Quantitative evaluation of the vasculature supplying the oviduct in pre-pubertal and sexually mature sows.

The present work was aimed at characterizing the regional vascularization of the oviduct in the pig to ascertain whether the number of terminal mesosalpingeal arterioles supplying the isthmus and ampulla is influenced by reproductive maturity and state of the estrous cycle. The total number of terminal arterioles (NTA) in the mesosalpinx was quantified under a stereomicroscope in latex injected ex-vivo reproductive tracts from pre-pubertal (n = 10) and mature sows (n = 34), the latter allocated into three phases of the estrous cycle: follicular (n = 12); early luteal (n = 11); and late luteal (n = 11). The NTA and density of terminal arterioles (DTA) changed little between pre-pubertal and mature sows or among sows of different reproductive status (P > 0.05). Conversely, both in pre-pubertal and mature sows the isthmus showed higher DTA (P < 0.001) than the ampulla. It is concluded that the pattern of vascularization supplying the porcine oviduct is essentially established before the onset of puberty so that neither cyclical changes coupled with the estrous cycle nor regional variations between the isthmus and ampulla are likely at the level of the terminal arterioles supplying the oviduct during the reproductive life.