Body mass, body temperature (T(b)), and oxygen consumption were measur
ed in male and female large-eared tenrecs (Geogale aurita) during the
breeding season. Body temperature paralleled ambient temperature (T(a)
) in all individuals, though T(b) was more elevated above T(a) in preg
nancy and lactation, especially if these events occurred concurrently.
Resting metabolic rate (RMR) in nonreproducing adults at 30-degrees-C
was 7.73 mL O2.h-1 (53% of the value expected from body mass). It did
not significantly increase with body mass, except in some pregnant in
dividuals (or those concurrently pregnant and lactating). Resting meta
bolic rate increased during reproduction and reached peak levels durin
g gestation. The energy cost of gestation with simultaneous lactation
was not additive and represents an energy saving. Resting metabolic ra
te in pregnancy and lactation was not influenced by litter size, and t
his implies there is no fixed minimum energy requirement for reproduct
ion in this species. Mean daily energy expenditure of nonreproducing G
. aurita was 9.67 kJ.d-1 (2.6 X RMR). Daily energy expenditure during
gestation attained higher levels than those attained in nonreproducing
individuals and gradually decreased during lactation. It is proposed
that an increased level of RMR may be essential for reproduction in G.
aurita. However, the cost of reproduction is often reduced by concept
ion at postpartum estrus and concurrent pregnancy and lactation.