Submitted to: American Association of Avian Pathologists
Publication Type: Proceedings
Publication Acceptance Date: September 20, 1996
Publication Date: N/A
Interpretive Summary: Avian coccidiosis, a major parasitic disease of poultry, costs the poultry industry > $450 million in annual losses. Drug resistance is increasing and thus the development of an alternate control strategy is needed. ARS scientists investigated the host intestinal response to this parasite in order to develop a coccidial vaccine. In this report, the nature of the host-parasite interaction is detailed. Enhanced understanding of the host immune system will lead to the development of an immunological control strategy against coccidiosis.
The intestine constitutes a large proportion of the animal's immune system. Both resident and migratory lymphocytes located in the intraephithelium and lamina propria play an important role as the first line of defense on mucosal surfaces. Expression of mucosal immunity is mediated by various T lymphocyte subpopulations through production of soluble cytokines and lymphokines. Furthermore, various selectins and integrin adhesion molecules mediate lymphocyte migration to the gut. Advances in our understanding of the development and function of the intestinal immune system will soon enable the development of novel vaccination and immunization strategies for control of intestinal infections. The purpose of this review is to summarize our current understanding of the avian intestinal immune system and mucosal immune responses to enteric pathogens of economic importance in chickens such as Eimeria, cryptosporidia and salmonella.