Metabolism during starvation/dehydration stress in two species of galagos

Abstract

ABSTRACT. Two species of galagos (G. senegalensis moholi and G. garnettii) were subjected to dehydration and starvation stress in order to determine whether, as is common in other animals, these hypometabolic prosimians would lower their metabolic rate even further. Dehydration was confirmed by losses in body mass, a decrease in fecal water content and a rise in urine osmolality. At the height of dehydration, 20 to 25 ~ reduction in body mass, 30 to 40 ~ reduction in fecal water content and urine osmolality ranging from 1.8 to 3.50smol kg -1 HzO, were recorded in some of the animals. Basal metabolic rate of 0.536 ml O~ (g'h) -1 in G. s. moholi and 0.302 ml O~ (g'h) -t in G. garnettii were recorded, representing 50 to 42 ~ reduction in metabolic rate, respectively, compared with mass specific values. In none of the tested animals did we observe significant reduction in basal metabolism during dehydration/starvation stress compared with the rates observed during the control period. Basal metabolism in the bushbabies seems to have reached the lowest level and no further adjustment is apparently possible as a strategy for energy saving during starvation and/or dehydration stress.

Lack of Torpor in Free-Ranging Southern Lesser Galagos, Galago moholi: Ecological and Physiological Considerations

“…However, they adhered strictly to normothermy throughout the study period. Although it might be argued that a lack of torpor during our study period does not necessarily imply that G. moholi are physiologically incapable of it, Kamau and Müller [1989] showed that food deprivation and dehydration did not elicit a metabolic depression response in G. moholi. They concluded that basal metabolism in lesser bushbabies had reached the lowest levels and no further adjustments could be made in response to energy stress.…”

Basal Metabolic Rate, Body Weight and Diet in Primates: An Evaluation of the Evidence

“…The slow loris, Nycticebus coucang, is classified as an insectivore, although it eats only about 30% invertebrates with over 50% of its diet being plant food (10% gum and 50% fruit) [21]. The species classified as a plant-eating bushbaby (Galago crassicaudatus) by McNab and Wright (following the primary reference [14]) is most probably G. garnetti (as suggested by a second reference to the same study by one of the original workers [22]). As G. garnetti eats about 50% animal food, this species can not be classified as a plant-eating one (and, in fact, there is also evidence that G. crassicauda tus may also eat a high proportion of insects in some areas [21]).…”