Oviductal isthmic motility patterns as monitored by Polyview~TM in unrestrained sows around ovulation

摘要

A method for monitoring oviductal isthmic motility in sows incorporating a computer programme (Polyview~TM) was developed. This method was found to be reliable and easy for recording and analysing data. Isthmic motility patterns were monitored from11 h prior to and up to 36 h after ovulation in 13 unrestrained multiparous sows during their second oestrus after weaning. The amplitudes and frequencies of phasic pressure fluctuations in relation to the hormonal profiles were also calculated. The isthmic motility patterns were regular before ovulation changing to wave patterns during the peri-ovulatory period and eventually to irregular patterns after ovulation. The amplitudes and frequencies of phasic pressure fluctuations in were significantly higher (p<0.05) prior to and soon after ovulation than afterwards. Plasma oestradiol-17#beta# levels significantly (P < 0.05) decreased before ovulation while plasma progesterone levels increased significantly (P < 0.05) after ovulation. Despite a significant decrease in the plasma levels of oestradiol-17#beta# prior to prior to ovulation, the amplitudes and frequencies of phasic pressure fluctuations remained high until shortly after ovulation. This could have been due to the endogenous levels of oestradiol-17#beta# bound to the nuclear oestradiol-17#beta# receptors that might still have been present in the isthmus. Conversely, the irregular isthmic motility patterns, the decline in the frequencies of phasic pressure fluctuations and amplitudes seen afterovulation may have been due to the rising plasma levels of progesterone. The amplitudes and frequencies of phasic pressure fluctuations were highest at the time when oestradiol-17#beta# levels were highest and when progesterone levels were low. It can be concluded that the changes in the isthmic motility patterns, amplitudes and frequencies of phasic pressure fluctuations in relation to the changes in the plasma levels of oestradiol-17#beta# and progesterone seen in the present study prior to and afterovulation indicate a possible role of the oviduct in regulating gamete transport.