Patent ID: 8546149

Claim:
A method for determining an antigen content of a porcine circovirus type 2 (PCV-2) antigen in a mixture comprising the PCV-2 antigen and a composition comprising (i) a Mycoplasma hyopneumoniae antigen and (ii) antibodies that are-capable of binding with the PCV-2 antigen; wherein the antibodies and the PCV-2 antigen form antigen-antibody complexes that interfere with the antigenicity of the PCV-2 antigen; the method comprising the steps of: a) incubating the mixture for at least 8 hours with an acid solution to dissociate the antigen-antibody complexes, thereby recovering the antigenicity of the PCV-2 antigen; wherein the pH range of the acid solution is pH 1.0-3.0; and b) determining the antigen content of the PCV-2 antigen following step a) by means of an immunoassay.