Avian flu killed 52 million birds in 2022 in the United States, taking a toll on the poultry and egg industry and causing infections in humans. A method to monitor and diagnose avian flu in birds is necessary, and a potential way is through the analysis of IgY, the major class of antibody in birds. Because infections change the antibody repertoire, or set of antibodies produced in an individual, study of the antibody repertoire can reveal current and previous infections of a bird. Finding the amino acid sequence of antibodies can yield more specific data, such as binding capabilities and the genetic code of an antibody. Mass spectrometry is a procedure to measure the mass-to-charge ratio of particles, and it can identify molecules based on this characteristic. An antibody solution of IgY from egg yolks will be analyzed with a mass spectrometer, and the antibody repertoire and amino acid sequence will be collected. Both intensity and diversity of the antibodies will be measured; if the concentration of antibodies of a certain mass is high, it signifies a current infection, and if there are many antibodies of different masses, it signifies high diversity. The results may open a new method to study an animal’s present immunity that can be applied to combat spread of disease in avian species.