A quantitative study of the effect of endotoxin on embryonating chicken eggs.

A quantitative study of the effect of endotoxin on embryonating chicken eggs revealed the importance of several variables. In the study, the chorioallanotic membrane was detached (i.e.,dropped) from the eggshell membrane on the 9th and 11th incubation days. Various doses of endotoxin in various amounts of diluent were applied on the dropped membrane on the 11th day. Embryo deaths were greater when the membrane was dropped on the 11th day. Within the limits of our trial, the variables were, in decreasing order of significance: 1) the day the membrane was dropped; 2) the amount of endotoxin applied; and 3) an interaction between 1 and 2. The volume of diluent had no significant effect on mortality. The importance of these variables is discussed with reference to the design of additional experiments with endotoxin.