[Passive immunization in dogs and cats]

Antibodies play an important role in the defense against infectious diseases. Passive immunization provides immediate protection through transfer of exogenous antibodies to a recipient. It is mainly used for prophylaxis in dogs and cats that failed to receive maternal antibodies through the colostrum or when there is an acute risk to acquire infectious diseases. Only a small number of placebo-controlled studies have been published regarding the therapeutic use of passive immunization in small animals. While positive effects were reported in cats with acute virus infections of the upper respiratory tract and in dogs with distemper, no statistically significant influence could be demonstrated in the treatment of canine parvovirosis. Prospective, double-blinded, and placebo-controlled studies using adequate numbers of patients are warranted for a definitive statement regarding the therapeutic and prophylactic use of passive immunization in dogs and cats.