###### Abstract  
The prevalence of staphylococci in the environment of humans, including food, may lead to the production of toxins and food poisoning in consumers. Additionally, staphylococci constitute a reservoir of genes determining antibiotic resistance. The study aimed to compare the antibiotic resistance and biofilm-forming ability of staphylococci isolated from bulk tank milk and assess the occurrence of animal-associated methicillin-resistant _Staphylococcus aureus_. The study consisted of isolation of strains from cow milk, confirming their belonging to _Staphylococcus_ sp. and _S. aureus_, investigation of the presence of a gene determining the production of coagulase, and genes determining resistance to \(\beta\)-lactams, tetracyclines, vancomycin, natural penicillins, and aminopenicillins, as well as virulence genes determining biofilm production. There were 56 bacterial strains isolated, which belong to _Staphylococcus_ sp. All isolates showed resistance to amoxicillin, erythromycinomycin, and tetracycline. The lowest resistance was demonstrated for vancomycin (48.2%). The _mccA_ gene was not detected in any of the isolates and there was no positive reaction to the PB2 protein, which indicates that none of the isolated strains was methicillin resistant. Only 26.8% of isolated strains did not show the ability to produce biofilm. Special attention should be paid to the health of dairy cows and the supervision of the use of antibiotics in the dairy herd environment because, even in milk from healthy cows, there is a real risk of the occurrence of multi-drug resistant bacteria. antibiotics; biofilms; bulk tank milk; _Staphylococcus_ sp. ; _Staphylococcus aureus_; PCR; raw milk +
Footnote †: journal: Applied  
0000-0001-6600-0001-6600]M.A.S.S. coagulase (coagulase-positive staphylococci--CPS) [7] but also other species belonging to _Staphylococcus_ spp. which do not produce coagulase and were previously considered as saprophvic organisms (coagulase-negative staphylococci--CNS) have become the main pathogens causing mastitis in cattle [8]. These bacteria have numerous and diverse virulence factors that can be divided into two groups: Those that are an integral part of the cell structure and those that are secreted into the environment. Their ability to produce biofilms both in tissues and on abiotic surfaces is considered to be the main cause of virulence. Biofilm enables better protection of staphylococci in the host body against immune mechanisms, and in the case of abiotic surfaces, it makes their cleaning and disinfection more difficult, which is important in maintaining the safety of milk processing. The presence of staphylococci in the production environment [9] and in food of animal origin, including raw milk [10] does not necessarily cause consumer illnesses, but it is a reservoir of bacteria that can be transferred to humans during milk processing and preparation of milk products. Additionally, there is a view that CNS constitute a reservoir of genes determining antibiotic resistance [11; 12]. In recent years, there has been a trend among consumers in Europe to reduce the consumption of animal products. According to a report published as part of the \"Smart-Protein\" project, 51% of Europeans declare that they limit their consumption of meat and other animal products [13]. Despite these declarations, data published by FAO indicate that the production of food of animal origin in the world is still increasing. Therefore, food of animal origin is a significant source of microbiological threats in the environment, including the spread of microbial resistance to antibiotics widely used not only in animal therapy but also in humans. According to the forecast published in the United Nations environmental program report, in the next decade up to 24 million people may be exposed to serious illnesses related to the occurrence of antibiotic resistance of microorganisms, and in 2050 it might be expected up to 10 million deaths resulting from the lack of effective antibiotics [14].