Fontes de contaminação de Staphylococcus coagulase positiva e Yersinia enterocolitica no fluxograma de abate de suínos

Abstract

Staphylococcus coagulase positive and Yersina enterocolitica are important pathogens related to cases of foodborne illness associated with pork consumption, respectively. The aim of this study was to track coagulase-positive Staphylococcus and Yersinia enterocolitica in pig slaughtering flowchart and identify their sources of contamination. For the search of coagulase-positive Staphylococcus, four pigs from 10 different lots were monitored during slaughter. Samples were collected from the holding pens before the arrival of the animals. Surface samples were collected after dehairing, after evisceration, before the cold chamber, in addition to stool samples in the rectum animals immediately after stunning, mesenteric limph nodes, tongues and jowls. For the search of Yersinia enterocolitica, 60 pigs of 15 bays of a pig farm in Rio Grande do Sul. Stool samples were collected directly from the rectum. Surface samples were collected after dehairing, after evisceration, before the cold chamber and jowls. Samples from the scalding tank water before and after the passage of animals were collected too. The isolates were obtained through microbiological analysis and PCR. The similarity of the strains was compared through rep-PCR. Coagulase-positive Staphylococcus was isolated from 40% of the holding pens. Lymph nodes were further isolation point (19%), followed by cold chamber (17.8%), rectum (16.1%) after evisceration (16.1%), jowls (12.5%), after dehairing (8.9%) and tongue (8.9%). From the results, it can be concluded that the holding pens are important sources of SCP contamination for swine, which once contaminated, can disseminate the microorganism in the slaughter flowchart through the feces, mesenteric lymph nodes and oral cavity. This is the first study in Brazil that shows that the holding pens are important sources of SCP contamination for pigs sent to slaughter. Yersinia enterocolitica was isolated from three bays in the pig farm (20%) and from 20 samples (6.67%) obtained in the flowchart. The jowl was the point of greatest isolation (30%), followed by after dehairing (25%), the cold chamber (20%), after evisceration (15%) and rectum (10%). No isolates were obtained from the scalding tank water. After the rep-PCR it was observed that contaminated pigs on the farm can carry the microorganism to other points in the slaughter flowchart. However, the sources of contamination are in the slaughterhouse. The jowls and the carcass at the entrance to the cold chamber are the most critical points. The measures of good practices adopted in the hygiene of the pre-slaughter holding pens, as well as those adopted during the slaughter flow chart, if inefficient, may allow the persistence of coagulase positive Staphylococcus and Yersinia enterocolitica in the final product, respectively, constituting a risk to public health.