In Vitro Evaluation Of The Antimicrobial Activity Of Thyme (Thymus Zygis) Essential Oil On Staphylococcus Aureus Isolated From Bovine Mastitis

Abstract

The aim of this research was to evaluate in vitro the antimicrobial activity of essential oil of thyme (Thymus zygis) using the Kirby-Bauer technique on Staphylococcus aureus isolated from bovine mastitis. For which, the California Mastitis Test (CMT) technique was used for selective culture media and antimicrobial activity. After CMT, it was determined that the prevalence rate was 48.33%, out of a total of 60 cows tested, resulting in 29 positive animals at diagnosis, of which 20 cows exhibited mastitis caused by Staphylococcus aureus, said pathogen represented 68.96% of the total number of the agents that were able to identify, in addition it was possible to stratify the presentation of said disease where it was exhibited that those animals of the Holstein breed. In the analysis of the antimicrobial activity of the essential oil of thyme, it was possible to observe that the best average was presented by T3 (75%) with a mean of 64.45 mm, followed by T2 (50%) with a mean of 54.95 mm, these versus at T4: Erythromycin 15µg that presented a mean of 19.90 mm. In the analysis of the antimicrobial susceptibility of Erythromycin against Staphylococcus aureus, according to the cut-off points established by CLSI, 95% of the isolates exhibited intermediate resistance and only 5% proved to be sensitive. The minimum inhibitory concentration (MIC) of Essential oil for Staphylococcus aureus, which causes bovine mastitis, was found in a concentration of 7% of thyme essential oil.