REPRODUCTIVE ENERGETICS OF THE TENRECIDAE (MAMMALIA, INSECTIVORA) .1.THE LARGE-EARED TENREC, GEOGALE-AURITA

Citation
Pj. Stephenson et Pa. Racey, REPRODUCTIVE ENERGETICS OF THE TENRECIDAE (MAMMALIA, INSECTIVORA) .1.THE LARGE-EARED TENREC, GEOGALE-AURITA, Physiological zoology, 66(5), 1993, pp. 643-663
Citations number
77
Categorie Soggetti
Zoology,Physiology
Journal title
ISSN journal
0031935X
Volume
66
Issue
5
Year of publication
1993
Pages
643 - 663
Database
ISI
SICI code
0031-935X(1993)66:5<643:REOTT(>2.0.ZU;2-C
Abstract
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.