Development of A System to Evaluate Impact of On-farm Antimicrobial Use On Swine Health and On Emergence of Antimicrobial Resistant Bacteria of Swine Origin

The overall objective of the study here is to assess, for the first time in quantitative terms, the impact of the new FDA regulations addressing the use of medically important antibiotics in food animals on the animal health and on the prevalence of AMR bacteria in swine. Our hypothesis is that changes in the veterinary use of antibiotics may have an impact on the occurrence of respiratory and/or enteric diseases in swine, and that it may also impact the frequency of isolation of AMR bacteria from swine samples. In order to test this hypothesis, research- and implementation-oriented activities will be conducted to achieve partial sub-objectives. Specificallya) RESEARCH a.1. Establish baseline patterns of submissions of samples associated with respiratory and enteric diseases (i.e., tissue, feces) to the Minnesota Veterinary Diagnostic Laboratory (MVDL) in a 11-year period prior to the effective date of the new FDA regulations (2006-2016), and monitoring of these patterns between
January 2017 until the end of the project (October 2018).a.2. Determine the frequency of detection of relevant respiratory (Haemophilus parasuis, Streptococcus suis, Pasteurella multocida, Actinobacillus suis, Mycoplasma hyopneumoniae, M. hyorhinis) and digestive (beta-hemolytic Escherichia coli, Salmonella enterica, Brachyspira spp., Lawsonia intracellularis) bacterial pathogens from clinical samples received at the MVDL before (2006-2016) and after (2017-Oct 2018) the effective date of the FDA new regulations.a.3. Evaluate the patterns of AMR found in bacterial pathogens routinely subjected to antibiotic susceptibility testing (E. coli, S. enterica, P. multocida, S. suis, H. parasuis) at the MVDL in the 2006-2016 and 2017-2018 periods.B IMPLEMENTATION (translation of research):B.1. Develop a production system-oriented monitoring system to evaluate the trends in antibiotic and mineral on-farm use, as well as the prevalence of AMR bacteria recovered from clinical samples originated in
each system in collaboration with volunteering swine production companies. This system will cover records collected before and after the effective date of the FDA new regulations.Achievement of those objectives will allow the comparison of i) the patterns of submission of clinical samples associated with respiratory and enteric diseases, ii) the frequency of isolation of relevant respiratory and digestive bacterial pathogens from swine samples and ii) the prevalence of AR-bacteria among relevant swine pathogens, thus providing information on the potential impact of changes in veterinary use of antibiotics in swine in Minnesota. Finally, knowledge gained through this research will be translated through the implementation of a monitoring system to assess the evolution of AMR in the swine industry.