Elmetwally M, Rohn K, Meinecke-Tillmann S
Institute of Reproductive Biology, University of Veterinary Medicine Hannover, Hannover, Germany; Faculty of Veterinary Medicine, Department of Theriogenology, Mansoura University, Mansoura, Egypt.
Institute of Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Hannover, Germany.
Theriogenology. 2016 Apr 1;85(6):1070-9.e1. doi: 10.1016/j.theriogenology.2015.11.018. Epub 2015 Dec 2.
In contrast to cattle or horses, uterine blood flow in small ruminants has been investigated predominantly after surgical intervention and chronic instrumentation. The objective of the present study was to investigate the clinical applicability of noninvasive color Doppler sonography to characterize blood flow in the maternal uterine artery of sheep, n = 11 (18 pregnancies) and goats, n = 11 (20 pregnancies). The following parameters were measured transrectally or transabdominally: blood flow volume, time-averaged maximum velocity (TAMV), resistance index (RI), pulsatility index (PI), Time-averaged mean velocity, impedance of blood flow (AB or systolic/diastolic [S/D] velocity ratio), peak velocity of blood flow and blood flow acceleration. Examinations started 2 weeks after breeding and continued at 2-week intervals until parturition. Outcomes for sheep and goats were similar and will be discussed together. Based on noninvasive color Doppler sonography, blood flow volume increased (approximately 60-fold, P < 0.0001) until the end of pregnancy, with a rapid increase early in gestation, and a slow increase after week 18. Time-averaged maximum velocity in the uterine artery increased (approximately 4-fold; P < 0.0001) throughout pregnancy in sheep and goats. Furthermore, for uterine artery blood flow, there was an effect of stage of pregnancy on PI and RI (P < 0.001 and P < 0.0001, respectively), both indices decreased until the end of gestation. Time-averaged mean velocity decreased from week 18 to 20 in both species. The blood flow acceleration increased (P < 0.0001) until week 16 and week 14 in sheep and goats, respectively, and then decreased until parturition. Similar to PI and RI, vascular impedance of the uterine decreased (P < 0.0001) throughout pregnancy. This is apparently the first study using noninvasive color Doppler sonography of uterine blood flow throughout physiological pregnancy in small ruminants. Clearly, this technology facilitates repeated, noninvasive assessments, with great potential for future studies.
与牛或马不同，小型反刍动物的子宫血流主要是在手术干预和慢性仪器植入后进行研究的。本研究的目的是探讨无创彩色多普勒超声在表征绵羊（n = 11，18次妊娠）和山羊（n = 11，20次妊娠）母体子宫动脉血流方面的临床适用性。经直肠或经腹测量以下参数：血流量、时间平均最大速度（TAMV）、阻力指数（RI）、搏动指数（PI）、时间平均平均速度、血流阻抗（AB或收缩/舒张[S/D]速度比）、血流峰值速度和血流加速度。检查在配种后2周开始，并以2周为间隔持续进行直至分娩。绵羊和山羊的结果相似，将一起讨论。基于无创彩色多普勒超声，血流量在妊娠末期增加（约60倍，P < 0.0001），在妊娠早期迅速增加，在第18周后缓慢增加。绵羊和山羊子宫动脉的时间平均最大速度在整个妊娠期间增加（约4倍；P < 0.0001）。此外，对于子宫动脉血流，妊娠阶段对PI和RI有影响（分别为P < 0.001和P < 0.0001），这两个指数在妊娠末期之前均降低。两种动物的时间平均平均速度在第18周到第20周均下降。绵羊和山羊的血流加速度分别在第16周和第14周之前增加（P < 0.0001），然后在分娩前下降。与PI和RI相似，子宫的血管阻抗在整个妊娠期间降低（P < 0.0001）。这显然是第一项在小型反刍动物生理妊娠期间使用无创彩色多普勒超声研究子宫血流的研究。显然，这项技术有助于进行重复的无创评估，具有很大的未来研究潜力。
