; Campylobacter fetus subsp. venerealis; Sperm cells.