Start Date: May 06, 2006
End Date: Mar 20, 2011
1) Using a newly constructed (i.e., naive) commercial broiler production facility, we will follow bacterial, viral, protozoan, and fungal movement within the facility from prior to the first placement of birds through several successive production cycles. The movement of these organisms within the environment will be mapped using genetic identification and traditional culture methods. 2) Using a necrotic enteritis (NE) in vivo model developed in our laboratory and a primary cell culture model, we will investigate the interactions of Clostridium with other bacterial populations within the gastrointestinal tract of broilers and the development of NE. We will evaluate these bacterial populations using molecular-based techniques (DGGE, PFGE) in order to determine the dynamics between commensal gut bacterial populations and Clostridium. Additionally, we will examine the toxins produced by Clostridium using tissue culture techniques and Multiplex Polymerase Chain Reactions (PCR). 3) The efficacy of lactose, cottonseed and similar prebiotics and symbiotics will be evaluated under commercial conditions for their ability to reduce food-borne pathogens in poultry. Practical feeding trials will be performed to ascertain the ability of chlorate and alfalfa as alternatives to traditional antimicrobials, and the mode of action of these compounds will be determined. We will also study different quorum sensing autoinducers to determine the effects of biological and synthetic bacterial autoinducer inhibitors on poultry enteropathogens. 4) Utilizing an in vitro bacterial conjugation assay, we will identify flavophospholipol-like compounds (flavophospholipol has been shown to reduce horizontal gene transfer between Enterococci in vitro), that inhibit bacterial conjugation and resistance gene acquisition among gut bacteria. 5) We will characterize specific interactions between the immune and endocrine systems that influence enteropathogen colonization in the gastrointestinal tract of poultry. Microarrays will be utilized to assess fluctuations in key avian hormones that correspond to cytokine expression.