Naked mole-rats exhibit pronounced thermolability, with body temperature closely tracking that of ambient. We questioned whether this pattern would be maintained with pregnancy. Body mass, body composition, rectal temperature and basking behaviour of breeding females and their mates were monitored in early (weeks 1-3), mid (weeks 4-7) and late (weeks 8-10) pregnancy. All these variables increased significantly in mid and late pregnancy compared to non pregnant and early pregnant values. Body mass increments (25.8 ± 2.74 %), coupled with increased percentage body fat (31.9 ± 2.05 %) may contribute to the elevated body temperature during pregnancy. The increased mass leads to a reduced surface area to volume ratio. This together with improved insulation provided by increased percentage body fat reduces rates of heat loss. Furthermore, behavioral thermoregulation (basking) is increased during the latter stages of pregnancy. This decreases the thermal gradient, contributing also to a decline in heat loss with extended periods of basking as well as passive heat gain. Basking coupled with increased endogenous heat production contribute to the increase in body temperature with pregnancy. The shift in selected body temperature is presumed to be optimal for foetal development. All these changes with pregnancy, suggest a shift in the thermoregulatory set point with pregnancy.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology