Immunoglobulins
They are proteins produced by stimulated B-lymphocytes in response to an antigen stimulation, Therefore, they are antibodies that act as a specific defense of the organism.
Several types of immunoglobulins are distinguished: IgG, IgM, IgA, IgD and IgE. In swine, four types has been described: IgM, IgG, IgA and IgE.