An invitro method for measuring myelopoietic activity in an animal by measuring the absolute neutrophil count present in a sample of diluted whole blood of the animal, the method comprising:
- contacting the sample of diluted whole blood with a substance that activates NADPH oxidase activity of the neutrophils present in the sample of diluted whole blood, and a chemiluminigenic substrate susceptible to reductive dioxygenation by the activated NADPH oxidase to yield chemiluminescence, wherein the chemiluminigenic substrate is lucigenin (N,N′-dimethyl-9,9′-biacridinium dinitrate);
- and
- quantifying the resulting reductive dioxygenation of the chemiluminigenic substrate lucigenin by measuring the emitted chemiluminescence from the dioxygenated chemiluminigenic substrate lucigenin using a portable or hand-held instrument capable of measuring light, wherein the amount of chemiluminescence correlates with the number of the neutrophils present in the sample, wherein the number of neutrophils present in the sample is indicative of myelopoietic activity in the animal.