This work was designed to determine temperature conditions within the reproductive tract of the female pig and study their impact on ARTs. Temperatures were recorded using a laparo-endoscopic single-site surgery assisted approach and a miniaturized probe. Sows and gilts were used to address natural cycle and ovarian stimulation treatments, respectively. According to in vivo values, IVF was performed at three temperature conditions (37.0°C, 38.5°C and 39.5°C) and presumptive zygotes were cultured in these conditions for 20 h, while further embryo culture (EC) (21–168 h post-insemination) was maintained at 38.5°C. After 20 h, different fertility parameters were assessed. During EC, cleavage and blastocyst stages were evaluated. Sperm membrane fluidity at the experimental temperatures was studied by using differential scanning calorimetry and fluorescence recovery after photobleaching techniques. An increasing temperature gradient of 1.5°C was found between the oviduct and uterus of sows (P < 0.05) and when this gradient was transferred to pig in vitro culture, the number of poly-nuclear zygotes after IVF was reduced and the percentage of blastocysts was increased. Moreover, the temperature transition phase for the boar sperm membrane (37.0°C) coincided with the temperature registered in the sow oviduct, and sperm membranes were more fluid at 37.0°C compared with those of sperm incubated at higher temperatures (38.5°C and 39.5°C). These data suggest that there may be an impact of physiological temperature gradients on human embryo development.

中文翻译：

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模拟母猪输卵管和子宫之间的温度梯度可提高体外胚胎培养产量。

这项工作旨在确定雌性猪生殖道内的温度条件并研究它们对 ART 的影响。使用腹腔内窥镜单点手术辅助方法和微型探头记录温度。母猪和小母猪分别用于解决自然周期和卵巢刺激治疗。根据体内值，IVF 在三种温度条件下（37.0°C、38.5°C 和 39.5°C）进行，推定受精卵在这些条件下培养 20 小时，同时进一步胚胎培养 (EC)（受精后 21-168 小时）保持在 38.5°C。20 小时后，评估不同的生育参数。在 EC 期间，评估了卵裂和囊胚阶段。通过使用差示扫描量热法和光漂白技术后的荧光恢复来研究实验温度下的精子膜流动性。发现母猪输卵管和子宫之间的温度梯度增加了 1.5°C ( P  < 0.05) 并且当该梯度转移到体外猪时体外受精后多核受精卵数量减少，囊胚百分比增加。此外，公猪精子膜的温度转变阶段（37.0°C）与母猪输卵管中记录的温度一致，与在较高温度（38.5°C 和39.5°C）。这些数据表明生理温度梯度可能对人类胚胎发育有影响。