Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 10/20/2007
Publication Date: N/A
Technical Abstract: The objective of this study was to compare the prevalence of Clostridium difficile among different age and production groups of swine in a vertically integrated swine operation in Texas in 2006. Isolation of C. difficile was performed utilizing an enrichment technique and restrictive media. Preliminary results are based on 98 C. difficile isolates arising from 978 swine fecal samples. The prevalence of C. difficile was significantly different between the groups (p<0.001), and was highest among piglets at 39.0% (95% Confidence Interval: 30.1, 48.4), followed by 17.0% (11.2, 24.3) for farrowing sows, 7.8% (3.6, 14.2) for nursery, 3.6% (2.0, 6.0) for grower-finisher, 2.8% (0.90, 6.3) for breeding boars and sows, and there were no positive samples from pork products. Isolates were tested for Toxins A and B using commercial ELISA kits and the presence of the toxins was verified using PCR. PCR also was used to test for the presence of the tcdC gene deletion. The tcdC gene is a regulator gene that codes for toxin production and a deletion in this gene causes increased virulence. To date, PCR has been run on 35 isolates and indicate that all of these isolates harbor the tcdC gene deletion. Genomic comparisons to human and swine isolates from the CDC will be made using both PCR and pulse-field gel electrophoresis. In this study we found C. difficile most commonly originated among farrowing barn production types (piglets, farrowing sows) and not in grower/finisher production. Relatively low prevalence in late production suggests a low food safety risk; however, the isolates of C. difficile in our study are considered more virulent because of the tcdC gene deletion, and similar isolates have been linked to outbreaks of C. difficile in hospitals of North America and Europe.