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The risk of bovine spongiform encephalopathy propagation was drastically reduced after the European Union (EU) Health Authorities adopted restrictions involving a ban on animal-derived proteins in the diet of farm animals. Currently, the EU's of cially recommended method for controlling meat and bone meal (MBM) in animal feed is the microscopic method, which involves the identi cation of bone fragments on the basis of their morphological characteristics. Recently, we demonstrated that a polymerase chain reaction (PCR)-based assay can be used for the detection of taxon-speci c DNA in MBM and animal feeds. To ensure the safe rendering of animal by-products, the EU Council requires that this material be treated at 1338C at 300 kPa for 20 min. Here we investigate the relationship between DNA degradation, PCR ampli cation, and MBM heat treatment. With a competitive PCR-based approach, we compare the ampli cation ef ciency of bovine mitochondrial DNA target sequences of different lengths in several heat-treated MBM samples. For our method, a synthetic competitive DNA is used as an internal control for both DNA extraction and PCR reaction. A correlation between an increase in treatment temperature and a reduction in the size of the target sequences suitable for ampli cation was observed, suggesting progressive DNA fragmentation due to the temperature. We show that short amplicons (147 bp) can be used to detect the presence of bovine mtDNA in MBM samples treated according to the current European regulations. The use of such a competitive approach to compare ampli cation ef ciency levels of targets of different lengths might represent a useful tool for the determination of both the amount of MBM in animal feeds and its proper heat treatment.There is evidence that bovine spongiform encephalopathy (BSE) was spread around the world through animal feed containing infected meat and bone meal (MBM) (3, 4). The effective preventive measures taken by the United Kingdom with the introduction of the so-called ''real feed ban'' in 1996 (a ban on animal proteins in farm animal feeds) have led to a rapid reduction in the appearance of new cases in that country (5). Based on such epidemiological evidence, national and international authorities (Of ce International des Epizooties, the World Health Organization, Codex Alimentarius, and the European Commission) have progressively implemented speci c legislation and guidelines regarding the appropriate heat treatment of MBMs (10), the ban of MBMs from ruminant feeds (6), and the removal of speci ed risk materials from slaughtered ruminants (8). Currently, there is a temporary ban on animal meal in feed for all animals intended for human consumption within the European Union (EU), allowing mem- ber states to improve the practical implementation of the European legislation to prevent the spread of BSE (9). Nevertheless, there is currently no reliable, sensitive, and speci c method to detect the presence of the BSE causative agent in feeds. Therefore, only indirect approaches testing...

Summary The relationship between Vibrio parahaemolyticus strains isolated from the aquatic environment and those isolated from cases of infection in humans is poorly understood due to the low prevalence of tdh‐ and/or trh‐positive strains in the environment. To address this concern, it would be useful to analyse the genetic relationships among environmental and food strains and with reference to clinical isolates, also applying molecular typing methods. The aim of this study was to evaluate the prevalence of toxigenic V. parahaemolyticus in Italian coastal waters and seafood, to examine intra‐species variability and to identify, using serotyping and pulsed‐field gel electrophoresis (PFGE), relationships among strains from different sources, geographical origin and period of isolation. Of the 192 V. parahaemolyticus strains isolated in different Italian areas and examined in this study, 25 (13.0%) proved to carry the trh gene while none of the strains proved positive to the search by PCR for tdh and Group‐Specific‐toxRS genes. The prevalence of toxigenic strains in the Tyrrhenian Sea was significantly lower than that calculated for the Ligurian coasts. Regarding the sources of isolation, the higher prevalence of trh‐positive V. parahaemolyticus was revealed in fish, followed by clams, plankton, oysters, mussels and lastly seawater. Within the toxigenic strains, 16 serotypes and 20 distinct PFGE patterns were identified. Two clusters, which included a total of 8 V. parahaemolyticus strains, were specifically associated with the North Adriatic Sea area and were stable over time. Our results demonstrate that trh‐positive V. parahaemolyticus strains circulated in Italy in the period 2002–2009 with a prevalence higher than that reported from other European and extra‐European countries, confirming that toxigenic V. parahaemolyticus is an emerging public health concern in Italy, regardless of its pandemic potential.

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