| Summary: | <i>Salmonella</i> is one of the most important zoonotic pathogens worldwide. Swine represent typical reservoirs of this bacterium and a frequent source of human infection. Some intrinsic traits make some serovars or strains more virulent than others. Twenty-nine <i>Salmonella</i> spp. isolated from pigs belonging to 16 different serovars were analyzed for gastric acid environment resistance, presence of virulence genes (<i>mgtC</i>, <i>rhuM</i>, <i>pipB</i>, <i>sopB</i>, <i>spvRBC</i>, <i>gipA</i>, <i>sodCI</i>, <i>sopE</i>), antimicrobial resistance and presence of antimicrobial resistance genes (<i>bla<sub>TEM</sub></i>, <i>bla<sub>PSE-1</sub></i>, <i>aadA1</i>, <i>aadA2</i>, <i>aphA1</i>-lab, <i>strA-strB</i>, <i>tetA</i>, <i>tetB</i>, <i>tetC</i>, <i>tetG</i>, <i>sul1</i>, <i>sul2</i>, <i>sul3</i>). A percentage of 44.83% of strains showed constitutive and inducible gastric acid resistance, whereas 37.93% of strains became resistant only after induction. The genes <i>sopB</i>, <i>pipB</i> and <i>mgtC</i> were the most often detected, with 79.31%, 48.28% and 37.93% of positive strains, respectively. <i>Salmonella virulence plasmid</i> genes were detected in a <i>S</i>. <i>enterica</i> sup. <i>houtenae</i> ser. 40:z<sub>4</sub>,z<sub>23</sub>:-strain. Fifteen different virulence profiles were identified: one isolate (ser. Typhimurium) was positive for 6 genes, and 6 isolates (3 ser. Typhimurium, 2 ser. Typhimurium monophasic variant and 1 ser. Choleraesuis) scored positive for 5 genes. None of the isolates resulted resistant to cefotaxime and ciprofloxacin, while all isolates were susceptible to ceftazidime, colistin and gentamycin. Many strains were resistant to sulfonamide (75.86%), tetracycline (51.72%), streptomycin (48.28%) and ampicillin (31.03%). Twenty different resisto-types were identified. Six strains (4 ser. Typhimurium, 1 ser. Derby and 1 ser. Typhimurium monophasic variant) showed the ASSuT profile. Most detected resistance genes <i>sul2</i> (34.48%), <i>tetA</i> (27.58%) and <i>strA-strB</i> (27.58%). Great variability was observed in analyzed strains. <i>S</i>. ser. Typhimurium was confirmed as one of the most virulent serovars. This study underlines that swine could be a reservoir and source of pathogenic <i>Salmonella</i> strains.
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