Short communication: Enterotoxigenic potential of coagulase-negative staphylococci isolated from bovine milk in Poland.

Our objective was to assess the enterotoxigenic potential of coagulase-negative staphylococci (CNS) isolated from bovine milk in Poland. We analyzed CNS isolates collected from 133 bovine milk batches from dairy farms in the Western Pomerania district during 2 milking seasons. A total of 163 isolates were screened by multiplex/duplex PCR for the presence of 18 of 25 enterotoxin genes identified so far in Staphylococcus aureus. The CNS strains presumed to be potentially enterotoxigenic were identified at the species level based on MALDI-TOF mass spectrometry analysis. Based on the presence of an amplicon matching D, G, or O enterotoxin genes, we initially identified 32 of the 163 CNS isolates tested as potentially enterotoxigenic. However, only 8 of these strains were confirmed as such. All 8 of these CNS strains, identified as Staphylococcus haemolyticus, harbored the seg genes, a prerequisite for enterotoxin G production, but so far not connected with staphylococcal foodborne poisoning cases. None of the CNS bovine milk isolates tested was a potential producer of classical A to E staphylococcal enterotoxins. Results of our surveys revealed a low prevalence of enterotoxigenic CNS among the milk isolates from dairy farms in the Western Pomerania district, Poland, suggesting that they pose only a mild health risk in milk. In our opinion, confirmed formation of nonspecific amplicons leading to false-positive results excludes multiplex/duplex PCR as the sole method for assessing the enterotoxigenic potential of CNS.

Campylobacter spp. in waters of three main western Pomerania water bodies.

Campylobacters are responsible for increasing numbers of gastroenteritis cases in humans as well as miscarriages and diarrhea in farm and domestic animals. Surface waters are potential reservoirs and transmitting vehicles for these bacteria. Subject of analysis were surface water samples collected from the River Odra, Szczecin Lagoon and the Pomeranian Bay in monthly or bimonthly intervals, starting from April 1998. Analysis directed on campylobacters included enrichment in Preston broth prior to plating on CCDA isolation medium and identification, to the species level, by the api CAMPY tests. The detection level of the method was 1 CFU/10 ml. Numbers of total and faecal coliforms were counted according to the national standards. In addition water temperature and water saturation with oxygen were measured. Presence of Campylobacter spp., at the level detectable by the method applied, was confirmed in 19.7% of the Odra River, 5.6% of the Szczecin Lagoon and 0% of the Pomeranian Bay surface water samples. The contamination level of the Campylobacter--positive surface water samples did not exceed 10 CFU/ml. Isolation frequency depended on water purity class, counts of total and faecal coliforms and sampling site (p < 0.01). Species dominating in the River Odra and Szczecin Lagoon surface waters were C. jejuni ssp. jejuni and C. coli, respectively.