【Detection purpose】 Feline calicivirus (FCV) infection is a feline viral respiratory diseases. The general clinical manifestations are mainly upper respiratory symptoms, namely depression, serous and mucous rhinorrhea, conjunctivitis, stomatitis, tracheitis, bronchitis, and biphasic fever. Feline calicivirus infection is a frequently-occurring disease in cats, with high morbidity and low mortality. Detecting cat vivo FCV is an Ig G antibody content are reactive immune case conditions. Clinical significance: 1) For the evaluation of the body before immunization; 2) Detection of the body's antibody titer after immunization; 3) Early detection and diagnosis during the period of feline Calicivirus virus infection.