Nutrient composition of Romanomermis culicivorax in relation to egg production and metabolism

The nutrient composition of postparasitic females (newly emerged juveniles, newly moulted adults, and spent adults) and eggs of Romanomermis culicivorax was studied. Postparasites were obtained from experimentally infected larvae of the mosquito Aedes aegypti. Throughout postparasitic development, proteins increased and lipids decreased progressively as a proportion of the dry weight; the proportion of glycogen within the nematodes remained stable. The greatest decrease in the lipid moiety occurred during egg production. Eggs contained relatively low levels of lipids (12% dry weight) and approximately 20% of the dry weight of the eggs was unaccounted for by lipid, protein, and glycogen determinations. Chitin, mucoproteins and peptides were present in the eggs. The fatty acid composition of nematodes remained constant during postparasitic development; eggs contained a similar profile of fatty acids as postparasites, with marginally higher content of unsaturated fatty acids. Radiotracer studies showed that the eggs could oxidize glucose and palmitic acid..