Detection of Trichinellosis in Pigs by Artificial Digestion and Enzyme Immunoassay

Abstract

The objective of this study was to demonstrate the reliability of current and proposed methods for the inspection of swine and other species for infection with the parasite Trichinella spiralis. Five groups of pigs were infected with doses of 2500, 500, 100, 50, and 20 T. spiralis larvae to establish moderate and low-level infections. Pigs were bled periodically during the study for samples to be tested by enzyme immunoassay (EIA). At the conclusion of the study, pigs were slaughtered and tissues collected for analyses of worm burdens and for comparison of digestion testing methods. Comparisons of pooled sample digestion methods were made using inspection methods prescribed by European Union Directives and the USDA, Code of Federal Regulations. Pooled sample digestion testing using 1-g samples was effective for detecting pigs with larval densities of > 10 larvae per gram (LPG) of tissue but only partially effective for pigs with infections of <3 LPG. Pooled sample digestion testing using 5-g samples detected all pigs with infection levels > 1 LPG. The EIA detected all T. spiralis-infected pigs, but did not detect infections in some pigs until 49 days after inoculation. These results demonstrate that the pooled sample digestion method using a 5-g sample size is the most effective inspection method for reducing the risk of human exposure to T. spiralis in pork.

Infectivity ofTrichinellaspp. recovered from decaying mouse and fox muscle tissue

“…O utbreed laboratory mice (Ssc: CF1) and farm bred red foxes (Vulpes vulpes) were orally inoculated with nine different Trichinella genotypes (doses: 500 larvae/mouse and 10.000 larvae/fox) obtained from the Trichinella Reference Centre (Rome) (Pozio et al, 1989 to six weeks of storage the muscle larvae (ML) were recovered from the meat samples by digestion according to Gamble (1996). A control sample (day 0) was digested immediately after mincing.…”

“…to six weeks of storage the muscle larvae (ML) were recovered from the meat samples by digestion according to Gamble (1996). A control sample (day 0) was digested immediately after mincing.…”

Localization ofTrichinella spiralisin muscles of commercial and parasitologic interest in pork

“…Distribution of T. spiralis larvae in each tissue sample was determined by digestion of 100 g of tissue (Gamble, 1996).…”

Detection of Experimental Swine Trichinellosis Using Commercial Elisa Test

“…Literature data confirm the value of E-S ELISA for the detection of trichinellosis in pigs (Gamble et al 1983, Smith 1987, Smith 1988, Smith and Snowdon 1989, van der Leek et al 1992, Nöckler et al 1995, Gamble 1996, Gamble 1998, Kapel et al 1998, Reiterová et al 1999, Kapel and Gamble 2000, Nöckler et al 2005, Kořínková et al 2008). The authors of the studies cited above applied the E-S ELISA to detect experimental swine trichinellosis induced by varying infection doses of T. spiralis larvae (50, 100, 200, 500, 1000, 1500, 3000, 5000, 8000, 10 000, 15 400, 20 000, 64 000).…”

“…Our findings indicate that the highest intensity of T. spiralis infection occurred in the diaphragm. A large number of authors have identified swine diaphragm and tongue as equally valuable research material for T. spiralis muscle larvae detection (Kotula et al 1984, Gamble 1996, Forbes and Gajadhar 1999, Serrano et al 1999. In the present study T. spiralis infection intensity averaged to 24.30 larvae/g in the tongue, which was significantly lower (53%) than in the diaphragm (46.18 larvae/g = 100%).…”