Location: Food and Feed Safety Research
Project Number: 3091-32000-035-000-D
Project Type: In-House Appropriated
Start Date: Mar 17, 2016
End Date: Mar 16, 2021
Objective:
Objective 1: Define the differential host-pathogen interactions between Salmonella and chicken and poultry mucosal immune systems using genomic technologies. Determine the relationship between foodborne pathogens and the mucosal innate immune response, focusing on epigenetic reprogramming of host immune genes in persistent infections.
Objective 2: Identify and develop key strategies including waste, vaccination (using innate immunity), and lighting management strategies for use at animal production facilities that mitigate and reduce the bacterial load of Salmonella and other foodborne pathogens without the use of antibiotics during pre-harvest production in broiler chickens and turkeys.
Objective 3: Analyze and characterize both host and Salmonella proteins that are modulated in expression during infection using quantitative proteomic. Develop strategies to reduce foodborne pathogens by targeting host immune-metabolic signaling pathways affected by Salmonella and Campylobacter virulence factors.
Objective 4: Investigate potential alternatives to antibiotics, such as chitosan preparations and other commercially available products, on the cecal levels of Salmonella and Campylobacter using an experimental model and metagenomics. Investigate the potential for use and the mechanism used by specific nutritional supplements to inhibit the transfer of genetic resistance elements, such as plasmids, by conjugation between commensal and foodborne bacteria.
Objective 5: Investigate the interaction between yeast and fungi and foodborne bacteria to determine their role as commensals and inhibitors or their use as alternatives to antibiotics as pre-and probiotics.
Objective 6: Identify ecological reservoirs of pathogens and the potential role of dispersal of animal waste that enable the retention of foodborne pathogens within animal production facilities and the surrounding environments.
Approach:
The Centers for Disease Control and Prevention continues to monitor multistate foodborne outbreaks that impact health of the nation over the last 10 years. One area of concern is the reduction of Salmonella as a foodborne pathogen. Despite control efforts that cost over a half a billion dollars annually, foodborne illnesses due to Salmonella continues to impact the consumer. Poultry are commonly identified as a major source of Salmonella. To develop urgently needed new control strategies against Salmonella, we will take a multi-faceted, but integrated approach to identify and evaluate factors at the pre-harvest level that can be used. Based on previous research and collaborations with industry, we will identify and modify management practices that may decrease foodborne pathogen load, as well as environmental conditions associated with higher risk that would be conducive to pathogen survival and growth. Cost effective alternatives will be suggested throughout the poultry production phase. Environmental areas of concern, such as poultry waste and insect vectors will be included. At a more micro-level, interactions among fungi, protozoa, and other microbes will be evaluated under commercial production practices with the outcome of proposed new strategies for pathogen reduction. Campylobacter, a foodborne pathogen in poultry, has become an increasing concern due to the development of antibiotic resistance, especially to fluoroquinolones. The proposed research will investigate strategies to reduce pre-harvest Campylobacter, which will enhance the microbiological safety of poultry. This is important for food safety, but also for the reduction of potential antimicrobial resistance in animal agriculture and public health. Immune modulation is one approach for new anti-infective therapies, whereby natural mechanisms in the host can be exploited to strengthen therapeutic benefits. The stimulation of innate immunity has considerable potential to induce a profound and rapid cross-protection against multiple serovars of bacteria. Using "omic" techniques, including functional genomics, epigenetics, proteomics, and metabolomics, we will identify effective modulators of innate immunity to control infections, especially in situations where vaccination is not appropriate. Furthermore, metabolism and host immunity are essential requirements for survival. Mounting an immune response requires major changes to metabolic processes. Thus, the integration of central metabolic pathways and nutrient sensing with antibacterial immunity alters cellular energy homeostasis and contributes to the prevention or resolution of infectious diseases. Hence, immune and metabolic response processes govern infectious diseases. Research taken will focus on obtaining a greater understanding of the critical nodes of immunometabolism during Salmonella and Campylobacter infection.
