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Bulk tank milk from 58 dairy goat and sheep flocks located in southern Spain was examined to determine the prevalence and distribution of Staphylococci . A total of 45 isolates were obtained and characterized to determine the species, antimicrobial resistance profile, and genetic similitude by pulse-field gel electrophoresis (PFGE) using Sma I. Staphylococcus aureus isolates were confirmed by polymerase chain reaction (PCR) analysis of nuc , and resistance to methicillin was determined by PCR analysis of mec A. A total of 10 different staphylococcal species were identified, 22.2% and 77.8% of which were coagulase positive and negative, respectively. Twenty-two (48.89%) isolates were resistant to at least one antimicrobial agent. Higher antimicrobial resistance values were obtained against tetracycline (28.9%) and penicillin (22.2%). Two isolates ( S. aureus and Staphylococcus lentus ) were resistant to cefoxitin; however, none of the 45 isolates harbored mec A. Thirty pulsotypes were detected by PFGE. Interestingly, some isolates of S. aureus , S. lentus , Staphylococcus simulans , and Staphylococcus caprae showed high genetic similarity (>80%). These data suggest that genetically similar staphylococcal isolates circulate among goat and sheep dairy herds, and their different resistance patterns could be influenced by the management systems used.

To determine the distribution of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of essential oils (EOs) of cinnamon (Cinnamomum zeylanicum), clove (Eugenia caryophyllata), oregano (Origanum vulgare), common thyme (Thymus vulgaris), and red thyme (Thymus zygis) against Salmonella enterica, double serial dilutions of each EO were challenged with 85 Salmonella strains belonging to 23 serotypes of animal origin. The results showed the bactericidal character of the EOs tested against S. enterica, highlighting the oregano with MIC 50 and MBC 50 of 3.12 × 10 -4  g/mL, and MIC 90 and MBC 90 of 6.25 × 10 -4  g/mL. When comparing the Salmonella Typhimurium and Salmonella Enteritidis serotypes susceptibility, we observed a significantly higher sensitivity of Typhimurium to clove and Enteritidis to cinnamon. In addition, Typhimurium isolates with significantly higher MIC and MBC values for all the EOs tested were found, suggesting the existence of a possible resistance profile. The results of this study provide relevant data for the potential of EOs as antibacterials, although they highlight the need to continue bacterial sensitivity distribution studies and consider the differences detected for future in vivo studies.