Thermoregulation and evaporative water loss in growing African giant rats Cricetomys gambianus

Abstract

Kalahari Gemsbok National Park, Private Bag X5890, Upington, 8800 Republic of South AfricaWith an increase in mass, weaned giant rat pups Cricetomys gambianus, showed a corresponding decline in mass specific metabolism, conductance and evaporative water loss. The decline in metabolism correlates better with mass than age, while conductance correlates better with age than mass. After 77 days of age the relative importance of dry thermal conductance increased and this is attributed to the testes becoming scrotal, and acting as a thermal window. The final desertion of the nest by young is suggested to coincide with the advent of an efficient thermoregulatory capacity.