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.

Due to the emergence of antibiotic-resistant bacteria, the risk it represents to public health, and the possible consequences for animal health and welfare, there is an increasing focus on reducing antimicrobial usage (AMU) in animal husbandry. Therefore, a great interest in developing alternatives to AMU in livestock production is present worldwide. Recently, essential oils (EOs) have gained great attention as promising possibilities for the replacement of antibiotics. The current study aimed to test the potential of using a novel EO-based pharmaceutical formulation (Phyto-Bomat) in bovine mastitis treatment. The antibacterial activity was performed using the microdilution technique. Lactating dairy cows were treated with 15 mL of Phyto-Bomat in the inflamed quarter for 5 consecutive days in order to analyze blood and milk samples for thymol and carvacrol residues using gas chromatography and mass spectrometry (GC–MS). Antimicrobial activity expressed as the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) indicates that this formulation has the highest activity against Gram-positive strains. The dominant compounds in Phyto-Bomat were thymol and carvacrol, at 12.58 ± 1.23 mg/mL and 23.11 ± 2.31 mg/mL, respectively. The quantification of these two compounds in evaluated biological samples showed that 24 h after administration the concentration of thymol and carvacrol in milk samples was at the same level as before application. On the other hand, thymol and carvacrol were detectable in plasma samples even after 24 h post-treatment, with values ranging from 0.15–0.38 and 0.21–0.66 µg/mL, respectively. The tested formulation showed encouraging results of antibacterial activity against bovine mastitis pathogens, as well as the withdrawal period of dominant compounds, which implies that further testing regarding the bacteriological and clinical cure rates in clinical settings is needed.

Control of udder health is an essential element in the process of safe milk production. Thus through the mastitis control program dairy farms regularly conduct measures of detection and prevention of udder diseases. Subclinical mastitis is an important disease of dairy cows causing economic losses and physical and chemical changes in milk. The aim of this research was to evaluate the usefulness of the California and the Draminski mastitis test to detect the subclinical mastitis in dairy cows. The efficacy of indirect mastitis tests for diagnosis of the subclinical mastitis was determined by comparing results of mastitis tests with bacteriological findings. The experiment was conducted on two dairy farms (farm A and farm B) Holstein -Friesian breed. A total of 245 quarter milk samples were examined, 95 quarter milk samples with the California mastitis test from farm A and 150 quarter milk samples with the Draminski mastitis test from farm B. A quarter milk samples for bacteriological analysis were taken aseptically during the morning milking in sterile test tubes. On farm A, bacteria growth has not been detected in 46.32% (44/95) quarter milk samples, while on farm B negative bacteriological findings have been found in 50.67% samples (76/150). In present study, sensitivity of the California mastitis test (78.57%) is higher than sensitivity of the Draminski mastitis test (74.32%). The specificity of the California mastitis test and the Draminski mastitis test is 82.05% and 30.26%, respectively. Efficacy of the California mastitis test in detection of the subclinical mastitis in dairy cows is better than that of the Draminski mastitis test, since accuracy of the California mastitis test has been higher.

Increasing pressure on animal and human health as well as food security, due to antimicrobial resistance, is leading to increased demand for natural-product-derived antibiotics worldwide. Considering the importance of bovine mastitis as well as the huge challenge posed by mastitis therapy in cattle production, the main goal of this research was to evaluate the effectiveness of the essential oil-based pharmaceutical (Phyto-Bomat), as an alternative to the existing treatment with antibiotics. The therapeutic response of the cows was monitored using clinical and bacteriological cure of the proposed formulation. Among 550 dairy cows, 75 were diagnosed with a clinical or subclinical form of mastitis and divided into three experimental groups: treated with antibiotic; Phyto-Bomat; antibiotic and Phyto-Bomat. Indicators of bacteriological cure were somatic cell count (SCC), total bacterial count, and causative agent isolation, while the clinical cure was accessed by observing physical udder conditions. All mentioned indicators were assessed before and after the treatment (1st and 7th day post-treatment), with all of the three therapeutic protocols. After Phyto-Bomat treatment, no visible signs of irritation were noticed, while no significant effect in reducing SCC and total bacterial count was observed. Phyto-Bomat has shown promising results in the treatment of mastitis, without the risk of udder irritation, alone or in combination with antibiotics as part of a mastitis control program during lactation.

Mastitis is one of the most important health problems in dairy cows. In addition to thehealth aspect and the apparent impact on animal welfare, mastitis is the largest financial cost in dairyfarms due to treatment costs and rejected milk because of the withdrawal period, as well aspermanently reduced milk production or complete lactation interruption in heavy form of mastitis.The procedure and the outcome of the treatment depend on the form of udder inflammation, degreeof tissue alteration, timing of treatment initiation and the application of adequate preparations or theappropriate procedure. The outcome of therapy can be full restitution of parenchyma and its functionor deterioration of the glandular parenchyma and filling with connective tissue. Nowadays, inconditions of intensive milk production, mastitis therapy is only part of a mastitis control programthat puts mastitis prevention at the forefront. In case of clinical mastitis, it is necessary to applytherapy during lactation.