| Abstract: | To assess the role of ambient temperature on the expression of adultlike control over suckling behavior of infant rats, preweanling pups were tested for nipple attachment and milk intake while suckling in either room temperature (25°C) or nest temperature (34°C). In one experiment, attachment latency was measured following 0, 4, or 24 hr of deprivation at 3, 6, 9, 12, or 15 days of age. Latency was generally reduced by testing in high ambient temperature. Increasing deprivation reduced latency at all ages. Elevated temperature, however, did not accentuate deprivation-dependent differences. In a 2nd experiment, milk intake via a posterior tongue cannula was measured in pups 5, 10, 15, or 20 days of age, suckling at either room or nest temperature. Environmental temperature did not significantly affect intake at any age. These data eliminate ambient temperature as a critical factor for adultlike control of suckling behavior in infant rats. |
