Correlation of noninvasive surface temperature measurement with rectal temperature in swine

Skin and rectal temperature measurements were taken on 15 crossbred sows and gilts (225 kg) during the last 5 days of prepartum period and compared with those recorded in the first 8 days after parturition. The correlation of skin and rectal temperature values was not good during either period, although an increased correlation was noted in the postparturient period. The rectal temperature significantly (P less than 0.05) increased in the postparturient period, but the mean surface temperature was unchanged. This would indicate a decreased blood flow to the surface, since an equivalent blood flow to the surface after a rectal temperature increase would result in a concomitant mean surface temperature increase. The decreased flow to the surface of the animal was selective, since a significant (P less than 0.05) decrease in surface temperature was noted at the tailhead, perineum, vulva, mammae-caudal, and eye, whereas the surface temperature of the mammae-cranial and mammae-middle was significantly (P less than 0.05) increased.