RAW MILK AT VENDING MACHINES: EVALUATION OF E. SAKAZAKII, COXIELLA BURNETII AND M. PARATUBERCULOSIS IN PIEDMONT EXPERIENCE

Italian consumers changed their food habits in the last period; the increase of raw milk consuming is also related to the high number of self service vending machines that have been authorized, particularly in Northern Italy. According to national rules on raw milk hygienic conditions, the most important bacteria are checked by Veterinary Services; the aim of this study was to investigate some emerging or re-emerging hazards in raw milk at vending machines. For this reason 100 raw milk samples were collected and analyzed in order to detect E. sakazakii, Coxiella burnetii and M. avium subsp paratuberculosis. One milk sample resulted to be positive with PCR method for E. sakazakii (no cultural confirmation was possible); 49% of samples resulted posivite for the presence of Coxiella burnetii specific DNA, and 5% of milk samples came out positive to the presence of M. paratuberuclosis antibodies with ELISA methods

Differentiation of five tuna species by a multipex primer-extension assay

A novel methodology based on analysis of mtDNA-cytb diagnostic sites was performed to discriminate four closely related species of Thunnus (Thunnus alalunga, Thunnus albacares, Thunnus obesus and Thunnus thynnus) and one species of Euthynnus (Katsuwonus pelamis) genus in raw and canned tuna. The primers used in the preliminary PCR designed in well conserved region upstream and downstream of the diagnosis sites successfully amplified a 132 bp region from the cytb gene of all the species taken into consideration. The sites of diagnosis have been interrogate simultaneously using a multiplex primer-extension assay (PER) and the results were confirmed by fragment sequencing. The applicability of the multiplex PER assay to commercial canned tuna samples was also demonstrated. The proposed test could be useful for detection of fraud and for seafood traceability

Comparison of Lactococcus garvieae strains isolated in northern Italy from dairy products and fishes through molecular typing

AIMS: To investigate the genetic relatedness between Lactococcus garvieae strains isolated from fish and dairy samples collected in northern Italy, using random-amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR), Sau-PCR and amplified fragment length polymorphism (AFLP). METHODS AND RESULTS: Eighty-one isolates from bovine and caprine dairy products (n = 53) and from diseased rainbow trouts and other fishes (n = 28) were examined. All methods showed a typeability of 100%, repeatability ranging from 84.4% to 97.5% and discriminatory powers from 0.798 to 0.986. Dairy and fish strains revealed a low genetic relatedness as they are often grouped into distinct clusters. RAPD analysis discriminated 52 genotypes when primer M13 was used, whereas with primer P5 only 27 genotypes were identified. When Sau-PCR was performed, 13 genotypes were detected while AFLP analysis allowed the differentiation of 32 genotypes. CONCLUSION: L. garvieae strains isolated from dairy samples are generally not related to those collected from fish lactococcosis outbreaks. Significance and Impact of the Study: L. garvieae strains exhibit a genetic diversity related to the specific animal host they colonize. RAPD M13 fingerprinting proved to be a molecular tool for comparing isolates, whereas Sau-PCR and AFLP analyses were useful techniques to investigate the distribution of L. garvieae populations in the environment