Temperature and circadian effects on metabolic rate of South American echimyid rodents, Trinomys setosus and Clyomys bishopi (Rodentia: Echimyidae)

By

Fabio-Braga, Ana Paula
Klein, Wilfried

Type

Article

Date of Publication

2018-3-9

Original Publication

MycoKeys

Volume

35

Pages

1--6

Subjects

basal metabolic rate , fossoriality , Neotropical , Oxygen consumption , thermoneutral zone

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers 2011-

Identifiers

DOI: https://doi.org/10.3897/zoologia.35.e24572

 

Abstract

Basal metabolic rate (BMR) represents the lowest level of metabolic activity capable to sustain homeostasis in an endotherm and is an important tool to compare metabolic rates of different species. Echimyidae is the most specious family within caviomorph rodents, however, little is known about the biology of its species, such as Trinomys setosus (Desmarest, 1817) and Clyomys bishopi (Ávila-Pires & Wutke, 1981), a ground and an underground dwelling echimyid, respectively. The ambient temperature and circadian effects on metabolic rate were evaluated through closed-system respirometry for these two species, as well as the circadian effects on CO2 production and respiratory exchange ratio (RER). Trinomys setosus and C. bishopi showed the lowest metabolic rates (0.56 ± 0.02 mLO2.h-1.g-1 and 0.53 ± 0.03 mLO2.h-1.g-1, respectively) at 32 °C and during the light phase. Under laboratory conditions, T. setosus showed metabolic rate variation compatible with nocturnal activity, whereas C. bishopi activity cycle remains unclear. Both species showed BMR lower than expected by allometric regressions for rodents.