Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/25/2010
Publication Date: 4/5/2011
Citation: Lee, S.H., Lillehoj, H.S., Park, D.W., Jang, S.I., Morales, A., Garcia, D., Lucio, E., Larios, R., Victoria, G., Marrufo, D. 2010. Induction of passive immunity in broiler chickens against Eimeria acervulina by hyperimmune egg yolk IgY. Poultry Science. 88(3):562-566. Interpretive Summary: This report describes a new method to control avian coccidiosis. Avian coccidiosis is caused by several distinct species of Eimeria parasites and cost poultry industry more than $ 3.2 million annual economic loss. Although drugs have been used successfully to control coccidiosis, increasing incidence of drug-resistant field strains of Eimeria compels the new strategy to control this infection. In this paper, ARS scientists and scientists at the Investigación Aplicada, S. A. de C. V. (IASA) in Puebla, Mexico work together to develop a commercially applicable new strategy using egg yolk-derived IgY antibodies to feed young birds to prevent avian coccidiosis. The results indicate a very successful strategy that can be fed to young birds with significant reduction of intestinal damage and improved body weight gains in treated birds. Furthermore, orally-administered Eimeria-specific IgY antibodies protective against more than one species of Eimeria. This is the first study that describes the development of commercially available hyperimmune antibodies which provide significant protection against avian coccidiosis in newly hatched chicks.
Technical Abstract: The protective effect of hyperimmune IgY fraction of egg yolk (SC) prepared from hens hyperimmunized with multiple species of Eimeria oocysts, on experimental coccidiosis was evaluated in young broilers. Chickens were continuously fed from hatch with a standard diet containing SC or a non-supplemented control diet, orally challenged at day 7 post-hatch with 5.0 × 103 live E. acervulina oocysts. Body weight gain between days 0 and 10 and fecal oocyst shedding between days 5 and 10 post-infection were determined as parameters of protective immunity. Chickens given 10% or 20% SC showed significantly increased body weight gain and reduced fecal oocyst shedding compared with control birds fed the non-supplemented diet. To test the effect of SC under lower supplementary dose with higher coccidia challenge dose, chickens were fed diets containing 0.01%, 0.02%, and 0.05% SC and challenged with orally 1.0 × 104 oocystsof E. acervulina. Total oocyst shedding was significantly (P < 0.05) reduced in chickens fed the 0.02% and 0.05% SC diets compared with animals fed the non-supplemented diet. Similarly, chickens fed 0.5% of SC diet and challenged with 1.0 × 104 oocysts exhibited reduced oocyst shedding compared with the control birds given 0.5% of IgY from non-immunized hen eggs, although body weight gain was not affected. We conclude that passive immunization of chickens with anti-coccidia IgY antibodies may provide protective immunity against coccidiosis challenge infection by reducing fecal oocysts shedding.