Staphylococcus aureus and coagulase-negative staphylococci are among the major causes of mastitis in sheep. The main goal of this research was to determine the in vitro antibacterial activity of several essential oils (EOs, n 30), then five of them were chosen and tested alone and in blends against staphylococci isolates. Five bacteria were isolated from episodes of ovine mastitis (two S. aureus and three S. xylosus). Biochemical and molecular methods were employed to identify the isolates and disk diffusion method was performed to determine their antimicrobial-resistance profile. The relative percentage of the main constituents in the tested essential oils and their blends was detected by GC-EIMS analysis. Antibacterial and bactericidal effectiveness of essential oils and blends were evaluated through minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). All of them showed sensitivity to the used antimicrobials. The EOs with the highest antibacterial activity were those belonging to the Lamiaceae family characterized by high concentrations of thymol, carvacrol and its precursor p-cymene, together with cinnamon EO, rich in cinnamaldehyde. In terms of both MIC and MBC values, the blend composed by Thymus capitatus EO 40%, Cinnamomum zeylanicum EO 20%, Thymus serpyllum EO 20% and Satureja montana EO 20% was found to be the most effective against all the isolates. Some essential oils appear to represent, at least in vitro, a valid tool against ovine mastitis pathogens. Some blends showed a remarkable effectiveness than the single oils, highlighting a synergistic effect in relation to the phytocomplex.

金黄色葡萄球菌和凝固酶阴性葡萄球菌是绵羊乳腺炎的主要原因。这项研究的主要目标是确定几种精油（EOs，n 30）的体外抗菌活性，然后选择其中的五种并单独和混合使用以对抗葡萄球菌分离株进行测试。从绵羊乳腺炎发作中分离出五种细菌（两个金黄色葡萄球菌和三个木糖葡萄球菌）。采用生化和分子方法鉴定分离物，并采用圆盘扩散法确定其抗药性。通过GC-EIMS分析检测了被测精油及其混合物中主要成分的相对百分比。通过最小抑菌浓度（MIC）和最小抑菌浓度（MBC）评估了香精油及其混合物的抗菌和杀菌效果。它们都显示出对所用抗微生物剂的敏感性。具有最高抗菌活性的EOs是属于唇形科的那些，其特征在于百里酚，香芹酚及其前体p的浓度高。-Cymene，与肉桂EO一起，富含肉桂醛。在这两种MIC和MBC值，通过组成的共混物而言胸腺capitatus EO 40％，锡兰肉桂EO 20％，百里香EO 20％和香薄荷属蒙大拿EO 20％被认为是最有效的对抗所有的分离物。一些精油似乎至少在体外代表了一种有效的抗绵羊乳腺炎病原体的工具。一些混合物显示出比单一油更显着的功效，突出了与植物复合物的协同作用。