POIKILOTHERMIC TRAITS AND THERMOREGULATION IN THE AFROTROPICAL SOCIALSUBTERRANEAN MASHONA MOLE-RAT (CRYPTOMYS-HOTTENTOTUS-DARLINGI) (RODENTIA, BATHYERGIDAE)
Nc. Bennett et al., POIKILOTHERMIC TRAITS AND THERMOREGULATION IN THE AFROTROPICAL SOCIALSUBTERRANEAN MASHONA MOLE-RAT (CRYPTOMYS-HOTTENTOTUS-DARLINGI) (RODENTIA, BATHYERGIDAE), Journal of zoology, 231, 1993, pp. 179-186
When acclimated for two months at 26-degrees-C the social Mashona mole
-rat Crytomys hottentotus darlingi has a mean (+/-S.D.) resting metabo
lic rate (RMR) of 0.98+/-0.14 cm3 O2 g-1 h -1 (n=21), within a thermal
neutral zone (TNZ) of 28-31.5 C ambient temperature (Ta). The body te
mperature (Tb) of the mole-rat is very low, 33.3+/-0.5 C, and remained
stable between 25-31.5-degrees-C (n=28). Above 33-degrees-C, Tb incre
ased to a mean of 34.7+/-0.77 C(n=28) (Ta range 33-39-degrees-C). Belo
w Ta 25-degrees-C, Tb showed strong poikilothermic tendencies, with Tb
dropping to a mean of 26.8+/-1.16 C at 6-degrees-C, whereas above Ta
25-degrees-C, Tb varied in a typically endothermic pattern. The conduc
tance is high 0.19+/-0.03 cm3 O2 g-1 C-1 (n=28) at the lower limit of
thermoneutrality. The mean RMR at 18-degrees-C (the lowest Ta tested)
was 2.63+/-0.55 cm3 O2 g-1 h-1 (n=7) which is 2.6 times that of the re
sting metabolic rate in the TNZ.