The fertilizing capacity of epididymal spermatozoa in the pig

Institut für Tierzucht und Haustiergenetik der Universität Göttingen, 34 Göttingen, Albrecht-Thaer-Weg 1, West-Germany In all mammals studied so far, with the possible exception of man, it has been shown that sperm cells emerging from the testis have to pass through at least part of the epididymis before they acquire the ability to fertilize (Bedford, Calvin & Cooper, 1973; Bedford, 1974). The literature regarding the fertilizing capacity of spermatozoa collected from different segments of the epididymis in laboratory animals has been summarized by Paufler & Foote (1968) and Orgebin-Crist (1969). Little information is available for the large domestic species although bulls have been successfully inseminated with spermatozoa from the cauda epididymidis (Lardy & Ghosh, 1952; Barker, 1954; Igboeli & Foote, 1968). The present experiments were therefore conducted to examine the fertilizing capacity of spermatozoa from different regions of the epididymis in the domestic pig. Epididymides were obtained by castrating sexually rested