MODULATION OF POSTTHAW MOTILITY, SURVIVAL, CALCIUM-UPTAKE, AND FERTILITY OF BOVINE SPERM BY FEMALE GENITAL PRODUCTS

Because the different portions of the female genital tract act in many ways on sperm metabolism, the current study was undertaken to modulat e the survival and fertilizing ability of bovine semen by incorporatio n of products from the oviduct or the follicle in extenders before fre ezing. Motility rates at 6 h in vitro showed a net positive effect whe n biological factors from total retentate or from a fraction of bovine follicular fluid (total retentate = 43%; fraction 2 = 54%), oviductal cell culture (total retentate = 43%; fraction 2 = 58%), or granulosa cell culture (total retentate = 43%; fraction 3 = 53%) were added to t he extenders compared with the addition of BSA (31%). Fraction 3 of gr anulosa cell culture retentate also had a significant stimulatory effe ct on the number of sperm that penetrated mucus of cows in estrous com pared with BSA (n = 205 vs. n = 159). The intracellular sperm Ca2+ con centrations were very different across treatments after thawing. Sperm from straws with BSA had the highest concentration. At 4 h, intracell ular Ca2+ concentration increased for all treatments, except that for sperm treated with BSA and Ca alone, internal Ca2+ declined. Heparin p lus Ca stimulated a greater internalization of Ca2+ than did Ca alone for retentate from bovine follicular fluid, oviductal cell culture, an d BSA treatments; glucose consistently and significantly reduced inter nalization. In vitro fertilization rates were similar, and no signific ant differences were observed across treatments. In summary, selected products from the female genital tract are capable of increasing survi val of bovine sperm, and some factors can affect the rapid sperm Ca2uptake without inhibiting in vitro fertilization potential.