Application of egg yolk antibodies as replacement for antibiotics in poultry

Control of Salmonella in Poultry Through Vaccination and Prophylactic Antibody Treatment

“…These yolks, when chemically extracted, had a high crude extract mean anti-Typhimurium antibody titre (ELISA titre of 6900). The extract titres were higher than the initial serum level and similar observations have been made in numerous studies (Rose et al, 1974;Kariyawasam et al, 2004;Malik et al, 2006;Yegani and Korver, 2010).…”

“…The initial concentration of egg yolk containing IgY may be critical as these orallyadministered antibodies, like any other protein molecule, are susceptible to denaturation by the acidic pH of the proventriculus and gizzard and degradation by proteases (Yegani and Korver, 2010). However, there are reports in the literature that suggest that the IgY F ab fragments maintain their ability to bind antigen, even after exposure to pepsin and trypsin and at pH 4.0 (Shimizu et al, 1988;Carlander et al, 2000;.…”

“…These antibodies, post-digestion, would decline in immunological activity and concentration as they progressed from the proximal to distal regions of the intestine, due to viscosity and passage rate, but remain detectable in the caecum and therefore reducing the probability of antibody encountering and binding the antigen (Reilly et al, 1997;Wilkie et al, 2006;Yegani and Korver, 2010). These factors may influence the ability of IgY to prevent colonisation by specific pathogens in the lower parts of the intestinal tract.…”

The potential application of avian egg antibodies with emphasis on immunotherapeutic and immunodiagnostic purpose

“…The avian egg contains all the necessary nutrients and growth factors required for the developing embryo, including antibodies that are transported from the blood of the hen into the egg yolk to provide immunity to the chick (Yegani and Korver, 2010). The production of antibodies (Abs) in chickens and the extraction of specific Abs from egg yolk (IgY Abs) are increasingly attracting the interest of the scientific community as demonstrated by the significant growth of the IgY literature.…”

“…Passively administered antibodies have the ability to provide rapid and immediate protection; for example, against agents of bioterrorism (Casadevall et al, 2004). The reduction of antibiotics use in the livestock industry and increasing evidence that resistant organism may pass from animals to humans, resulting in infections that are harder to treat (Yegani and Korver, 2010). Therefore, this paper aim to assess several aspects of avian immunoglobulins and the avian immune system, including the structure, production and purification of IgY, and to outline many current and potential applications of IgY, especially in the areas of immunotherapy and immunodiagnostics.…”