Figure 2.
Percentage of observations in different temperatures within the thermal gradient based on the reproduction stage and during inactive behaviors. The effects of the reproductive stage (nonpregnant; mid-gestation: 58.5 ± 5.68 d; and late gestation: 104.7 ± 2.8 d) on thermal preference. Temperature within the thermal apparatus is plotted on the0 x-axis, and the percentage of time observed during inactive behaviors is plotted on the y-axis as a log10 + 0.001 scale. Cubic peaks are indicated by vertical lines corresponding to the reproductive stage. Standard error bars are located at the temperatures of the five thermal zones (10.4, 19.2, 23.6, 27.5, and 30.5 °C); different letters denote significant Tukey pairwise comparisons (P < 0.01), and no letters given where no significance was found between the three reproductive stages. The gray box indicates the recommended temperatures (10 to 25°C) for sows or boars > 100 kg (Federation for Animal Science Societies, 2020).