#15-170

Complete

Date Full Report Received

Date Abstract Report Received

08/14/2018

Investigation

Institution: , ,
Primary Investigator:

The objective of the study was to complete a national serological survey in market weight slaughter pigs and sows to determine the seroprevalence of Toxoplasma gondii and T. spiralis in these two populations comprising the national swine herd. We have established seroprevalence of these pathogens as measured in a statistically valid animal level sampling at slaughter in the 50 largest (by volume) plants for market hogs and in the 7 largest sow-only plants in the U.S. The survey encompassed 95% of slaughter production in the U.S., and now provides the most current national dataset for T. gondii and T. spiralis seroprevalence in market pigs destined for the fresh meat case and sows destined for processed meat products. We used sera collected at the slaughter plants and two commercially available, USDA validated ELISA assays to detect T. gondii and T. spiralis positive samples; all T. gondii ELISA positive samples were retested using the modified agglutination test (MAT). The survey provides a measure of the current national seroprevalence of T. gondii and T. spiralis infections in market pigs and sows, and provides evidence of the impact of industry-led changes in swine management on reduction of these zoonotic pathogens in the U.S. commercial pork supply. In 40,164 market hogs tested for the presence of antibody to T. gondii, seroprevalence was found to be 2.3%, while in 13,000 sows, seroprevalence was measured at 4.1%. Testing of the samples for the presence of antibody to T. spiralis using a commercial ELISA test kit detected no Trichinella positive samples in any of the 53,164 samples tested.