Used in immunological research to quantify secreted immunoglobulin A (sIgA) levels in biological samples from rats. This kit enables researchers to assess mucosal immune responses, particularly in studies related to gut health, respiratory infections, oral immunizations, and intestinal inflammation. It is commonly applied in preclinical studies involving rodent models to evaluate the impact of probiotics, pathogens, drugs, or dietary interventions on mucosal immunity. The assay provides a sensitive and specific measurement of sIgA in saliva, fecal extracts, intestinal lavage fluids, and other mucosal secretions.