Ann. Méd. Vét., 2002, 146 (6), pp 353 - 360 Ecology of Salmonella in slaughter pigs digestive tract and study of the contamination of carcassesBOUDRY C., KORSAK N., JACOB B., ETIENNE G., THÉWIS A., DAUBE G.Abstract :
This article presents a study on the Salmonella asymptomatic carriage of finishing pigs and its consequences on the contamination of carcasses. Twenty finishing pigs were followed to determine the faecal shedding of Salmonella. No sample was positive but at the slaughter-house, the analysis of tonsils and certain parts of the digestive tract (mesenterial lymph nodes, ileum and large intestine content) revealed that 70 % of the pigs were positive. The strains isolated from the faecal samples of the large intestine and from tonsils were identical, which might indicate that there has been an oral contamination from pig to pig due to the shedding of Salmonella or a carriage of different strains in different organs. The mesenterial lymph nodes (40 % positive) were contaminated by strains which were different from those from the faecal samples and tonsils. Salmonella strains were only found on the swabs of one carcass. A complementary assay has shown the negative role played by the scalding step. This latter may contaminate the oral and rectal cavities of slaughtered animals. This entire study reveals the difficulty to predict the contamination risk at the slaughterhouse from the analysis of finishing pigs faecal samples. Therefore, a better knowledge of the carriage and the shedding of Salmonella during the finishing period and during the slaughter is necessary to minimise meat contamination. Get the PDF Contact person : nkorsak@ulg.ac.be |