Aa. Grippo et al., EFFECT OF BOVINE AMPULLARY AND ISTHMIC OVIDUCTAL FLUID ON MOTILITY, ACROSOME REACTION AND FERTILITY OF BULL SPERMATOZOA, Journal of Reproduction and Fertility, 105(1), 1995, pp. 57-64
Motility, acrosome reaction and oocyte fertilizing ability were assess
ed for bull spermatozoa after incubation in regional (isthmic or ampul
lary), bovine oviductal fluid, pooled by stage of the oestrous cycle.
Oviductal fluids collected daily from isthmic and ampullary cannulae i
mplanted in the same oviduct were divided into pools, representing two
oestrous cycle stages, based on daily serum progesterone concentratio
ns. Ejaculated bull spermatozoa were incubated for 0-6 h in each type
of oviductal fluid. Incubation in isthmic oviductal fluid collected du
ring the nonluteal stage, including oestrus and ovulation, decreased o
verall sperm motility (from 71.7% motile spermatozoa to 34.0%) and bot
h path (78 mu m s(-1) versus 86-89 mu m s-1) and progressive (74 mu m
s(-1) versus 83-85 mu m s(-1)) velocities of spermatozoa motion. Sperm
atozoa incubated in isthmic, non-luteal oviductal fluid had a higher r
ate and extent of sperm acrosome reaction (213% of control versus 136-
161% of control by 2 h incubation) compared with spermatozoa incubated
in other oviductal fluid types. However, incubation in nonluteal ampu
llary fluid increased the number of spermatozoa, which were both acros
ome reacted and live, and able to fertilize bovine ova (88.7% fertiliz
ed versus 75-81%). Glycosaminoglycan concentrations were similar among
types of oviductal fluid (0.77-0.88 mg ml(-1)). These findings indica
te that oviductal fluid differentially affects sperm function, dependi
ng on the oviduct region and the stage of the oestrous cycle at which
the fluid was obtained.