SPERM MALFORMATIONS THROUGHOUT THE BOAR EPIDIDYMAL DUCT

Taking into account the importance of the sperm epididymal maturation process, and the consequential changes in the spermatozoa, we studied eight different sperm malformations in the caput, corpus, and cauda re gions of the epididymis of healthy and sexually mature Landrace boars in order to determine the origin of these sperm abnormalities. Epididy mal sperm characteristics were examined using light microscopy, scanni ng and transmission electron microscopy. The incidence of each type of malformation investigated was established after counts of 10000 sperm atozoa in each of the three epididymal regions. The different sperm ma lformations studied were: (1) spermatozoa with tail folded at the conn ecting piece; (2) spermatozoa with tail folded at the midpiece; (3) sp ermatozoa with tail folded at the Jensen's ring; (4) spermatozoa with tail folded at the principal piece; (5) coiled tail spermatozoa; (6) s permatozoa with two fused tails; (7) macrocephaly; and (8) microcephal y. The count performed in each epididymal region indicated that, where as significant differences (P less than or equal to 0.01) existed betw een the frequencies of some types of sperm malformations and the epidi dymal region from where the sperm originate, other sperm malformations were more uniformly distributed along the epididymal duct. Among the eight different sperm malformations studied, three were found to be of secondary origin: spermatozoa with tail folded at the Jensen's ring ( originated in the epididymal cauda); spermatozoa with coiled tail; and spermatozoa with two fused tails (originated in the epididymal corpus ). Knowing the origin of spermatozoa abnormalities will assist researc h into the study of infertility and reproductive pathology.