Automatic and continuous recording of vaginal temperature (TV) using wearable sensors causes minimal disruptions to animal behavior and can generate data that enable the evaluation of temporal body temperature variation under heat stress (HS) conditions. However, the genetic basis of TV in lactating sows from a longitudinal perspective is still unknown. The objectives of this study were to define statistical models and estimate genetic parameters for TV in lactating sows using random regression models, and identify genomic regions and candidate genes associated with HS indicators derived from automatically-recorded TV. Heritability estimates for TV ranged from 0.14 to 0.20 over time (throughout the day and measurement period) and from 0.09 to 0.18 along environmental gradients (EG, − 3.5 to 2.2, which correspond to dew point values from 14.87 to 28.19 ˚C). Repeatability estimates of TV over time and along EG ranged from 0.57 to 0.66 and from 0.54 to 0.77, respectively. TV measured from 12h00 to 16h00 had moderately high estimates of heritability (0.20) and repeatability (0.64), indicating that this period might be the most suitable for recording TV for genetic selection purposes. Significant genotype-by-environment interactions (GxE) were observed and the moderately high estimates of genetic correlations between pairs of extreme EG indicate potential re-ranking of selection candidates across EG. Two important genomic regions on chromosomes 10 (59.370–59.998 Mb) and16 (21.548–21.966 Mb) were identified. These regions harbor the genes CDC123, CAMK1d, SEC61A2, and NUDT5 that are associated with immunity, protein transport, and energy metabolism. Across the four time-periods, respectively 12, 13, 16, and 10 associated genomic regions across 14 chromosomes were identified for TV. For the three EG classes, respectively 18, 15, and 14 associated genomic windows were identified for TV, respectively. Each time-period and EG class had uniquely enriched genes with identified specific biological functions, including regulation of the nervous system, metabolism and hormone production. TV is a heritable trait with substantial additive genetic variation and represents a promising indicator trait to select pigs for improved heat tolerance. Moderate GxE for TV exist, indicating potential re-ranking of selection candidates across EG. TV is a highly polygenic trait regulated by a complex interplay of physiological, cellular and behavioral mechanisms.

中文翻译：

---

基于随机回归模型的热应激条件下泌乳母猪自动记录阴道温度的纵向基因组分析


使用可穿戴传感器自动连续记录阴道温度 (TV) 对动物行为的干扰最小，并且可以生成数据来评估热应激 (HS) 条件下的暂时体温变化。然而，从纵向角度来看，哺乳母猪电视的遗传基础仍然未知。本研究的目的是使用随机回归模型定义泌乳母猪 TV 的统计模型和遗传参数，并确定与来自自动记录 TV 的 HS 指标相关的基因组区域和候选基因。随着时间的推移（全天和测量期间），TV 的遗传力估计范围为 0.14 至 0.20，沿环境梯度的范围为 0.09 至 0.18（EG，- 3.5 至 2.2，对应于 14.87 至 28.19 ℃ 的露点值）。 TV 随时间和沿 EG 的重复性估计值分别为 0.57 至 0.66 和 0.54 至 0.77。从 12:00 到 16:00 测量的电视具有较高的遗传力估计值 (0.20) 和重复性 (0.64)，表明这一时期可能是最适合录制电视用于遗传选择目的的时间段。观察到显着的基因型与环境的相互作用（GxE），并且极端 EG 对之间遗传相关性的中等高估计表明整个 EG 中选择候选者的潜在重新排序。鉴定出 10 号染色体 (59.370–59.998 Mb) 和 16 号染色体 (21.548–21.966 Mb) 上的两个重要基因组区域。这些区域含有与免疫、蛋白质转运和能量代谢相关的基因 CDC123、CAMK1d、SEC61A2 和 NUDT5。 在四个时间段内，14 条染色体上分别有 12、13、16 和 10 个相关基因组区域被确定为 TV。对于三个 EG 类别，分别为 TV 确定了 18、15 和 14 个相关基因组窗口。每个时间段和 EG 类别都具有独特的丰富基因，具有确定的特定生物学功能，包括神经系统、新陈代谢和激素产生的调节。 TV 是一种具有显着附加遗传变异的遗传性状，代表了选择猪以提高耐热性的有希望的指示性状。 TV 存在中等 GxE，表明 EG 中的候选者可能会重新排名。 TV 是一种高度多基因性状，受生理、细胞和行为机制复杂的相互作用调节。