Cross-sectional study of Trichinella spp in pigs in CDR, Nepal using pepsin digestion and ELISA serology.

This epidemiological cross-sectional study was conducted in five major pig-producing districts of CDR, Nepal from November 2006 to April 2007. A total of 576 slaughtered pigs were randomly selected and diaphragmatic crus muscles (n = 551), corresponding sera (n = 487) and sera only (n = 25) were collected from them. Meat samples were examined by pepsin digestion to evaluate for larvae of Trichinella spp. The sera were investigated using ELISA to evaluate for antibodies against T. spiralis. The doubtful and positive sera from the ELISA test were investigated by end-point ELISA, and the Western blot was used for confirmatory diagnosis. Pepsin digestion did not detect the larvae of Trichinella spp. AB-ELISA showed 2 positive and 14 doubtful results, out of 344 sera analyzed. End-point ELISA and the Western blot had revealed that all 16 samples were truly negative. A questionnaire revealed no rodent control (70%), left over feeding practices (65%), dumping of farm waste (82.5%) and uncooked meat was being used as feed (100%). This study reveals that Trichinella spp has a low prevalence.

Microbial contamination of pig carcasses at a slaughterhouse in Vientiane capital, Lao PDR.

A cross-sectional study was conducted to determine microbial contamination of pig carcasses at a slaughterhouse in Vientiane, capital of Lao People Democratic Republic (Lao PDR). Between November 2004 and April 2005, 62 pig carcasses were randomly selected. From each carcass, pooled swabs (from "1" prior to and "2" after evisceration) and 25 g of tissue of mesenteric lymph nodes (MLN) were collected. The swab samples were examined for Aerobic Plate Count (APC) and Enterobacteriaceae Counts (EBC) and cultured for Salmonella. The lymph nodes were cultured for Salmonella only. Swabs1 and 2 had mean APC of 4.70 and 4.85 log10CFU/cm2, respectively. These two means were significantly (p = 0.0001) different. The means of EBC were 2.81 log10CFU/cm2 for Swab 1, and 2.98 log10CFU/cm2 for Swab 2. The difference were also statistical significant (p = 0.0001). The frequency of Salmonella isolation from Swab 1 was 46.8%, for Swab 2 was 66.1%, and from mesenteric lymphnodes was 53.2%. Eight different Salmonella serotypes were identified. The most frequent (29.1%) serotype was S. Rissen, followed by S. Anatum (26.2%), S. Derby (18.4%), and S. Elisabethville (8.7%). The other serotypes identified were S. Amsterdam (7.8%), S. Typhimurium (4.9%), S. Agona (2.9%), and S. Enteritidis (1.9%). Results of this study showed the levels of contamination with aerobic bacteria and Enterobacteriaceae were higher than recommended standards, and the carcasses were contaminated with Salmonella.