Submitted to: International Journal of Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2010
Publication Date: 6/10/2010
Citation: Lee, K., Lillehoj, H.S., Siragusa, G. 2010. Direct-Fed Microbials and Their Impact on the Intestinal Microflora and Immune System of Chickens. International Journal of Poultry Science. 47:106-114. Interpretive Summary: Development of safe and effective alternative methods is becoming a priority for poultry industry due to increasing concerns about increasing drug-resistance of poultry pathogens. A close relationship exists between the development of the normal intestinal microbial population and resistance against enteric pathogens, and it is now well-known that the gut microflora plays a critical role in maintaining homeostasis which is critical for maintaining optimal animal health. Direct-fed Microbials (DFMs) have received renewed attention in recent years as prophylactic agents against intestinal diseases by balancing the normal microfloral population and by modulatioin of host immunity. The work described in this paper illustrates various ways DFM can be used to enhance host innate immunity to reduce economic losses due to enteric diseases in poultry. Recent developments in poultry genomics and immunology will facilitate the development of antibiotic-free alternative disease control strategy against mucosal pathogens of economic importance.
Technical Abstract: Direct-fed microbials (DFMs) are live microorganisms which confer a health benefit to the host. The mode of action of DFMs involves multiple mechanisms, including direct inhibition of enteric pathogens and indirectly through competitive exclusion of pathogens by the normal gut microbiota. Additionally, recent basic research efforts have focused on the effects of DFMs on promoting host immunity and on the complex interactions between the gut microflora and immune system development. This review will summarize the latest developments in DFM studies with particular emphasis on the underlying mechanisms of immune enhancement.