Inhibition of oviducal sperm transport in rabbits immunized against sperm-specific lactate dehydrogenase (LDH-C₄)

Known quantities of spermatozoa were placed directly into the oviducts, via the utero-tubal junction, of rabbits which had been immunized systemically with either Freund's complete adjuvant plus saline (control) or with adjuvant and saline containing sperm-specific lactate dehydrogenase (LDH-C₄; immune). Sperm transport through the oviducts was estimated by determining the percentage of sperm recovered from a flask connected to the fimbriae. An average of 26.1% of inseminated sperm was recovered from control oviducts while only 6.8% of such sperm were recovered from immune oviducts (the difference is significant; P < 0.002). This reduction in sperm transport occurred in the presence of antibody to LDH-C₄ in the oviducal fluid of immune rabbits, and is probably a major factor contributing to the infertility of females immunized against LDH-C₄.