Evaluation the Antimicrobial Activity of Essential Oils against Veterinary Pathogens, Multidrug-resistant Bacteria and Dermatophytes

This study aimed to determine the antibiotic and antifungal susceptibility profiles of animal clinical bacterial and fungal isolates and to evaluate the antimicrobial activities of essential oils (EOs) in both the agar disc diffusion method and the broth dilution assay. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) of thyme, mint, and lavender EOs were evaluated. The results of the antibiotic and antifungal susceptibility profiles tests showed differences in the bacterial sensitivities to the studied antibiotics and antimycotics with the emerging of multidrug-resistant bacteria and dermatophytes. Ciprofloxacin was the most effective antibiotic and the tested fungal isolates were much more sensitive to ketoconazole than other antifungals. Thyme essential oil exhibited potent antibacterial activity against every tested strains of bacteria with MICs of less than 9 mu l/ml (0.9%) for the majority of the tested pathogens. The tested EOs effectively inhibited the growth of dermatophytes. Thyme oil presents itself as a promising antibacterial and anti-fungal agent against veterinary pathogens, being a natural product that can represent an interesting antimicrobial in the efforts to combat bacterial and fungal infections in veterinary medicine.