Brain and deep abdominal temperatures during induced fever in pregnant rabbits

Rectal (Tre), hypothalamic (Thy), and uterine (Tut) temperatures were monitored before and during the course of prostaglandin E1 (PGE1)-induced fever in pregnant rabbits on days 10, 12, 16, 18, 24, 26, 29, and 31 after mating. Tre and Tut were consistently higher than Thy in both nonpregnant and pregnant normothermic does, but changes in the three parameters were closely correlated. In near-term rabbits, both Tre and Thy were significantly lower than in the same does before pregnancy, and the Tre-Thy difference was significantly less than for the same animals before pregnancy, with near-term Thy maintained at a relatively higher level than Tre or Tut. Fever height in the various stages of pregnancy was not different from that observed before mating.