A Simplified Method for the Culture of Blatella germanica under Aseptic Conditions

Abstract

IN developing the work recently begun in this laboratory¹ on the sterol metabolism of the German cockroach, Blatella germanica, it has become necessary to use aseptic techniques as an aid in defining the metabolic contribution of the normally occurring microbial inhabitants of the gut of the insect. The technique for the aseptic culture of this insect which has been described² entails the use of a watering device which is of undesirable complexity, while simpler devices³ which could be adapted for aseptic work involve the renewal of a sterile water-supply at intervals throughout the experiment. Since these feeding experiments frequently last for three months or longer the risk of contamination during opening the culture vessels, especially in a laboratory not fully equipped for aseptic work, becomes quite high. I have therefore devised a simple procedure which has made it possible to rear healthy colonies of German cockroaches aseptically in glass jars without the need of opening them for at least five months and which could well be used for maintaining colonies undisturbed for twice this length of time. The method also provides for the sterility testing of the young nymphs without the necessity of opening the hatching tubes for removal of inoculation samples.