The SNAP* test for IgG antibody levels in foals is an enzyme immunoassay for the semi-quantitative detection of immunoglobulin G (IgG) in horse serum, plasma, or whole blood. Diluted whole blood, serum, or plasma and the complex reaction materials are added to the SNAP* device. The device is then activated, releasing the chemicals stored inside the device. The color development on the sample spot in the device corresponds to the concentration of IgG in the test sample. Calibration spots on the device develop a color corresponding to IgG levels in the sample of 400 mg/dL and 800 mg/dL. Comparing the intensity of color development on the sample spot and the calibration spots allows for the assessment of IgG levels in the test sample. Color development on the calibration spots indicates that the test materials are active.