Thermoregulation And Standard Metabolism Of The Slender Mongoose (Herpestes Sanguineus)

Abstract

The aims of this study were to measure standard metabolism of the slender mongoose Herpestes sanguineus in order to (a) resolve discrepancy in literature concerning standard metabolism of small carnivores and (b) give more information on metabolism of carnivores which w i L'l allow us to evaluate whether or not differences exist between metabolism of herbivores and that of the carnivores as has already been shown between passerine and non-passerine birds. In controlled laboratory conditions, oxygen uptake, rectal temperatures, total and respiratory evaporative water loss and respiratory frequencies were measured at ambient temperatures of 5, 10, 20, 26, 31 and 43°C. Further measurements of• oxygen uptake, activity and abdominal temperatures were taken at; different ambient temperatures over 24 hour periods. Within the thermal neutral zone, resting post absorptive oxygen uptake was 0.76+0.15 ml02 (g h)-I,close to the value predicted for mammals of that size (o,bout 42 Kcals per day for a 500g mongoose). Rectal temperature was 38.7 +0. 030C while respiratory frequency remained at about 40 breaths per minute, between ambient temperature of 26 and 310C. In the hot environment, the animals regulated at progressively higher rectal temperatures Thermal equilibrium could not be attained at Ta of 430C and the rectal temperature continued-to rise. Heat loss at this temperature exceeded heat production by about 16%. Most of the heat was lost via cutaneous evaporation, respiratory evaporation accounting for about 26% of the total heat loss by evaporative means. In the cold environment (5°C) the metabolic rate was double that measured within thermal neutral zone. Shivering and curling up into a ball-like posture was observed at Ta of 5°C. Diurnal rhythms in activity, abdominal temperature and oxygen uptake were-e observed. The phase. Relationship may suggest causal connection between the three parameters.