| Summary: | Livestock-associated methicillin-resistant <i>Staphylococcus aureus</i> (LA-MRSA) remains a serious public health threat. Porcine nasal cavities are predominant habitats of LA-MRSA. Hence, components of their microbiota might be of interest as putative antagonistically acting competitors. Here, an extensive culturomics approach has been applied including 27 healthy pigs from seven different farms; five were treated with antibiotics prior to sampling. Overall, 314 different species with standing in nomenclature and 51 isolates representing novel bacterial taxa were detected. <i>Staphylococcus aureus</i> was isolated from pigs on all seven farms sampled, comprising ten different <i>spa</i> types with t899 (<i>n</i> = 15, 29.4%) and t337 (<i>n</i> = 10, 19.6%) being most frequently isolated. Twenty-six MRSA (mostly t899) were detected on five out of the seven farms. Positive correlations between MRSA colonization and age and colonization with <i>Streptococcus hyovaginalis</i>, and a negative correlation between colonization with MRSA and <i>Citrobacter</i> spp. were found (<i>p</i> < 0.05). Of 209 non-<i>S. aureus</i> members of the <i>Staphylococcaceae</i> family, 25 isolates (12.0%) from three out of the seven farms exhibited methicillin resistance, including two <i>Macrococcus goetzii</i> isolates carrying the <i>mecB</i> gene. Among 125 <i>Enterobacterales</i>, none tested positive for extended-spectrum beta-lactamase (ESBL) and carbapenemase production. The high frequency of methicillin-resistant staphylococci supports the need for enhanced efforts within the “One Health” concept to manage the antibiotic resistance crisis in the human and veterinary medicine sector.
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