Blood plasma glucose regulation in Wahlberg’s epauletted fruit bat

Abstract

Frugivores feed on fruits and nectars that contain different types of sugars in  different proportions, which provide these animals with energy. Wahlberg’s epauletted fruit bat (Epomophorus wahlbergi) has a high glucose intake irrespective of sugar concentration of nectar. It is not known how these bats regulate their blood plasma glucose concentrations in order to avoid the negative effects associated  with hyperglycemia. Fruit bats have a high amount of sugar intake in a short period of time which could cause a glucose challenge and it is therefore necessary to  determine whether these bats are able to regulate their blood plasma glucose concentrations within normal concentrations. This study investigated the diel  variations in blood plasma glucose concentrations of E. wahlbergi. Epomophorus wahlbergi‘s blood plasma glucose concentration was lower (5.24 ± 0.38 mmol/l) at 18:00 before feeding and increased during/after feeding (8.19 ± 1.24 mmol/l) but  bats appeared to regulate it within limits. Their range in concentrations was higher than the normal mammalian blood plasma glucose concentrations range.  Consequently these bats appear to regulate their blood plasma glucose   concentration, although at a range higher than normal mammalian levels, and thus reduce the negative consequences associated with hyperglycemia.

Key words: frugivore, plasma glucose, glucose regulation, nectar, fruit.