Effect of dietary sugars on tissue lipid and carbohydrate in developing honeybee larvae

Abstract

Changing the sugar concentration in the diet of laboratory-reared honeybee larvae to simulate that of the natural diet for worker larvae induced sugar patterns similar to those found in natural worker larval haemolymph but not in the fat body. Feeding a low-sugar-level diet to larvae in the incubator showed changes in haemolymph sugar concentration similar to those found in natural worker larvae. This indicates that the changes in sugar concentrations around the third and the fourth molts are not the consequence of the changes of the dietary-sugar level but are regulated by an endogenous system. Addition of sugar to the early larval diet in the incubator showed changes in sugar concentration resembling those found in natural queen larvae. This indicates that the high level of sugar in the early diet is a factor inducing the development of the endogenous system in queen larvae. High sugar level in the early diet decreased tissue carbohydrate concentration but increased tissue lipid concentration which may be essential for the maturation of the reproductive system in queen larvae.