The fertilizing capacity ofepididymal spermatozoa in the pig

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\x=req-\ 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 sperma-tozoa from different regions of the epididymis in the domestic pig. Text-fig. 1. Diagram showing the segments into which the boar epididymis was divided. Epididymides were obtained by castrating sexually rested 7-24-month-old German Landrace boars under sodium pentobarbital anaesthesia. Each epididymis was divided into segments (Text-fig. 1). Initially, the segments were the caput, corpus, proximal and distal cauda epididymidis. In subsequent experiments the distal 1 cm of the corpus (Corpus 2), the most proximal (Cauda 1), an