Egg Yolk Antibodies: Production and applications in the diagnosis and treatment of animal diseases - A review

Abstract

Antibodies are extensively used in molecular biology, protein detection, cell isolation, immunopathology as well as in the diagnosis and treatment of various diseases in humans and animals. Rabbit and mice are the common mammalian species used for the production of both polyclonal and monoclonal antibodies. However, there are many advantages of raising antibodies in poultry. Chicken are phylogenetically distant from mammals and reacts strongly against highly conserved mammalian antigens. Also, chicken has a natural tendency to concentrate immunoglobulins in higher concentrations in egg yolk which makes subsequent collection and separation of antibodies easier by non-invasive methods than the separation from serum as in rabbits or mice. Moreover, by laying eggs each day a hen can act as a small antibody production unit. Eggs or egg yolk can be included as dietary components and egg yolk antibodies (EYA) have minimal toxic or side effects. At the same time, chicken immunoglobulin (IgY) can resist almost all gastric barriers in food animals, help in reducing gastrointestinal pathogen attachment and colonization, and improve digestion, thus can act as an excellent feed additive. The EYA can also be produced against various bacterial, fungal, or other immunogenic toxins and snake venoms. This review presents an overview of the production and purification techniques of EYA, its challenges and the applications in the diagnosis and treatment of animal diseases along with the conjectures on the future of IgY technology.