Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 20, 2005
Publication Date: April 1, 2005
Citation: Lillehoj, H.S., Dalloul, R., Min, W. 2005. Cyrokines and immunity to eimeria. recent progress on the cytokine regulation of intestinal immune responses to eimeria. Poultry Science 83:611-623.
Interpretive Summary: The major parasitic disease of poultry, coccidiosis, causes more than $800 million in losses in prophylactic medication and this number is expected to rise due to the increasing regulatory restrictions on the use of traditionally used drugs for coccidiosis control. Economic losses due to coccidiosis include mortality, malabsorption, inefficient feed utilization and impaired growth rate in broilers, and a temporary reduction of egg production in layers. Coccidia parasites are ubiquitously distributed worldwide. Developing novel immunological, genetic and/or molecular strategies are needed not only for identification of the Eimeria immunogens, but also for the general understanding of the basic immunobiology of host protective immunity to intracellular pathogens in the intestine. In this paper ARS scientists discuss new findings concerning chicken immune system and the novel methods to enhance natural immunity of poultry. Understanding the interplay between the host and the parasites in the intestine will help poultry industry for designing new control approaches against coccidiosis.
A variety of methods are available to combat avian diseases in the commercial setting, including improved farm management practices, use of antibiotic drugs, selection of disease resistant chicken strains, and manipulation of the chicken immune system. With increasing demands for developing alternative control programs for many poultry diseases, it is becoming important to understand the basic immunobiology of host-pathogen interactions in order to develop novel vaccination strategies. From studies carried out in many mammalian species, it is evident that host immune responses to intracellular pathogens are complex and involve many components of the host immune system. For enteric pathogens such as Eimeria and Salmonella, understanding cell-mediated immunity is most important since antibodies, although abundantly produced locally, can not access and act on these intracellular pathogens. In poultry, slow but increasing understanding of various components of host immune system mediating cellular immunity, is opening new opportunities for thorough investigation of the role of thymus-derived lymphocyte subpopulations and cytokines in normal and disease states. This paper will review recent progress with chicken cytokines that have been characterized, and discuss various experimental strategies to enhance host immunity to pathogens using chicken cytokines.