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Introduction: Bovine subclinical mastitis (SCM) caused by Gram-positive bacteria is a major cause of economic loss in the dairy industry, exacerbated in situations where antimicrobial resistance is present. Pure platelet-rich plasma (P-PRP) may be a therapeutic alternative for SCM, when used alone or with antibiotics, such as sodium cloxacillin (SC). This study aimed 1) to evaluate the therapeutic efficacy of allogeneic P-PRP, SC, and their combination (P-PRP+SC) in cows with SCM caused by Staphylococcus aureus and by streptococci (Staphylococcus aureus and S. dysgalactiae); 2) to determine the concentrations of somatic cells (SCC), interleukin 1 beta (IL-1ß), tumor necrosis factor-alpha (TNF-α) and TGF-ß1 in milk samples of the cows. Methods: 130 cows from 4 dairy herds completed the study, of which 40 cows were treated with P-PRP (10 mL), 28 cows with SC (5g), 36 with P-PRP+SC (10mL/5g), and 26 did not receive no treatment (negative control group, NCG). Results: The overall bacteriological cure was observed in 10/40 (25%) cows in the P-PRP group, 9/28 (32.14%) animals in the SC group, 26/36 (72.22%) cows in the P-PRP+SC group, and 10/26 (38.46%) animals in the NCG. SCM caused by S. aureus (82/130, 63.08%), was cured in 6/24 (25%) cows treated with P-PRP, 7/24 (29.2%) cows treated with SC, 8/16 (50%) animals treated with P-PRP+SC, and in 8/18 (44.4%) cows in NCG. For SCM caused by the streptococci (48/130, 36.91%), the cure was achieved in 4/12 (33.3%) cows treated with P-PRP, 2/4 (50%) cows treated with SC, 18/20 (90%) cows treated with P-PRP+SC, and in 2/8 (25%) cows of the NCG. SCC was significantly (p < 0.001) affected by the treatment, herd, cure, bacteria group, and number of calvings factors. IL-1ß milk concentrations were significantly (p < 0.001) influenced by treatment and farm factors, and the interaction between these factors. TNF-α milk concentrations were significantly (p < 0.001) influenced by time factor. TGF-ß1 milk concentrations were significantly affected by the time and cure factors. Conclusion: The combination of P-PRP and SC showed the best therapeutic response (90%) against bovine SCM caused by streptococci. However, none of the treatments showed an effective therapeutic response against S. aureus.

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In India, where dairy production leads globally, infrared thermography (IRT) and short milking tube thermography specifically are vital for managing mastitis. Therefore, the present study focuses on thermal imaging of the udder and short milking tube (SMT) of the milking machine during the peak milking process of Sahiwal cows and Murrah buffaloes during winter, summer, rainy and autumn seasons to identify sub-clinical (SCM) and clinical mastitis (CM) cases using the Darvi DTL007 camera. The udder health was assessed using the California Mastitis Test, Somatic Cell Count (SCC) and IRT throughout the year. Log10SCC and thermogram analysis revealed a difference (p < 0.01) between healthy, SCM, and CM cases during different seasons in both breeds. Further results showed an increase (p < 0.01) in SMT thermograms of SCM and CM cases compared to healthy quarters in Sahiwal cows during winter, summer, rainy, and autumn were 4.26 and 7.51, 2.37 and 4.47, 2.20 and 3.64, 2.90 and 4.94 ºC, respectively and for Murrah buffaloes were 3.56 and 5.55, 2.70 and 3.81, 1.72 and 3.10, 3.14 and 4.42ºC, respectively. The highest degree of increase in milking udder skin surface temperature and SMT of SCM and CM cases compared to healthy quarters was observed during the winter and the least during the rainy season. Thus, regardless of the seasons examined in this study, SMT thermograms effectively assessed SCM and CM.

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Mastitis is a significant factor that decreases milk production in cows of different breeds in Kazakhstan. The objective of this study was to determine the genetic makeup of Holstein cows by analysing specific gene loci (SELL, MX1, CXCR1+291C>T and CXCR1+1093C>T) that are linked to resistance against mastitis. The goal was to identify cows with favourable genotypes that are less prone to udder diseases. At the SELL gene locus c.567T>C, all three genetic variants were identified in the control population with the respective frequencies: TT (0.20), CT (0.44), and CC (0.36). Genetic variation was also detected at the MX1 gene c.567T>C, CXCR1 c.+291C>T and CXCR1+1093C>T loci. Deviation from the expected Hardy-Weinberg equilibrium was observed for two gene loci, MX1 g.143182088 and CXCR1+1093C>T, with increased chi-square values of 10.6261 and 9.7137, respectively. The analysis of subclinical mastitis incidence indicates that cows carrying the heterozygous CT genotype at the L-selectin gene locus exhibit greater resistance to the disease. Animals carrying the CCCCCT genotype at the MX1 c.567T>C, CXCR1 c.+291C>T and CXCR1+1093C>T gene loci were discovered to have a significant likelihood of developing subclinical mastitis. This suggests that these genes could serve as potential indicators of susceptibility to the condition. The practical significance of this study lies in determining the frequency of genotypes linked to mammary gland morbidity in Holstein breeding farms in Kazakhstan.

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Mastitis in cows is one of the most important diseases that give rise to economic losses in dairy farms. Increasing antimicrobial resistance in Staphylococcus aureus, one of the most common causes of mastitis, is a significant health problem. Due to the problems encountered in treating infections caused by resistant strains, developing alternative treatment methods, such as Nanomaterial systems and natural agents, are important. The essential oil of Melaleuca alternifolia is used as an antibacterial and the primary active component is terpinen-4-ol. This study aimed to investigate the antibacterial and anti-biofilm activity of terpinen-4-ol and terpinen-4-ol loaded polydopamine (T-PDA) nanoparticles against S. aureus isolates, which were resistant to at least one group of antibiotics isolated from milk samples of subclinical mastitis cows. The S. aureus strains were identified by biochemical tests and verified with the API Staph kit. The antibiotic susceptibility of the isolates was determined by the disc diffusion method. The broth microdilution method determined the antimicrobial activities of the terpinen-4-ol and T-PDA nanoparticles, and anti-biofilm activities were assessed using the modified crystal violet method. All of the isolates were resistant to benzylpenicillin and susceptible to trimethoprim/sulfamethoxazole. Multi-antibiotic resistance was detected in the 11 S. aureus isolates used in this study. For the terpinen-4-ol and T-PDA nanoparticles, MIC values were determined in the range of 0.125-0.5% (µL/mL) and 0.125-0.25% (µL/mL), respectively. None of the isolates formed biofilms. As a result, it was found that the antibacterial efficacy of the T- PDA nanoparticles was higher against nine of the S. aureus isolates than against the terpinen-4-ol.

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Subclinical mastitis is an asymptomatic inflammatory condition that can be difficult to define and diagnose. In the dairy industry, subclinical mastitis is diagnosed by milk somatic cell counts (SCCs) of ≥250,000 cells mL-1. In this pilot study, we assessed the efficacy of this index to identify human subclinical mastitis by comparing SCC levels with the inflammatory response [interleukin-8 (IL-8) levels] in 37 samples from asymptomatic and 10 clinical mastitis (CM) lactating women. The milk microbiota was determined by 16S rRNA gene sequencing. The SCC of CM samples ranged from 310,000 to 6,600,000 cells mL-1. However, 14 of 37 (37.8%) asymptomatic samples had high SCC (250,000-460,000 cells mL-1), indicating subclinical mastitis. SCC levels significantly (P < 0.001) and positively correlated with milk IL-8 levels reflecting the escalating inflammatory response across subclinical and clinical mastitis samples. Samples with an SCC of ≥250,000 cells mL-1 showed significant increases in IL-8 responses when compared with milk samples from healthy women. The milk microbiome of CM samples was dominated by streptococcal and staphylococcal species (89.9% combined median relative abundance). In contrast, the combined median streptococcal/staphylococcal relative levels were 75.4% and 66.3% in milks from asymptomatic (subclinical mastitis) and healthy groups, respectively. The Streptococcus genus was increased in samples with an SCC of ≥250,000, although this should be interpreted with caution. Thus, the index of ≥250,000 somatic cells mL-1 could be a reliable indicator of subclinical mastitis in humans and should aid future studies investigating the impact of subclinical mastitis on maternal health, breastfeeding behaviors, infant health, and development. IMPORTANCE: This pilot study suggests that SCC at a level of (greater than or equal to) 250,000 cells mL-1, as used in the dairy industry, is a suitable index to identify asymptomatic subclinical mastitis in lactating women since it reflects a significant increase in the inflammatory response compared to milk samples from healthy women. Using this index should aid studies into the short- and long-term consequences of subclinical mastitis for mother and infant.

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BACKGROUND: Acinetobacter lwoffii (A. lwoffii) is a Gram-negative bacteria common in the environment, and it is the normal flora in human respiratory and digestive tracts. The bacteria is a zoonotic and opportunistic pathogen that causes various infections, including nosocomial infections. The aim of this study was to identify A. lwoffii strains isolated from bovine milk with subclinical mastitis in China and get a better understanding of its antimicrobial susceptibility and resistance profile. This is the first study to analyze the drug resistance spectrum and corresponding mechanisms of A. lwoffii isolated in raw milk. RESULTS: Four A. lwoffii strains were isolated by PCR method. Genetic evolution analysis using the neighbor-joining method showed that the four strains had a high homology with Acinetobacter lwoffii. The strains were resistant to several antibiotics and carried 17 drug-resistance genes across them. Specifically, among 23 antibiotics, the strains were completely susceptible to 6 antibiotics, including doxycycline, erythromycin, polymyxin, clindamycin, imipenem, and meropenem. In addition, the strains showed variable resistance patterns. A total of 17 resistance genes, including plasmid-mediated resistance genes, were detected across the four strains. These genes mediated resistance to 5 classes of antimicrobials, including beta-lactam, aminoglycosides, fluoroquinolones, tetracycline, sulfonamides, and chloramphenicol. CONCLUSION: These findings indicated that multi-drug resistant Acinetobacter lwoffii strains exist in raw milk of bovine with subclinical mastitis. Acinetobacter lwoffii are widespread in natural environmental samples, including water, soil, bathtub, soap box, skin, pharynx, conjunctiva, saliva, gastrointestinal tract, and vaginal secretions. The strains carry resistance genes in mobile genetic elements to enhance the spread of these genes. Therefore, more attention should be paid to epidemiological surveillance and drug resistant A. lwoffii.

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Background: Beta-glucan (ß-glucan) is a polysaccharide containing ß-glycosidic bonds that is an important structure part of different yeast cells. Aim: The purpose of the study is to characterize ß-glucan obtained from Candida albicans (C. albicans) isolated from caprine mastitis. Methods: The ß-glucan was extracted by using utilizing an Alkaline-acidic extraction technique. The dry weight of extracted ß-glucan was 7.47/150 g with 4.98%. Results: The findings demonstrated that the extracted ß-glucan had similarity in the primary peak 5.78 of liquid samples using the method of high-performance liquid chromatography when compared to the standard form of ß-glucan. However, scanning electron microscopy studies revealed that the standard of ß-glucan was distinct in morphology but similar to ß-glucan isolated from C. albicans in terms of particle sizes in the range of 1.60-2.65 m and the lack of cell wall traces. The findings of an investigation using energy-dispersive X-ray fluorescence spectroscopy (EDS/EDX) of extracted and standard ß-glucan, showed the principal elements discovered were carbon (C), oxygen (O), and nitrogen (N). Aluminum (Al), silicon (Si), nickel (Ni), and gold (Au) were also present, but in less amounts. Conclusion: The extracted ß-glucan displayed a high degree of similarity and purity to the standard ß-glucan, according to the findings of Fourier transform infrared spectroscopy (FT-IR) research.

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Subclinical mastitis is a common and economically significant disease that affects dairy sheep production. Thermal imaging presents a promising avenue for non-invasive detection, but existing methodologies often rely on simplistic temperature differentials, potentially leading to inaccurate assessments. This study proposes an advanced algorithmic approach integrating thermal imaging processing with statistical texture analysis and t-distributed stochastic neighbor embedding (t-SNE). Our method achieves a high classification accuracy of 84% using the support vector machines (SVM) algorithm. Furthermore, we introduce another commonly employed evaluation metric, correlating thermal images with commercial California mastitis test (CMT) results after establishing threshold conditions on statistical features, yielding a sensitivity (the true positive rate) of 80% and a specificity (the true negative rate) of 92.5%. The evaluation metrics underscore the efficacy of our approach in detecting subclinical mastitis in dairy sheep, offering a robust tool for improved management practices.

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Mastitis is a global production disease that needs an intelligent solution to tackle effectively. Infrared Thermography (IRT) is a non-invasive technology that could be incorporated into routine day-to-day farm activities to monitor the health status of the animals. In this study, the udder health status was routinely monitored for 30 days among 41 Murrah buffaloes via IRT and the California Mastitis Test (CMT). Further, somatic cell count (SCC), microbial identification, and milk quality parameters were also estimated for representative samples. The thermal imaging data obtained was tabulated and back propagated from the 0th day to the -10th day and front propagated from the 0th day to +10th day for all the udder quarters. Results revealed that on the 0th day, the mean of udder skin surface temperature (USST) and teat skin surface temperature (TSST) showed a difference (p < 0.05) in the sub-clinical mastitis (SCM) and clinical mastitis (CM) affected quarters to the healthy quarters, and their degree of difference was the highest. The indication of infection was signaled during the -9th to -5th day to the 0th day in SCM and CM cases. There was a steep increment in the temperature from -2nd and -1st day to the 0th day of infection. Sometimes, some quarters show an increment in temperature due to mastitis during morning hours but recover by evening milking due to the animal's innate immune system. Thus, the initiation period in which the udder gets assaulted is crucial in the early assessment of SCM by monitoring temperature change using IRT.

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Mastitis represents the biggest threat to the health and productivity of dairy cows, leading to substantial economic losses in milk production. It manifests in two forms: clinical mastitis, easily diagnosed by visible symptoms, and subclinical mastitis (SCM), which lacks overt clinical signs. SCM's elusive nature often results in it going undetected, thus facilitating the spread of the disease-causing agent due to lack of treatment. Finding a reliable biomarker for early SCM would reduce the possibility of mastitis spreading in the herd, reduce the need for antibiotic use and ultimately reduce milk losses for producers. Utilizing state-of-the-art proteomics techniques, 138 milk samples from dairy cows in continental Croatia underwent analysis. These samples were categorized into four groups based on the Zagreb Mastitis Test (ZMT) and microbiological analysis: lowSCC- (n = 20), lowSCC + (n = 20), medSCC + (n = 79), and highSCC + (n = 19). A total of 386 proteins were identified and quantified, with 76 proteins showing significant differential abundances among the groups. Many of these proteins are linked to the innate immune system, as well as neutrophil and platelet degranulation processes. Through fold changes observed between groups, 15 proteins exhibiting biomarker characteristics for subclinical mastitis (SCM) were identified. Among these, five proteins-cathelicidins (-1, -4, and -7), lactoferrin, and haptoglobin-showed particular promise.

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Mastitis is considered one of the most widespread infectious disease of cattle and buffaloes, affecting dairy herds. The current study aimed to characterize the Staphylococcus aureus isolates recovered from subclinical mastitis animals in Pothohar region of the country. A total of 278 milk samples from 17 different dairy farms around two districts of the Pothohar region, Islamabad and Rawalpindi, were collected and screened for sub clinical mastitis using California Mastitis Test. Positive milk samples were processed for isolation of Staphylococcus aureus using mannitol salt agar. The recovered isolates were analyzed for their antimicrobial susceptibility and virulence genes using disc diffusion and PCR respectively. 62.2% samples were positive for subclinical mastitis and in total 70 Staphylococcus aureus isolates were recovered. 21% of these isolates were determined to be methicillin resistant, carrying the mecA gene. S. aureus isolates recovered during the study were resistant to all first line therapeutic antibiotics and in total 52% isolates were multidrug resistant. SCCmec typing revealed MRSA SCCmec types IV and V, indicating potential community-acquired MRSA (CA-MRSA) transmission. Virulence profiling revealed high prevalence of key genes associated with adhesion, toxin production, and immune evasion, such as hla, hlb, clfA, clfB and cap5. Furthermore, the Panton-Valentine leukocidin (PVL) toxin, that is often associated with recurrent skin and soft tissue infections, was present in 5.7% of isolates. In conclusion, the increased prevalence of MRSA in bovine mastitis is highlighted by this study, which also reveals a variety of virulence factors in S. aureus and emphasizes the significance of appropriate antibiotic therapy in combating this economically burdensome disease.

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The aim of the study was to investigate the effect of the immunostimulant Mycobacterium Cell Wall Fraction (MCWF) on the treatment of S. aureus SCM by intravenous application. The study included 45 HF dairy cows in 2nd and 3rd month after parturition divided into three groups (n = 15 per group): the MC + group - cows with S. aureus SCM treated with MCWF; the MC- group - cows with S. aureus SCM, with no treatment; and the C group - the control group of healthy cow with no treatment. Samples were collected 0th (I sample), 7th (II), and 14th day (III) from the day of SCM diagnosis and on day 21st (IV). A greater influx of leukocytes was confirmed into milk after 7 days after MCWF treatment in MC + group, which was followed by increase of WBC and LYM in blood. These results support the hypothesis of effective action of MCWF, and in quarters with lower-grade infection, bacteriological cure was achieved. The MC- group had a statistically higher concentration of TBARS and CAT activity in milk, while MC + group had lower blood serum LDH activity, which indicates a positive effect of the MCWF application and a lower exposure of the tissue to lipide peroxidation and inflammation caused by S. aureus. The application of MCWF would give new possibilities in the prevention and therapy of mammary gland diseases without fear of the presence of residues and the emergence of bacterial resistance. In future studies, the effects of local and systemic application of MCWF in the treatment of S. aureus SCM should be compared.

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Current research aims to generate an alternative model to classical methods in the determination of subclinical mastitis at 4 levels (healthy, suspicious, subclinical, and clinical). For this purpose, multilayer perceptron (MLP) artificial neural networks (ANN) was developed as test model. 5 variables from the physical properties of milk somatic cell count (SCC), electrical conductivity (EC), pH, density, and temperature at fore milking (TFM) were included in the model in the classification of mastitis. Model performance was validated on test data (%25) and compared with the multinomial logistic regression (MNLR). MLP model has shown a satisfactory performance with an accuracy of 95.14% and - 141 of AIC score better than the control model (MNLR) of 80.27% and - 133 AIC despite using higher number of parameters (104). Since the main problem is to diagnose subclinical mastitis, which does not cause any visible symptoms, it was important to distinguish between absolute subclinical (suspicious excluded positives) and absolute healthy (suspicious included positives) ones. Therefore, optimum cut-off threshold was evaluated for these two different scenarios with only variable SCC the gold standard indicator of subclinical mastitis and results were compared in the interpretation of model performance. The results show that the 5-variable MLP model exhibits a high sensitivity of 93.22% (AUC = 0.95 for healthy ones) at low cutoff thresholds as well. New studies should provide a better understanding by evaluating economics, sustainability, animal welfare and health aspects together to determine the optimal threshold value.

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This study investigates the relationships between subclinical mastitis and milk quality with selected microRNAs in cow milk. California Mastitis Test (CMT)-positive (n = 20) and negative (n = 20) samples were compared (Experiment I). Additionally, samples with CMT-positive but microbiological-negative, as well as positive for only Staphylococcus subspecies (Staph spp.) and only Streptococcus subspecies (Strep spp.) were examined (Experiment II). Four groups were formed in Experiment II: Group I (CMT and microbiological-negative) (n = 20), Group II (CMT-positive but microbiological-negative) (n = 10), Group III (Staph spp.) (n = 5), Group IV (Strep spp.) (n = 5). While electrical conductivity, somatic cell count (SCC), malondialdehyde (MDA) increased, miR-27a-3p and miR-223 upregulated and miR-125b downregulated in the CMT-positive group in Experiment I. SCC and MDA were higher in CMT-positive groups. miR-27a-3p and miR-223 upregulated in Groups III and IV. While miR-155 is upregulated, miR-125b downregulated in Group IV. Milk fat is positively correlated with miR-148a and miR-223. As miR-27a-3p positively correlated with SCC and MDA, miR-125b negatively correlated with electrical conductivity and SCC. miR-148a and MDA were positively correlated. miR-155 was correlated with fat-free dry matter, protein, lactose, and freezing point. miR-223 was positively correlated with SCC and miR-148a. Results particularly highlight miR-27a-3p and miR-223 as potential biomarkers in subclinical mastitis, especially those caused by Staph spp. and Strep spp., while miR-148a, miR-155, and miR-223 stand out in determining milk quality.

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Mastitis is a common mammary gland disease of dairy cattle caused by a wide range of organisms including bacteria, fungi and algae. Mastitis contributes to economic losses of dairy farms due to reduced yield and poor quality of milk. Since the correct identification of pathogens responsible for the development of mastitis is crucial to the success of treatment, it is necessary to develop a quick and accurate test to distinguish the main pathogens causing this disease. In this paper, we describe the development of a test based on the multiplex polymerase chain reaction (PCR) method allowing for the identification of Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis and Staphylococcus aureus. When creating our test, we relied on the results from new generation sequencing (NGS) for accurate determination of species affiliation. The multiplex PCR test was verified on 100 strains including veterinary samples, ATCC and Polish Collection of Microorganisms (PCM) reference strains. The obtained results indicate that this test is accurate and displays high specificity. It may serve as a valuable molecular tool for the detection of major mastitis pathogens.

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The objective of this study was the presentation of quantitative characteristics regarding the scientific content and bibliometric details of the relevant publications. In total, 156 papers were considered. Most papers presented original studies (n = 135), and fewer were reviews (n = 21). Most original articles (n = 101) referred to work involving cattle. Most original articles described work related to the diagnosis (n = 72) or pathogenesis (n = 62) of mastitis. Most original articles included field work (n = 75), whilst fewer included experimental (n = 31) or laboratory (n = 30) work. The tissue assessed most frequently in the studies was milk (n = 59). Milk was assessed more frequently in studies on the diagnosis (61.1% of relevant studies) or pathogenesis (30.6%) of the infection, but mammary tissue was assessed more frequently in studies on the treatment (31.0%). In total, 47 pathogens were included in the studies described; most were Gram-positive bacteria (n = 34). The three bacteria most frequently included in the studies were Staphylococcus aureus (n = 55 articles), Escherichia coli (n = 31) and Streptococcus uberis (n = 19). The proteomics technology employed more often in the respective studies was liquid chromatography-tandem mass spectrometry (LC-MS/MS), either on its own (n = 56) or in combination with other technologies (n = 40). The median year of publication of articles involving bioinformatics or LC-MS/MS and bioinformatics was the most recent: 2022. The 156 papers were published in 78 different journals, most frequently in the Journal of Proteomics (n = 16 papers) and the Journal of Dairy Science (n = 12). The median number of cited references in the papers was 48. In the papers, there were 1143 co-authors (mean: 7.3 ± 0.3 co-authors per paper, median: 7, min.-max.: 1-19) and 742 individual authors. Among them, 15 authors had published at least seven papers (max.: 10). Further, there were 218 individual authors who were the first or last authors in the papers. Most papers were submitted for open access (n = 79). The median number of citations received by the 156 papers was 12 (min.-max.: 0-339), and the median yearly number of citations was 2.0 (min.-max.: 0.0-29.5). The h-index of the papers was 33, and the m-index was 2. The increased number of cited references in papers and international collaboration in the respective study were the variables associated with most citations to published papers. This is the first ever scientometrics evaluation of proteomics studies, the results of which highlighted the characteristics of published papers on mastitis and proteomics. The use of proteomics in mastitis research has focused on the elucidation of pathogenesis and diagnosis of the infection; LC-MS/MS has been established as the most frequently used proteomics technology, although the use of bioinformatics has also emerged recently as a useful tool.

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Staphylococcus species are the primary cause of mastitis in dairy cows across the world. Staphylococcus aureus has recently become a pathogen that is zoonotic and multidrug resistant. This study aimed to sequence whole genomes of 38 S. aureus isolates from 55 subclinical mastitis dairy cows of 7 small-scale farmers in the Free State Province, South Africa and document and their antimicrobial and virulence genes. The 38 isolates were grouped by the in silico multi-locus sequencing types (MLST) into seven sequence types (STs), that is (ST 97, 352, 152, 243) and three new STs (ST8495, ST8500, and ST8501). Thirty-three S. aureus isolates were divided into 7 core single-nucleotide polymorphism (SNP) clusters. Among the 9 distinct spa-types that were detected, Spa-types t2883 accounted for the majority of isolates at 12 (31.57%), followed by t416 with 11 (28.94%) and t2844 with 5 (13.15%). The data also revealed the identification of four (4) plasmids, with Rep_N (rep20) accounting for the majority of isolates with 17 (44.73%), followed by Inc18 (repUS5) with 2 (5.26%). These isolates included 11 distinct antimicrobial resistance genes and 23 genes linked to bacterial virulence. Surprisingly, no methicillin resistance associated genes were detected in these isolates. Genome data of the current study will contribute to understanding epidemiology S. aureus genotypes and ultimately aid in developing treatment and control plans to stop the spread of mastitis in the Free State province and South Africa as a whole.

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This field trial was conducted to evaluate two antibiotics at a close-up period in curing the existing IMI and to prevent new clinical and subclinical Intramammary infection (IMI). Two hundred and twelve Holstein cows were assigned to one of three treatment groups: TYLO, MARB and CONT. Cows in TYLO group received 10 mg/kg Tylosin for three days at the close-up period (21 days before calving), cows in MARB group received single SC injection of 8 mg/kg SC marbofloxacin at the close-up period and cows in CONT group remained untreated. Milk samples were collected for somatic cell count, microbial culture and Total oxidant/antioxidant capacity before drying-off, and 3 and 7days post calving. Antimicrobial susceptibility test and RAPT-PCR were performed on S.aureus isolates. No significant differences were detected in total cure rate within the groups, but S. aureus cure rates in TYLO and MARB were significantly higher than in CONT (74 and 73.5 % Vs 58.1 %). No significant differences in total new IMI were observed. Furthermore, the rate of new S. aureus IMI was higher in both treatment groups than in CONT group. Clinical mastitis rate in TYLO (3.8 %) and MARB (5.8 %) was significantly lower than CONT (11.3 %). Paired S. aureus isolates from dry-off and post-calving have been clustered into 9 different RAPD types (A-I). 8 paired strains collected at dry-off were identical to those at post-calving,and 35 strains had more than 60 % dissimilarity. Administration of Tylosin or Marbofloxacin is not useful in all cases;however, they have the potential to reduce the incidence of post-calving clinical mastitis and improve S.aureus cure rate if used selectively.

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Mycoplasma bovis has recently been identified increasingly in dairy cows causing huge economic losses to the dairy industry. M. bovis is a causative agent for mastitis, pneumonia, endometritis, endocarditis, arthritis, otitis media, and many other clinical symptoms in cattle. However, some infected cows are asymptomatic or may not shed the pathogen for weeks to years. This characteristic of M. bovis, along with the lack of adequate testing and identification methods in many parts of the world until recently, has allowed the M. bovis to be largely undetected despite its increased prevalence in dairy farms. Due to growing levels of antimicrobial resistance among wild-type M. bovis isolates and lack of cell walls in mycoplasmas that enable them to be intrinsically resistant to beta-lactam antibiotics that are widely used in dairy farms, there is no effective treatment for M. bovis mastitis. Similarly, there is no commercially available effective vaccine for M. bovis mastitis. The major constraint to developing effective intervention tools is limited knowledge of the virulence factors and mechanisms of the pathogenesis of M. bovis mastitis. There is lack of quick and reliable diagnostic methods with high specificity and sensitivity for M. bovis. This review is a summary of the current state of knowledge of the virulence factors, pathogenesis, clinical manifestations, diagnosis, and control of M. bovis mastitis in dairy cows.

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The present study focused on Sahiwal cows, a prominent milch breed in tropical India, to correlate udder temperature with physiological markers of stress and inflammation during subclinical mastitis (SCM). The primary goal was to assess the potential of udder infrared thermography for the early detection of SCM under the semi-intensive production. Cows were categorized based on milk somatic cell counts (SCC), with healthy (H) cows having SCC <2 × 105 cells/mL and no history of mastitis, and cows with subclinical mastitis (SCM) and initial stages of clinical mastitis (CM) having quarter milk SCC of 2-5 × 105 and >5 × 105 cells/mL, respectively. Firstly, udder thermograms were analysed for udder skin surface temperature (USST), teat skin surface temperature (TSST), and teat apex temperature (TAT) using Fluke software to determine the optimal site for temperature measurement during intramammary infection. Secondly, milk samples were collected for automatic estimation of compositional changes, electrical conductivity, and pH. Thirdly, milk whey was separated for quantifying stress and inflammatory indicators, including cortisol, prolactin, and acute-phase proteins (APPs): milk amyloid A and milk haptoglobin using bovine-specific ELISA kits. Significant increases (p < 0.01) in USST, TSST, TAT, cortisol, and APPs were observed in SCM and CM compared to healthy cows, while prolactin levels decreased (p < 0.01). The correlation matrix revealed strong positive correlations of SCC with USST (r = 0.84, p < 0.01). In ROC analysis, USST demonstrated cut-off values of 37.74 and 39.58 °C, with accuracy (p < 0.05) of 98% for SCM and 95% for CM, surpassing both TAT and TSST. Therefore, the combination of these non-invasive methods increases the reliability and accuracy of infrared thermography for early detection of SCM, providing valuable insights for the development of a protocol for routine screening and udder health monitoring in indigenous dairy cows.

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