CategoryPre-Harvest Pork Safety
Date Full Report Received03/29/2005
Date Abstract Report Received07/26/2006
Funded ByNational Pork Board
Preventing pork associated foodborne diseases is important to pork producers. Infection with the parasite, Toxoplasma gondii (Tg), is a known risk factor associated with pork consumption. Thus assays that help producers find and eliminate such infections are needed. Current methods for Tg detection are based on serology and bioassays. These assays are dependent on time for serology, to get antibodies that are detectable, and on live animals for the expensive bioassays. The sensitive molecular assay for Tg DNA was developed to help producers and regulators to more easily test pork products for possible Tg contamination. Using high throughput techniques and improving this molecular assay could easily make the fluorogenic Tg DNA assay adaptable to work with miniaturized monitors to perform ante-mortem Tg tests. However, sensitivity and specificity of such assays, at the whole animal level, and in the final pork products, must be addressed.
Pork products were collected in markets nationwide in a statistically valid sampling under a separate USDA IFAFS grants by Drs. Hill and Dubey and their collaborators. Data reported here used the fluorogenic Tg DNA assay to check for Tg contamination of small aliquots from 226 pools representing 1180 pork products. The data showed 0/226 samples as positive for Tg DNA, indicating no or low level Tg contamination of these products. Further testing, directly comparing these DNA assay results with the well-established Tg bioassay in cats, and the meat juice antibody assay, is in process and should determine the validity of this molecular test. The combined results should show the actual level of Tg contamination in the nation’s pork products. Results using all of these assays should help affirm the actual low risk to the consumer of getting a foodborne Tg infection from the US pork supply. They will help assure our international trading partners of the high quality and safety of US pork products.