Fetal and maternal body temperatures measured by radiotelemetry in near-term sheep during thermal stress

GOELST. Fetal and maternal body temperatures measured by ra-diotelemetry in near-term sheep during thermal stress. J. Appl. Physiol. 72(3): 894-900, 1992.-Using implanted radioteleme-ters, we have measured amniotic temperature and fetal lamb and pregnant ewe body temperatures continuously over the last 34 days of gestation and during conditions of thermal stress. Body temperature of the fetus was-0.6OC higher than that of the mother, and the fetomaternal temperature differ-ence remained constant over the last 25 days of gestation, until the immediate prepartum period, when it rose. During expo-sure to mild heat stress (35°C dry-bulb temperature, 24°C wet-bulb temperature), ewe and fetal body temperatures rose, but fetal temperature rose at a slower rate. Thus the fetomaternal temperature gradient fell significantly in the initial exposure period. In an environment of 4”C, body temperature of the preg