Dietetic requirements and intermediary protein metabolism of an insect (Calliphora erythrocephala Meig.)

Summary Calliphora erythrocephala commonly known as the Bluebottle belongs to the Diptera. The larvae of this insect feed on food which is heavily infected with bacteria. Unlike most other terrestrial insects which excrete uric acid, the larvae of C. erythrocephala excrete ammonia, the most toxic end product of nitrogen metabolism. In this direct excretion of ammonia the larvae therefore behave like many aquatic animals. Under natural conditions the larvae grow very rapidly After a growth period of six or seven days they become mature, stop feeding, migrate to a dry place and then pupate.Although the larvae of C. erythrocephala usually live in an environment heavily contaminated with bacteria, it is possible to rear the larvae from the egg under aseptic conditions. When reared on adequate diets the aseptic larvae grow as well as those under natural conditions and metamorphose into normal adult flies.As in its mode of feeding and living the larvae of the Bluebottle are extreme specialists, it was to be expected that these specialisations may influence its dietetic requirements and intermediary metabolism. In how far these expectations came true was studied in a series of experiments in which the larvae were reared under aseptic conditions so that the intestinal bacteria could not interfere with the results of the feeding experiments and those of the study of the intermediary metabolism.