Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 10, 2007
Publication Date: April 20, 2007
Citation: Lillehoj, H.S. 2007. Passive Protection Against Coccidiosis. Proceedings of Association of National Poultry Science. April 19-25. Acapulco, Mexica. P13.
Interpretive Summary: Coccidiosis is caused by several distinct species of intestinal parasites called Eimeria. Currently, drugs and live parasites are commonly used to control coccidiosis. Development of novel control method for coccidiosis is needed to reduce ecomonic losses due to coccidiosis. In this paper, ARS scientist developed a new method using immune egg antibody powder which was obtained from the hens hyperimmunized with a purified recombinant coccidia protein. Using this method, goold level of protection was obtained when newly hatched chickens were fed diets supplemented with hyperimmune egg antibody powder. This study has established a new avenue of controlling avian coccidiosis and will help poultry industry to design new therapeutics that will reduce economic loss due to avian coccidiosis.
The protective effect of chicken egg antibody (IgY) powder which were prepared from hens hyperimmunized with a purified recombinant protein from Eimeria acervulina merozoites (3-E) was evaluated in a chicken challenge model with 2 different Eimeria species, E. acervulina and E. tenella. The chickens were randomly divided into control and several treatment groups. The treatment groups were given standard diet which contains 0.1, 1, 5, 10 or 20 % of the IgY powder containing antibodies against 3-1E (3-1E/IgY). Control groups were comprised of chickens nontreated chickens or treated with IgY powder without 3-1E antibodies. The chickens were orally challenged with 103 E. tenella or 5 × 103 E. acervulina oocysts and fecal oocyst count and body weight gain were used to assess the effectiveness of 3-1E/IgY antibody treatment. In chickens which were fed with standard diet supplemented with 10% or more 3-1E/IgY-containing powder, average oocyst outputs which were significantly lower after challenge infection when compared to chickens which were nontreated or fed diet containing IgY without 3-1E antibodies. The best results were observed in the groups which received 10% or higher 3-1E/IgY powder in the feed resulting in significantly reduced oocyst production (P < 0.01 in the E. tenella-challenged group and P < 0.05 in the E. acervulina-challenged group). Significant improvement in body weight gain was also seen in these groups (P < 0.01 and P < 0.05, respectively). These results indicate that the 3-1E represents an important target antigen for coccidiosis prevention and the passive immunization of chickens with antigen-specific IgY powder is a promising method to confer protection against coccidiosis.