Abstract
BACKGROUND: Little is known about the impact of babesiosis on semen quality and fertility in dogs. CASE PRESENTATION: Four cases of infertility in male dogs after infection with Babesia canis are described. In all dogs sperm quality was low. Two dogs were castrated pharmacologically or surgically. In two dogs fertility was restored after supplementation with selenium and Vitamin E. As possible causes of spermatogenesis disorders due to the treatment of infection with Babesia canis with imidocarb, fever and disturbed testicular microcirculation are discussed. CONCLUSIONS: These cases indicate that if males have fertility problems, question about babesiosis infection in the past should be a permanent point in the clinical interview.