Thermal control of maternal contact bouts: the interbout interval.

Cooling mother rats by means of sodium salicylate injections did not curtail the intervals between maternal contact bouts. To the contrary, the interbout intervals were prolonged, suggesting that the relief from hyperthermia is a necessary but not a sufficient condition for the reinitiation of pup contact by mother rats. The ability of sodium salicylate to suppress maternal temperature suggests that pyrogenic and lactational increases in temperature may have some common feature.