Domino Malgorzata, Domino Krzysztof, Pawlinski Bartosz, Sady Maria, Gajewska Magdalena, Gajewski Zdzislaw
Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences - Szkola Glowna Gospodarstwa Wiejskiego, Nowoursynowska 100, 02-797, Warsaw, Poland.
Veterinary Research Centre and Center for Biomedical Research, Faculty of Veterinary Medicine, WULS - SGGW, Nowoursynowska 100, 02-797, Warsaw, Poland.
Exp Physiol. 2019 Mar;104(3):322-333. doi: 10.1113/EP087451. Epub 2019 Feb 10.
What is the central question of this study? Does oestrous cycle synchronization influence myoelectrical activity of porcine myometrium? What is the main finding and its importance? Exogenous hormones used to synchronize oestrus in pigs altered myoelectrical activity, which was effectively modelled. Higher-order multivariate statistic modelling provided evidence of similar activity in both types of oestrus, but a larger order of EMG signals during induced oestrus. Higher-order statistical analysis of the probabilistic model suggests the beginning of the early follicular phase and the mid-luteal phase to be most important in evaluation of the natural patterns of myoelectrical activity. Higher-order multivariate cumulants are more informative than classical statistics in characterization of myoelectrical activity changes in porcine myometrium.
In pig production units, control of the oestrous cycle and synchronization of ovulation have become routine herd management procedures. During the oestrous cycle, in both induced and spontaneous conditions, the ovaries and the uterus undergo hormone-dominated physiological changes, which are consistent with the hypothesis that there is a functional role of uterine contractions in promoting fertilization. We have used electromyography to determine whether the use of exogenous hormones, such as equine chorionic gonadotrophin and human chorionic gonadotrophin, which have the potential to control the timing of ovulation in female pigs, changes the multivariate relationships between parameters of electrical bursts and modulates the patterns of myoelectrical activity. We used the mathematical approach of higher-order multivariate cumulants in complex modelling of the myometrial electrical activity. The experiment was conducted on 12 mature Polish Landrace sows, and uterine activity was recorded during both spontaneous and induced oestrous cycles. The burst parameters were determined using six features in the time domain and, after Fast Fourier transformation, in the frequency domain. Evaluation of myoelectrical activity patterns was conducted based on classical univariate statistical methods and multivariate probabilistic modelling. The classical statistical approach indicated weaker myoelectrical activity after hormonal stimulation, whereas the higher-order multivariate statistical model showed evidence of similar status of activity and a larger order of signals during induced oestrus. Routine oestrous cycle synchronization affects the multivariate probabilistic model of myometrial electrical activity.
本研究的核心问题是什么？发情周期同步是否会影响猪子宫肌层的肌电活动？主要发现及其重要性是什么？用于使猪发情同步的外源激素改变了肌电活动，且该活动得到了有效建模。高阶多元统计建模提供了两种发情类型中存在相似活动的证据，但诱导发情期间肌电信号的阶数更大。概率模型的高阶统计分析表明，卵泡早期和黄体中期的开始阶段在评估肌电活动的自然模式中最为重要。在表征猪子宫肌层肌电活动变化方面，高阶多元累积量比经典统计更具信息量。
在养猪生产单位中，发情周期的控制和排卵同步已成为常规的畜群管理程序。在发情周期中，无论是诱导发情还是自然发情状态下，卵巢和子宫都会经历以激素为主导的生理变化，这与子宫收缩在促进受精中具有功能性作用的假设相一致。我们使用肌电图来确定使用外源激素（如马绒毛膜促性腺激素和人绒毛膜促性腺激素），这些激素有可能控制母猪排卵时间，是否会改变电脉冲参数之间的多元关系并调节肌电活动模式。我们在子宫肌层电活动的复杂建模中使用了高阶多元累积量的数学方法。实验在12头成熟的波兰大白母猪上进行，在自然发情周期和诱导发情周期期间记录子宫活动。使用时域中的六个特征并在快速傅里叶变换后在频域中确定脉冲参数。基于经典单变量统计方法和多元概率建模对肌电活动模式进行评估。经典统计方法表明激素刺激后肌电活动较弱，而高阶多元统计模型显示诱导发情期间活动状态相似且信号阶数更大。常规的发情周期同步会影响子宫肌层电活动的多元概率模型。
