Abstract
Mastitis represents a heavy burden for the dairy sector worldwide with high economic and animal welfare impact. Antibiotic treatment is an important component of mastitis control programs. However, emergence and transfer of antimicrobial-resistant (AMR) bacteria is becoming a growing concern. Therefore, the development of novel agents is required for prevention and treatment of mastitis. Hence, our aim was to assess the antibacterial properties of two essential oils (EOs) obtained from oregano (Origanum vulgare L., Lamiaceae) and mountain savory (Satureja montana L., Lamiaceae) against mastitis-associated bacteria in Serbia. The chemical composition and antioxidant potential of these EOs were also evaluated. The present study was conducted on strains derived from aseptic milk samples collected from Holstein-Friesian cows with clinical or subclinical mastitis, during the morning milking. Clinical mastitis was assessed by clinical examination, while subclinical mastitis was confirmed using somatic cell count in the milk samples. The microdilution method was used to determine the antibacterial activity, while antioxidant potential of the EOs was evaluated in several in vitro assays. The values of minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) were used to quantitatively measure the antibacterial activity of each EO. MIC/MBC ranged from 0.78/6.25 and 0.39/0.78 mg/mL for oregano and mountain savory, respectively. A total of 25 compounds were identified in the oregano EO, while 47 were identified in winter savory EO, among which aromatic oxygenated monoterpenes were the most abundant compounds. The tested EOs have shown promising antimicrobial activity and could be considered as one of the treatment approaches in mastitis-affected cows.
Highlights
As a multifactorial disease, mastitis in dairy cows requires proper herd management to eliminate or minimize its incidence and economic losses due to disease
There is subclinical mastitis followed by changes in milk composition and quantity of milk obtained from the affected quarter, but without visible changes in the mammary gland and/or general condition of the animal
The present study aimed to evaluate in vitro antimicrobial activity of two essential oils (EOs) (Origanum vulgare L., Lamiaceae and Satureja montana L., Lamiaceae) against strains of mastitis-associated pathogens in Serbia, including important representatives of antibiotic
Summary
Mastitis in dairy cows requires proper herd management to eliminate or minimize its incidence and economic losses due to disease. The form of mastitis depends on several factors, such as etiology agent, mammary gland response and changes in general health status. A strong immune response to the microorganisms’ activity in the mammary gland leads to the manifestation of clinical mastitis, which is characterized by changes in the udder and the appearance of milk, with a possibility of altered general condition of the animal. Determination of somatic cell count is a reliable method for diagnosis of subclinical mastitis and is widely recognized as a procedure for control of udder health status changes. It can be used in milk composition measurement. In milk samples from healthy udders it should not exceed 200,000/mL, while in case of mastitis, somatic cells count will be elevated to over one million [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
