4d.Progress report.
This report serves to document research conducted under a Specific Cooperative Agreement between ARS and The Pennsylvania State University. Additional information can be found in the reports for the SCAs with the other universities involved in the project (1265-32000-078-01S, 02S, and 04S) and in the report for the parent project 1265-32000-078-00D "DAIRY MANAGEMENT PRACTICES AND THE TRANSMISSION OF ZOONOTIC PATHOGENS IN MILK". This cooperative agreement is part of a larger project involving 4 universities, the University of Pennsylvania, The Pennsylvania State University, University of Vermont, and Cornell University, and formulated in consultation with the Northeastern Regional Dairy Quality Alliance (RDQMA) and the National Milk Producers Federation. Currently, this project provides longitudinal access to three dairy herds totaling 575 milk cows (NY herd-340 milk cows; PA herd-110 milk cows and VT herd-125 cows). Fecal samples from adult cows on the PA farm are collected twice a year and sent to collaborating labs to be tested for the presence of Mycobacterium avium Paratuberculosis (MAP, the causative agent of Johne's disease), and the zoonotic foodborne bacterial pathogens Salmonella, Escherichia coli, Listeria monocytogenes, Campylobacter, and Enterococcus. Blood serum is collected quarterly to test for the presence of antibodies to the Johne's Disease (JD) organism. Environmental samples of manure, feed, water, vermin, birds, flies, etc are taken 4 times a year for analysis by collaborators. Samples of bulk tank milk and milk filters are taken weekly. The purpose of the project from the perspective of our lab is to characterize the microbial populations on the farm with particular interest in Salmonella, Escherichia coli, and Listeria monocytogenes. Initial findings from the PA farm demonstrated an outbreak of Salmonella and this organism was frequently detected in the milk filter and occasionally in bulk tank milk. The rate of fecal and environmental sampling was increased to fully document the outbreak. Sampling continues at the increased rate. Several serotypes of Salmonella have been detected. The milk filter was shown to be an indicator of the rate of Salmonella shedding within the herd. In addition, MAP has been found in fecal and environmental samples. Milk samples from all three farms have been analyzed for general quality indicators.