A method for species-independent measurement of complement (C) activation in animals. The method comprises taking samples in the range of 3-100 microliter of anticoagulated blood, plasma or serum of an animal (specimen), mixing the specimen with a specificity converting protein matrix (SCM), mixing to the specimen/SCM mixture an activator of the C system (Act), incubating the specimen/SCM/Act mixture at a temperature between 36° C. to 38° C. for a time of 5-120 min and determining the production of one or more human proteins by ELISA or other analytical methods.