Technical Report: Serial collections of placentomes during parturition in cattle and subsequent reproductive performance

Placental separation is a complex physiological event in reproductive physiology and the underlying molecular mechanisms remain unclear. When comparing different experiments the timing of tissue collections is a signifi cant consideration due to the variability in time between fetal expulsion and expulsion of the placenta (30 min to \u3e24 h). This makes comparison of tissues samples across animals diffi cult and supports the need for serial tissue collections within animal. Additionally, the instrument most commonly used, a modifi ed Richter-Resinsinger effeminator, for placentome collections is diffi cult to obtain and there are no data in the literature record regarding subsequent reproductive performance of animals subjected placentome collections. To facilitate continued research into the physiology behind placental separation, we designed an instrument from readily available components and performed serial transvaginal placentome collections in cattle. Three placentomes at 2-h intervals were collected after expulsion of the calf in 18 multiparous cows. There was no incidence of mortality and all cows resumed estrous after the procedure. Neither time from placentome collection nor age had a signifi - cant effect on pregnancy status at diagnosis (P \u3e 0.05). These results demonstrate the viability of and utility of this device for collecting multiple placentomes in cattle