Effects of seminal vesicle removal on fertility and uterine sperm motility in the house mouse.

The relative significance of the accessory glands of the male reproductive tract in fertility is unclear. To clarify the role of the seminal vesicles, fertility and uterine sperm motility were determined before and after removal of seminal vesicles in the house mouse. After removal of seminal vesicles, the pregnancy rate (number of females pregnant/number of females X 100) was reduced and the time to birth was increased, while the average litter size was not changed. Fertilization, determined by examining the oocytes 30 h after mating, was highly variable after matings with males whose seminal vesicles were removed; in some cases none of the oocytes were fertilized. The motility of sperm recovered from the uterus 1 h after matings with males before and after seminal vesicle removal and sham operations was analyzed using a videomicrographic system. The motility of uterine sperm was less progressive with more lateral displacement of the head about the trajectory and a less linear trajectory after removal of the seminal vesicles. Sham-operated animals showed no consistent changes in motility of uterine sperm. The changes in sperm motility could contribute to the reduction in fertilization since sperm motility is necessary for transport in the female reproductive tract and interaction with the oocytes.