Ewe breed differences in cervical anatomy and cervicovaginal mucus properties: An international study

In sheep, cervical artificial insemination (AI) involves depositing semen at the opening, as it is not possible to traverse cervix due its complex anatomy. However, internationally this method yields low pregnancy rates when frozen-thawed used. An exception in Norway, which vaginal deposition of a natural estrus around 70%. As and secretions are principal factors influencing sperm transport site fertilization aim study was characterise differences anatomy well cervicovaginal mucus properties six European ewe breeds across three countries known have following AI with semen. These were Suffolk Belclare Ireland, Fur Norwegian White Sheep (NWS) Norway Ile de France Romanov (n = 28–30 ewes/breed). Cervicovaginal collected follicular luteal phases both synchronized cycle assessed for weight, viscosity colour. The anatomical characteristics (length cervix, number rings appearance external os) post-mortem. There type by breed interaction represented no production between cycle. there (P < 0.05). had lowest phase while NWS amount Overall, all breeds, higher than Despite reports having most divergent semen, overall types > length os affected ewes longer cervices but lower (both rates). conclusion, breed, these changes consistent their