Björkman S, Oliviero C, Rajala-Schultz P J, Soede N M, Peltoniemi O A T
Production Animal Hospital, Department of Production Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Finland.
Production Animal Hospital, Department of Production Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Finland.
Theriogenology. 2017 Apr 1;92:36-44. doi: 10.1016/j.theriogenology.2017.01.003. Epub 2017 Jan 6.
The hypothesis was that a prolonged parturition impairs placenta expulsion and can lead to retained placentas in sows. Furthermore, we hypothesized that application of oxytocin around the time of expulsion of the first placental part improves placenta expulsion. We recorded 142 parturitions of 101 Yorkshire x Large White sows. We determined parity, gestation length, number of liveborn and stillborn piglets, farrowing duration (time between first and last piglet) and the outcome variables: number of expelled placental parts, placenta expulsion duration (time between first and last placental part), first placental part expulsion (time between last piglet and first placental part) and last placental part expulsion (time between last piglet and last placental part). The relationship between farrowing duration and each of the outcome variables was investigated using four distinct multivariable models. Use of oxytocin (used in 44 out of 142 parturitions) increased number of expelled placental parts (3.8 ± 0.2 vs. 2.9 ± 0.3; P = 0.035), decreased the placenta expulsion duration (172 ± 44 vs. 328 ± 26 min; P = 0.011) and time of last placental part expulsion (148 ± 48 vs. 300 ± 24 min; P = 0.025). If oxytocin was not used, farrowing duration obeyed a quadratic relationship with the number of expelled placental parts (P = 0.001), placenta expulsion duration (P = 0.002) and time of last placental part expulsion (P = 0.024). If oxytocin was used, number of expelled placental parts was positively associated with number of liveborn piglets (β = 0.2 ± 0.1; P = 0.002) and affected by parity. 5th parity sows expelled more placental parts (4.3 ± 0.4) than 4th (3.2 ± 0.3; P = 0.024) and 3rd parity sows (2.7 ± 0.4; P = 0.008). Furthermore, placenta expulsion duration was positively associated with number of liveborn piglets (β = 18 ± 8 min; P = 0.025). First placental part expulsion was negatively correlated with farrowing duration (β = 0.3 ± 0.1; P = 0.001). Sows that experienced total (no expulsion of placental parts; n = 4) and partial retained placentas (no expulsion of placental parts after birth of the last piglet; n = 4) had longer farrowing durations (1009 ± 275 and 734 ± 136 min) than sows with no retained placentas (369 ± 202 min; P = 0.021 and P = 0.004). The results show that a prolonged parturition impaired and oxytocin improved placenta expulsion in sows. Furthermore, retained placentas occurred in 3-6% of the sows and was correlated with a prolonged parturition.
我们的假设是，分娩时间延长会影响母猪胎盘的排出，导致胎盘滞留。此外，我们还假设在排出第一个胎盘部分前后使用催产素可促进胎盘排出。我们记录了101头约克夏×大白母猪的142次分娩情况。我们确定了胎次、妊娠期长度、活产和死产仔猪数量、产仔持续时间（第一头仔猪与最后一头仔猪出生的间隔时间）以及结果变量：排出的胎盘部分数量、胎盘排出持续时间（第一个胎盘部分与最后一个胎盘部分排出的间隔时间）、第一个胎盘部分排出时间（最后一头仔猪与第一个胎盘部分排出的间隔时间）和最后一个胎盘部分排出时间（最后一头仔猪与最后一个胎盘部分排出的间隔时间）。我们使用四个不同的多变量模型研究了产仔持续时间与每个结果变量之间的关系。使用催产素（142次分娩中有44次使用）可增加排出的胎盘部分数量（3.8±0.2对2.9±0.3；P = 0.035），缩短胎盘排出持续时间（172±44对328±26分钟；P = 0.011）以及最后一个胎盘部分排出时间（148±48对300±24分钟；P = 0.025）。如果未使用催产素，产仔持续时间与排出的胎盘部分数量（P = 0.001）、胎盘排出持续时间（P = 0.002）和最后一个胎盘部分排出时间（P = 0.024）呈二次关系。如果使用催产素，排出的胎盘部分数量与活产仔猪数量呈正相关（β = 0.2±0.1；P = 0.002），并受胎次影响。第5胎母猪排出的胎盘部分（4.3±0.4）比第4胎（3.2±0.3；P = 0.024）和第3胎母猪（2.7±0.4；P = 0.008）更多。此外，胎盘排出持续时间与活产仔猪数量呈正相关（β = 18±8分钟；P = 0.025）。第一个胎盘部分排出时间与产仔持续时间呈负相关（β = 0.3±0.1；P = 0.001）。经历完全胎盘滞留（未排出任何胎盘部分；n = 4）和部分胎盘滞留（最后一头仔猪出生后未排出任何胎盘部分；n = 4）的母猪产仔持续时间（1009±275和734±136分钟）比无胎盘滞留的母猪（369±202分钟）更长（P = 0.021和P = 0.004）。结果表明，分娩时间延长会损害母猪胎盘排出，而催产素可改善胎盘排出。此外，3 - 6%的母猪出现胎盘滞留，且与分娩时间延长相关。
