Comparison of a Modified Digestion Assay with Trichinoscopy for the Detection of Trichinella Larvae in Pork

Abstract

A pepsin-HCl digestion assay and two compressorium techniques (trichinoscopy) for the identification of swine muscle tissue containing low levels of Trichinella larvae were compared as part of the test validation process for quality assurance purposes. Compressoria read with a stereomicroscope detected more larvae (P < 0.0001, n = 57) and more tissues (P = 0.0047, n = 57) than did compressoria read with a projection microscope (trichinoscope). The digestion assay evaluated was 3.2 times as likely as the best compressorium technique to identify a positive tissue when these procedures were used to test 1 g of infected muscle (P < 0.001; 95% confidence interval for the odds ratio, 2.0 to 5.4; n = 161 and n = 189, respectively). Detection by trichinoscopy improved as the number of larvae in tissues increased to > 2 larvae per g, but trichinoscopy was less sensitive than the digestion assay regardless of the tissue larval load. These data indicate that the quality controlled digestion assay used in this study is more sensitive than trichinoscopic techniques in the detection of tissues containing low levels of Trichinella larvae.

Detecting Trichinella infections using inverse microscopy and an improved larval counting technique

“…Kö hler, 1978;Prost & Nowakowski, 1990;Gamble, 1999;Forbes & Gajadhar, 1999;Forbes et al, 2005;Rossi & Pozio, 2008). Kö hler, 1978;Prost & Nowakowski, 1990;Gamble, 1999;Forbes & Gajadhar, 1999;Forbes et al, 2005;Rossi & Pozio, 2008).…”

Trichinellosis in Serbia and possibilities to improve control measures

“…Pig meat samples can be examined by trichinoscopy and/or artificial digestion at licentiate veterinary services according to official regulations (Official Gazette RS for the current year). However, the low sensitivity of trichinoscopy as a diagnostic method and the possibility of missing non-encapsulated Trichinella (Forbes et al 2003) contribute to less reliable data about prevalences of Trichinella spp. in Serbia.…”

Components of control for foodborne parasites and their application in the food production chain

“…Although predilection sites vary according to host species, the tongue and the diaphragm are often among the preferred sites. Trichinoscopy, another direct method used historically, is less sensitive than digestion and is not recommended for food safety testing (Forbes et al, 2003;OIE, 2014b). An ISO standard for this method (ISO/DIS 18743) is also currently under development and should be available in the near future.…”