The effects of shot wounds on the hygienic conditions of pheasants (particularly those in the body cavity) were studied. Slaughtered (n = 33) and hunted pheasants (31 specimens with, and 33 specimens without shots in the body cavity) were stored uneviscerated at 0 and 4 degrees C. Specimens were taken at d 0, 3, 7, and 14. Hunted pheasants differed from slaughtered pheasants with respect to muscular hemorrhages and blood and fecal matter in the body cavity but also with regard to the presence of Escherichia coli in breast and thigh muscles. In addition, a higher thigh muscle pH (P < 0.05) was noted in hunted pheasants, with no significant (P > 0.05) increase observed during storage. Concentrations of biogenic amines in muscle tissue remained below the determination limit of 1 mg/kg for 90% of samples analyzed, with the maximum concentration for the remaining 10% of samples reaching 5.7 mg/kg, indicating a low incidence of contaminant bacteria. The observed changes in pH values and levels of biogenic amines failed to correlate with the presence or absence of shot lesions in the body cavity or abdominal region. Total aerobic counts increased significantly during storage, but the absolute numbers were consistently below 10(6) log(10) cfu/g. Although E. coli were <1 log(10) cfu/g in muscles of hunted pheasants on d 3 at 4 degrees C, counts of up to 3.7 log(10) cfu/g on d 7 at 4 degrees C indicated a loss of hygienic quality. Therefore, it is recommended that hunted, uneviscerated pheasants be stored 3 d at 4 degrees C, but not longer than 7 d after the hunt.

The final quality of fish meat depends on the chemical and microbiological quality of fish at the time of freezing as well as on other factors including storage temperature and freezing rate. Analysis of chemical composition (water, protein and fat content), expressible drip, total volatile nitrogen levels, microbiological analyses (total viable counts, Enterobacteriaceae, psychrotrophic bacteria) and histological examinations on dorsal skeletal muscles were carried out to distinguish fresh, frozen and double frozen rainbow trout (Oncorhynchus mykiss). Significantly higher expressible drip and total volatile base nitrogen concentrations (P < 0.05) were observed in frozen and double frozen trout, whereas chemical composition of fresh fish muscles was not significantly affected by freezing. The highest total viable counts, counts of Enterobacteriaceae and psychrotrophic bacteria were determined in double frozen trout. The light microscopy of fresh trout muscles did not show any microstructural changes, whereas deformations of muscle fibres and optically empty areas were found in frozen trout. Remarkable defects of the muscle structure in double frozen trout were demonstrated and total disruption of muscle fibres was found. The freezing of trout resulted in various structural changes in the dorsal skeletal musculature. This is a first study comparing changes in fresh, frozen and repeatedly frozen trout. Chemical, microbiological and subsequent histological examinations can be used for revealing the foul practices confusing the consumer with offering thawed fish instead of fresh cooled fish.

Little has been published about the occurrence, speciesidentification, andpathogenicpotentialofcoagulasenegative staphylococci (CoNS) present in drinking water. In this study, ten species were identified among 57 isolates of staphylococci from 756 samples of chlorinated drinking water taken from public distribution networks in the Slovak Republic. S. warneri (37%), S. haemolyticus (23%), and S. saprophyticus ssp. saprophyticus (14%) were identified most frequently. Isolates did not produce coagulase, DNase, or hyaluronidase; production of gelatinase and lecithinase was observed in 28 and 22 isolates, respectively. Genetically encoded ability for production of enterotoxin SED was revealed in two isolates. Among ten antibiotics tested, resistance to ampicillin (66.7%), penicillin (64.9%), and erythromycin (57.9%) were observed most frequently. Resistance to gentamicin, vancomycin, or clindamycin was not confirmed. Production of β-lactamase was observed in 64.9% of isolates. Fourty-two isolates were resistant to two or more antibiotics tested, and eight isolates showed multiresistance. The presence of mecA gene was confirmed in 8 isolates, while PBP2a was revealed in 7. Two isolates of S. epidermidis were identified as methicillin-resistant (MRSE). The results demonstrate that CoNS in chlorinated drinking water may possess virulence factors and show resistance to various antibiotics. Therefore, their pathogenic potential should not be ignored.

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This study confirmed the need of monitoring antimicrobial resistance in coagulase-negative staphylococci not only in the meat of slaughter animals but also in retail marine fish. The results showed that MALDI-TOF mass spectrometry is useful, accurate, and rapid method for species identification of food pathogens including Staphylococcus spp.

MIŽÁKOVÁ A., PIPOVÁ M., TUREK P. (2002): The occurrence of moulds in fermented raw meat products. Czech J. Food Sci., 20: 89-94.The consumption of food contaminated with moulds (microscopic filamentous fungi) and their toxic metabolites results in the development of food-borne mycotoxicosis. The spores of moulds are ubiquitously spread in the environment and can be detected everywhere. In this study, the presence of various moulds was determined in pork and beef used as a raw material, in salami emulsions, as well as in five kinds of fermented raw meat products. Penicillium sp., Acremonium sp., Mucor sp., Cladosporium sp., and Aspergillus sp. were the most frequently isolated genera of moulds. Flavourings added to meat during the production of fermented raw meat products were heavily contaminated with moulds. The widest spectrum and the highest counts of microscopic filamentous fungi were observed in the following spices: milled black pepper, nutmeg, garlic powder and crushed caraway. The level of contamination depended upon the season, being higher in the summer months.

The objective of this study was to screen Lactobacillus plantarum strains isolated from the traditional Slovak raw sheep milk cheese for their inhibitory potential. Seventy-two strains were obtained from samples of raw sheep milk and raw sheep milk cheeses collected from April 2017 to September 2018, in 23 geographical areas of Eastern Slovakia, by inoculation of de Man, Rogosa, and Sharpe agar plates (Oxoid, Basingstoke, UK). Using both the genus-and species-specific PCR methods, 43 strains were identified as Lactobacillus spp., and 10 strains were confirmed as Lb. plantarum. First, the whole bacterial cultures of Lb. plantarum strains were tested by disc diffusion assay. All showed very good antibacterial activities against 6 selected foodborne pathogens, including Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus. Then, cell-free neutralized supernatants and partially purified bacteriocins were prepared from the 4 Lb. plantarum strains that exhibited the best antibacterial potential, and they were tested the same way as the whole bacterial cultures. Seven of the 10 Lb. plantarum strains harbored the plnEF gene, 3 strains harbored the plnD gene, and 2 strains possessed both the plnA and plnC genes that encode the production of the respective plantaricins. The presence of both plnR and plnL genes was only detected in a single Lb. plantarum isolate. Based on the results of this study, 4 strains of Lb. plantarum appeared to be suitable candidates for further testing in the dairy manufacturing sector, particularly in the production of raw sheep milk products.

The aim of this study was to determine susceptibility of species-identified coagulase-negative staphylococci (CoNS) isolated from the thigh muscles of hunted wild pheasants (Phasianus colchicus) to seven antibiotics (penicillin, tetracycline, erythromycin, ampicillin, oxacillin, gentamicin, and vancomycin) with the help of agar dilution method. Genus confirmation of each isolate was based on the analysis of PCR product obtained from DNA target 16S ribosomal DNA. Species-identification of staphylococci was performed by means of matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) based on bacterial protein profiling. From the results of this study it follows that 41 strains of CoNS were isolated from the meat of wild pheasants. The following species of staphylococci were identified by MALDI-TOF MS: S. epidermidis (17 strains), S. warneri (8 strains), S. haemolyticus (5 strains), S. hominis (4 strains), S. xylosus (3 strains), S. vitulinus (2 strains), S. pasteuri (1 strain) and S. arlettae (1 strain). Based on results of the agar dilution method, resistance to penicillin was detected most frequently (96.2%). On the contrary, 100% susceptibility to vancomycin was observed among isolates of CoNS. Moreover, each out of 41 isolates showed simultaneous resistance to at least two antibiotics tested.