ABSTRACT
Egg yolk immunoglobulin(IgY),also called egg yolk antibody,is a specific antibody secreted by birds after stimulation with certain antigens.For that it exhibits good resistance to heat,acid and proteinase-mediated degradation,its early-stage products were developed as food or food additives,and they have gained great social and economic benefits in both food safety and ecological agriculture fields.Due to the specific antibodies contained in these products,the products can help to resist pathogen infection.Therefore egg yolk antibody shows great value for development and application in the prevention and treat ment of animal and human diseases,and also shows great potential in human health care area.This review focuses on the development and applications of IgY biologics related with antiviral,antibacterial,antiparasitic and antitumor activities.