Skip to content
naulon

No retraction, correction or concern found when last checked on Oct 27, 2026.

Escherichia coli Mastitis in Dairy Cattle: Etiology, Diagnosis, and Treatment Challenges

Débora Brito Goulart, Melha Mellata

Frontiers in Microbiology · 2022 · Review · CC BY

doi:10.3389/fmicb.2022.928346

Abstract

Bovine mastitis is an inflammation of the udder tissue parenchyma that causes pathological changes in the glandular tissue and abnormalities in milk leading to significant economic losses to the dairy industry across the world. Mammary pathogenic Escherichia (E.) coli (MPEC) is one of the main etiologic agents of acute clinical mastitis in dairy cattle. MPEC strains have virulence attributes to resist the host innate defenses and thrive in the mammary gland environment. The association between specific virulence factors of MPEC with the severity of mastitis in cattle is not fully understood. Furthermore, the indiscriminate use of antibiotics to treat mastitis has resulted in antimicrobial resistance to all major antibiotic classes in MPEC. A thorough understanding of MPEC’s pathogenesis and antimicrobial susceptibility pattern is required to develop better interventions to reduce mastitis incidence and prevalence in cattle and the environment. This review compiles important information on mastitis caused by MPEC (e.g., types of mastitis, host immune response, diagnosis, treatment, and control of the disease) as well as the current knowledge on MPEC virulence factors, antimicrobial resistance, and the dilemma of MPEC as a new pathotype. The information provided in this review is critical to identifying gaps in knowledge that will guide future studies to better design diagnostic, prevent, and develop therapeutic interventions for this significant dairy disease.

Full text

From PubMed Central, U.S. National Library of Medicine, as current on Oct 27, 2026. Paragraph numbers are ours, so an answer can point at one.

Introduction

Bovine mastitis is an inflammation of the udder tissue parenchyma that may result in physical, chemical, and bacteriological changes in milk, and pathological alterations in the glandular tissue. Although mastitis can be caused by multiple events, e.g., traumatic, physiological, allergic, etc., infectious events are the most prevalent, as more than 140 species of microorganisms are involved in bovine mastitis. The disease results in significant financial losses owing to diagnostic tests, veterinary services, wasted milk and labor, and indirect expenses such as low reproduction rates and premature culling of affected animals. Mastitis-related economic losses in the United States are projected to be USD 2 billion annually, with each mastitis case costing producers an average of USD 326. In Israel, Holstein cows diagnosed with clinical mastitis caused by Escherichia coli had a decrease in daily milk yield of almost 15%, which is considered an average milk loss of about 200 liters per cow during the 305 days of the lactation period. In persistent infections, the loss of production is significantly higher; it is estimated at 1,500 liters of milk per cow with a decrease in daily production greater than 30%. In addition to its effects on dairy cattle, mastitis poses a threat to human health due to the risk of transmitting zoonotic pathogens through ingestion of contaminated milk or direct contact with infected cattle. Importantly, the emergence of antibiotic-resistant bacteria in milk and dairy products due to the indiscriminate use of antibiotics to treat bovine mastitis is a serious concern. Notably, E. coli is a leading cause of acute clinical mastitis in dairy cattle worldwide.

Escherichia coli comprises a highly heterogeneous group of commensal residents of the gut; however, because of the flexibility of its genome, this organism has evolved into pathogenic strains capable of causing diseases, including bovine mastitis following fecal contamination of the teat skin. Mammary pathogenic E. coli (MPEC) has been proposed as a new pathotype responsible for causing mastitis in dairy animals. The mammary gland is not a natural or primary habitat for E. coli because of the milk-associated innate immunity components, such as antimicrobial peptides, lysozyme, lactoferrin, and complement. However, some E. coli have acquired specific virulence factors (VFs) that might help the bacteria to invade the mammary gland, survive, and multiply in milk, turning the mammary gland into an amenable opportunistic habitat for these bacteria. Given the relevance of mastitis caused by E. coli, this paper reviews the important aspects of the disease, the characteristic of the etiologic agent E. coli, diagnosis, and treatments.

Clinical and Subclinical Mastitis

Based on disease symptoms, mastitis can be categorized into two different types, including clinical and subclinical. Clinical mastitis is characterized by visible abnormalities in the udder and milk. Physical examination of the affected mammary gland may reveal redness and pain upon palpation, swelling (edema), and induration (hardening). Systemic symptoms and behavioral changes, including fever, anorexia, depression, lethargy, and a reduction in grooming might also occur. Cattle with clinical mastitis are also affected by poor milk quality, as evidenced by increased somatic cell count (SCC) and compositional changes in milk. SCC is higher compared to the typical counts of under 200,000 cells/mL. The compositional changes in milk include the reduction of lactose content, but little effect on fat and protein contents was observed. Clots and flakes can appear in milk, as well as clear serum-like or bloody discharges. From 1996 to 2014, the reported incidence of clinical mastitis in United States dairy farms increased from 13% (USDA, 1996) to 25%. E. coli is one of the most common causes of clinical bovine mastitis, usually associated with acute symptoms such as dysstasia, diarrhea, and cool extremities. E. coli causes predominantly acute infections, of short duration (10–30 days), mainly in the last 2 weeks of the dry period and in the first weeks postpartum, although reinfections may occur throughout lactation. In most cases, E. coli is eliminated by the host immune response. However, severe cases with systemic involvement are difficult to treat and have a reserved prognosis.

Subclinical mastitis rarely poses an immediate threat to the animal’s life and is 15–40 times more common than clinical mastitis. This form of the disease cannot be detected by visual inspection of the udder or milk since both appear normal. Consequently, due to the concealed nature of the disease, dairy farmers are unaware of the extent of milk quality loss and the risk of subclinical mastitis spreading to other cows in the herd. Subclinical mastitis is mostly caused by gram-negative bacteria, such as E. coli, Klebsiella pneumoniae, and Serratia marcescens. These pathogens can be transmitted from an infected quarter to an uninfected quarter within the same animal or a different cattle by milking machine (e.g., teat cup liners), dirty milkers’ hands or gloves, and udder washcloths during the milking process. Subclinical mastitis is the most important intramammary illness in cattle, and it costs the dairy farmer more than clinical mastitis due to the dramatic decrease in milk production and quality.

The Dilemma of Mammary Pathogenic Escherichia coli as a New Pathotype

Extraintestinal pathogenic E. coli (ExPEC) include different sub-groups, e.g., uropathogenic E. coli (UPEC), meningitis-associated E. coli (MNEC), and sepsis-associated E. coli (SEPEC), causing urinary tract infection, meningitis, peritonitis, and septicemia, respectively. This E. coli pathotype-based classification is based on the site of infection, symptoms of the disease, and types of VFs. A novel ExPEC pathotype known as MPEC, one of the most common etiologic agents of bovine mastitis, has been suggested. Compared to other bacteria like Campylobacter spp., Clostridium spp., and Ruminococcus spp., MPEC have undergone evolutionary adaptations (e.g., acquisition of VFs) that improve its colonization of the unique environmental niches found within the mammary gland. These niches include competing microbes, soluble and cellular antimicrobials in milk, e.g., lactoferrin and lactoperoxidase, and the innate response elicited by immune cells. Consequently, E. coli with specific VFs selected within the mammary gland are better suited to cause bovine mastitis.

Some research studies found that E. coli isolated from cows with mastitis is less genotypically diverse than the environmental strains, and they mostly lack known E. coli VFs. This lack of VFs not only reflects the genome plasticity of E. coli but, most importantly, it suggests that mastitis-associated E. coli may have undergone some selective pressure based on the presence of specific VFs associated with the ability to survive in milk. However, despite recent publications focusing on E. coli genomes isolated from mastitis-affected cattle, researchers were unable to agree upon a common genetic group of putative VFs to all MPEC isolates. Importantly, genome studies on mastitis-associated E. coli have been questioned by some investigators, who argue the need to simultaneously analyze the host-pathogen interaction. For example, it is important to associate physiological traits with genomic data, including techniques such as dual RNA-Seq of the host and bacteria, Tn-Seq to test virulence association of genes in vivo, comparative SNP analysis of orthologous genes and intergenic regions, proteomics, and metabolomics.

Several research studies suggest that E. coli isolated from mastitis-affected cattle are naturally occurring commensals from the gastrointestinal tract of bovine, mostly from phylogroups A and B1. In other words, it is more likely that E. coli’s VFs implicated in bovine mastitis have their principal function in the colonization and survival in the highly diverse gastrointestinal environment. Consequently, E. coli isolated from mastitis-affected cattle are more likely to be opportunistic and might infect only cattle with a deficient immune system, particularly during the peripartum when leukocyte recruitment to the mammary gland is reduced. In this case, environmental variables and the cattle predispositions (e.g., innate immune system related to the health status, stage of lactation, and parity) are more important than the invading E. coli’s VFs in determining the severity of mastitis.

Table 1 shows studies on different virulence genes and VFs examined in E. coli isolates from bovine mastitis. Various virulence-related features have been suggested to explain the pathogenicity of E. coli in bovine mastitis, including but not limited to the activation of the innate immune system by pathogen-associated molecular patterns (PAMPs), resistance to serum and neutrophil killing, adhesion and invasion of mammary epithelial cells, and survival and proliferation in milk though secretion system. However, it is important to note that although the aforementioned virulence-associated properties benefit E. coli to thrive in the mammary gland environment, they are not unique to mastitis-associated E. coli, but are also common in ExPEC. Moreover, E. coli strains isolated from cattle with mastitis usually do not present the same virulence characteristics, demonstrating the high genetic abundance and variability of mastitis-causing E. coli.

Interestingly, the iron scavenging by the ferric dicitrate system has been shown to be strongly associated with mastitis-associated E. coli. The Fec system is essential for the growth of E. coli in milk and may influence disease severity in infections. Iron in bovine milk is limited and kept at quantities below those required to enable E. coli growth because most iron is attached to citrate and a lesser amount to lactoferrin, transferrin, xanthine oxidase, and certain caseins. To overcome the low amount of free iron in milk, E. coli expresses a variety of iron transport systems, such as the high-affinity siderophores (e.g., enterobactin, aerobactin, ferrichrome) and iron-regulated outer membrane proteins (IROMP) that bind to ferric siderophore complexes for transportation into the bacterial cell. In a population-level genomic analysis, showed that the Fec system is required for the pathogenicity of E. coli in the udder environment, as the prototypical MPEC strain P4 was unable to induce mastitis without the system, and the non-mammary gland-pathogenic K71 strain gained MPEC capability with its addition. Importantly, while additional research is needed to fully comprehend the significance of the Fec system in mastitis-associated E. coli, this critical structural component is a promising target for novel chemotherapeutics, enhanced mastitis therapy medicines, and novel vaccines.

Virulence Attributes of Escherichia coli Associated With the Severity of Mastitis

The impact of known virulence genes on the severity of bovine mastitis caused by E. coli is currently unclear, and numerous virulence gene profiles have been found in both persistent and transient isolates, suggesting a high genotypic variability of mastitis-associate E. coli. Importantly, clinical symptoms of E. coli mastitis may be related to genes that have yet to be discovered or to characteristics related to the host (e.g., stage of lactation, number and function of circulating neutrophils, SCC, age of the cattle, nutritional and metabolic status, and genetic resistance). However, persistent infections seem to be related to particular traits, especially the ability of E. coli to transfer from milk to mammary epithelial cells and survive intracellularly. Epithelial cell adhesion and invasion are important events in chronic or persistent infection. In vitro studies demonstrated that persistent mastitis-associated E. coli strains have a higher ability to adhere, invade and survive in bovine mammary epithelial cells line MAC-T than transient strains, are more capable of penetrating an endosome-like compartment of mammary epithelial cells, and have a different intracellular trafficking mechanism than transient strains. Moreover, it was shown that persistent E. coli isolates were more likely to carry lpf genes (encodes for long polar fimbriae), which correlates with E. coli’s ability to invade mammary epithelial cells. Interestingly, in a host-pathogen gene expression study conducted by, both acute and persistent E. coli mastitis strains boosted immune response gene expression (e.g., IRF1, CD83, IL-1α, IL-6, IL-8, CCL20, CXCL 2, MHC 1, Casp 3, CFB), but the immune response increase was substantially greater in cells cocultured with the acute E. coli strain than in cells cocultured with the persistent strain. Similarly, other investigations reported greater up-regulation in immune response functions, inflammation, and antigen processing and presentation in the acute phase than in the chronic phase of bovine mastitis. The induction of a modest immune response by persistent strain is insufficient to eradicate the infection, allowing E. coli to survive in the mammary gland for a lengthy period.

Innate and Acquired Immunity of the Mammary Gland

Bovine innate immunity comprises physical barriers at the tip of the teat and elements such as neutrophils, macrophages, cytokines, natural killer (NK) cells, lactoferrin, and complement, that act predominantly in the early stages of E. coli infections. This variety of immune cell types constitutes the somatic cells (SC), with neutrophils being the predominant type at the beginning of inflammation, representing about 90% of the SC increase. When pathogens invade the mammary gland, they face the first line of cellular defense, such as phagocytosis by neutrophils, which usually respond promptly to the inflammatory process. As a result, the severity of mastitis is determined by the speed with which neutrophils are recruited to the site of infection and how effectively this cell type phagocytes the pathogen. Importantly, the efficacy of the innate response influences the incidence of new intramammary infections, clinical severity, and duration of the case. Another crucial component of the host’s innate immunity is lactoferrin, an iron-tropic glycoprotein with bacteriostatic properties produced by epithelial cells and leukocytes. In ruminants, lactoferrin has been shown to inhibit the multiplication of E. coli by binding to iron ions, making them unavailable for bacterial growth. Additionally, cytokines including interleukins (IL), colony-stimulating factor (CSF), interferon (IFN), and tumor necrosis factor (TNF) are crucial in the mammary gland innate defense. Cytokines are responsible for local signs of inflammation such as swelling, redness, pain, and systemic symptoms such as fever, tachycardia, increased respiratory rate, anorexia, and depression. When innate immunity is not efficient in fighting the infection, the specific (or acquired) immunity mediated by lymphocytes occurs. In response to the inflammation, antibodies produced by lymphocytes pass from the bloodstream to the milk due to increased vascular permeability of the gland. The inflammatory response to mastitis aims to eradicate the microorganism responsible for the infection, neutralize the pathogen’s toxins, and then regenerate injured udder tissue so that the volume of milk normally produced is quickly recovered.

Mammary Pathogenic Escherichia coli-Elicited Immune Response

The onset of mastitis occurs when MPEC penetrates through the teat canal, multiplies in the teat and gland cisterns, and spreads throughout the milk-producing glandular tissue (Figure 1A). Once inside the mammary gland, MPEC ferment lactose and use it as an energy source to multiply without adhering to the gland’s epithelial surface, remaining in the cisterns, ducts, and alveolar lumen. Some MPEC strains can adhere to the udder epithelium, causing chronic intramammary infections and recurrent cases of clinical mastitis. The multiplication and lysis of MPEC release LPS from the bacteria’s outer membrane (Figure 1B). LPS binds to the LPS binding protein (LBP), and the LPS-LBP complex binds to the cluster of differentiation (CD)-14, which leads the LPS to a toll-like receptor-4 (TLR) on the surface of macrophages (;; Figure 1C). When LPS binds to its respective TLR, an intracellular signaling cascade is activated, including the activation of nuclear factor kappa-beta (NF-κβ), which induces macrophages and mammary epithelial cells to synthesize pro-inflammatory cytokines [e.g., interleukin (IL)-1β, IL-1, IL-6, IL-8, and tumor necrosis factor (TNF-α)] and acute-phase proteins (e.g., serum amyloid A and haptoglobin) (;;;;;;;; Figure 1D). Importantly, TNF-α is the main mediator of endotoxic shock that occurs in cases of super-acute mastitis caused by coliforms.

Chemotactic factors, especially IL-8, recruit neutrophils from the bloodstream that function as phagocytes at the site of infection in the alveoli (; Figure 1E). The efficiency of neutrophils’ diapedesis and phagocytosis directly influence the evolution of the local inflammatory process and the severity of mastitis. Although opsonization is not essential for phagocytosis, immunoglobulins (Ig) such as IgG2 and IgM recognize MPEC through Fab-regions and bind to neutrophils via Fc-receptors on the plasma membrane, leading to phagocytosis in a “zipper mechanism”. The exposure of neutrophils to fat globules and casein leads to loss of cytoplasmic granules (reduced bactericidal activities) and altered morphology (rounding), eliminating pseudopods needed for phagocytosis (;;;; Figure 1F). Consequently, many neutrophils are necessary to cope with the reduced phagocytic capabilities and control the infection. During phagocytosis, neutrophils release chemicals, e.g., reactive oxygen species (ROS) and proteases, that eliminate MPEC but also injure mammary epithelial cells, resulting in a permanent decrease in milk production (;; Figure 1F). To minimize mammary tissue damage, neutrophils undergo programmed cell death (apoptosis) and release chemokines that attract macrophages to the site of infection (; Figure 1G). In the last step of the inflammatory reaction, macrophages quickly phagocytose apoptotic neutrophils (efferocytosis), minimizing the release of granular contents that damage the tissue (; Figure 1H); whereas in the mammary alveolar, dendritic cells are generally non-responsive to MPEC infection. However, when efferocytosis done by macrophages is ineffective, there is increased clearing of apoptotic neutrophils by dendritic cells. Curing of the mammary gland is only successful if minimal tissue damage occurs.

Bovine Mastitis Diagnosis

Clinical mastitis is easily detected by visible abnormalities in the udder (e.g., redness, swelling, increased temperature, and pain upon physical palpation) and milk (e.g., presence of clots to clear, serum-like, or bloody secretions). In subclinical mastitis, however, indirect inflammation measures must be used to detect the disease. Contrarily to clinical mastitis, the only visible sign of animals with subclinical mastitis is reduced milk production. Consequently, the diagnostic requires complementary tests based on the SCC of milk. The SCC is used as an indicator of mammary gland health and milk quality. Usually, healthy cows produce milk with less than 100,000 SCC/mL, while cows with mastitis have a minimum SCC of 200,000 SCC/mL. The California Mastitis Test (CMT) estimates the SCC on milk and can be performed at the cow-side to detect mastitis. Electronic SCC is another test performed on the total mixed (composite) milk from all quarters of each cow, and it helps track the progress of control programs. Microbiologic culture of milk from individual quarters or composite samples of individual animals is another tool to identify E. coli involved in clinical mastitis. However, since the number of bacteria may be too small to be identified by standard methods, bacteria are not detected in roughly 30% of samples. Repeated culture and specialized culture techniques may be required in these cases.

Improved Diagnosis of Escherichia coli Mastitis: Challenges and Future Approaches

Because of the high costs of E. coli mastitis and the importance of maintaining cattle’s health and well-being, early diagnosis is critical. As previously mentioned in Section “Bovine Mastitis Diagnosis,” SCC and CMT are techniques commonly used to diagnose bovine mastitis. Unfortunately, both techniques have drawbacks, including subjective interpretation of CMT results, which could result in false positives and negatives, and factors such as lactation number, milk yield, stress, season, and breed that could influence with SCC’s interpretation. As a result, genotypic approaches are also used to supplement phenotypic identification of bovine mastitis, providing a viable option for resolving issues such as false-negative results. For example, approximately 30% of clinical mastitis samples do not grow in bacterial culture; however, polymerase chain reaction (PCR) is sensitive to detect growth-inhibited and reduces false-negative results. Other molecular typing methods used for the identification of bovine mastitis pathogen at the species level include ribotyping and amplified fragment length polymorphism (AFLP); at the strain level, include restriction fragment length polymorphism (RFLP), pulsed-field gel electrophoresis (PFGE) typing, and multiple-locus variable-number tandem repeat analysis (MLVA); and at both species and strain levels include transfer DNA intergenic spacer length polymorphism and DNA sequencing of housekeeping genes. Another genotypic method is microarray technology, which can detect seven common species of mastitis-causing pathogens in as little as 6 h, with a sensitivity of 94.1% and a specificity of 100%.

New biomarkers for high sensitivity and specificity, rapid and efficient with a “cow-side” application, are among the development prospects for novel E. coli mastitis diagnosis techniques. For example, proteomic research has yielded data on protein expression patterns that can be used to find novel therapeutic targets (e.g., bacterial immunogenic proteins for vaccines) and diagnostic biomarkers for bovine mastitis. Importantly, a detection method’s suitability for routine mastitis diagnosis is determined by its specificity, sensitivity, cost, processing time, and ability to handle a large number of milk samples. Proteomic technique for accurate biomarkers is feasible for early identification of mastitis and treatment efficacy, as well as the discovery of possibly novel targets for alternative therapy development. These advancements, however, are still not suitable for routine diagnosis of bovine mastitis.

Bovine Mastitis Treatment and Control

Since mastitis results from the interaction of many different factors, especially milking procedures and cleanliness of the environment, there is no single way to treat and control the disease. The control of environmental mastitis is especially challenging because E. coli is ubiquitous in the cattle’s environment. Thus, good herd health management and environmental hygiene are the most critical factors in preventing this type of mastitis. Except for severe infections during the puerperal period, antibiotic therapy for coliform mastitis is not recommended due to the high spontaneous cure rates and the risk of antibiotic contamination of the bulk milk. Supportive care such as fluid therapy and treatment with steroidal or non-steroidal anti-inflammatory drugs (e.g., dexamethasone) should be the first treatment option. Parenteral administration of fluoroquinolones (e.g., enrofloxacin, danofloxacin, marbofloxacin) or third-generation cephalosporin (e.g., ceftiofur) is recommended to treat severe E. coli mastitis.

Another approach to prevent coliform mastitis is to boost the animal’s specific immunity through vaccination, particularly with the E. coli J5 vaccine. While the teat canal is the first line of defense against intramammary infections, milk neutrophils are the major immune defense when E. coli has already invaded the teat canal. When intramammary infections are not quickly controlled by neutrophils, allowing LPS and lipoproteins to escape into the bloodstream, antibodies in the blood serum must be present to neutralize these potent toxins. Thus, preventing coliform mastitis through vaccination aims to achieve high levels of effective anti-coliform antibodies and antitoxins, both in milk and in the bloodstream, and around the teat canal. Two mutant strains of bacteria, E. coli O111:B4 (J5) and Salmonella Typhimurium Re-17 have been used in commercial preparations to immunize cows against coliform mastitis. E. coli O111:B4 (J5) is a rough mutant strain with an incomplete “O” polysaccharide chain in the cell wall, exposing the homologous half of the LPS core antigen (Zaatout, 2021). When this antigen is exposed, it stimulates the synthesis of immunoglobulins (e.g., IgM, IgG1, IgG2) that cross-react with other bacteria’s core antigens, resulting in immunity and protection against a wide range of bacterial genera and strains. The J5 vaccination boosts blood and milk titers of specific antibodies against E. coli LPS, enhancing its opsonization. Importantly, neutrophils can phagocyte bacteria more effectively when pathogens are opsonized by antibodies. Vaccinations are often timed to correspond with the highest risk of acquiring mastitis by coliforms (e.g., pre- and immediate postpartum), with immunizations being carried out 30 days before delivery and in the first week following delivery. Increasing the cattle’s natural ability to fight infections in the mammary gland during periods of increased susceptibility is one alternative for reducing mastitis in dairy cows.

The outer membrane protein A (OmpA) has also been considered a potential antigen in the bovine mastitis vaccine associated with E. coli. OmpA is a crucial virulence factor in the pathogenesis of E. coli, playing a key role in pore and biofilm formation, host cell invasion, and multidrug resistance. For example, recombinant OmpA protein fragments could regulate the expression of cytokines, chemokines, nitric oxide synthase, and cyclooxygenase-2, preventing E. coli meningitis in mice. Moreover, OmpA has been found to reduce complement-dependent or phagocytic-dependent killing of OmpA-positive E. coli. Therefore, OmpA is a potential antigen in vaccine development and for the prevention of E. coli infection. However, despite current investigations on mastitis vaccine, there is limited information on OmpA as a viable vaccine antigen in mastitis-associated E. coli. Among the few studies on OmpA as a vaccine candidate in E. coli mastitis, investigated the immunogenicity of OmpA by immunizing cows with a recombinant protein (rEcOmpA) to potentially stimulate antibodies and cell-mediated immune responses. Interestingly, the intramammary immunization elicited antibodies (e.g., IgG1 and IgG2), but the antibodies could not interact with the mastitis-causing strain P4, implying that they were unable to reach the accessible regions of OmpA molecules located at the outside leaflet of the bacteria external membrane. Collectively, the aforementioned studies show that the potential of OmpA as a vaccine to prevent E. coli-associated bovine mastitis has yet to be determined.

Antimicrobial Resistance of Mastitis-Associated Escherichia coli

Antibiotics are crucial in curing serious cases of bovine mastitis caused by E. coli. Several antimicrobial agents have been approved in the United States to treat E. coli mastitis, such as tetracyclines, macrolides, sulphonamides, quinolones, and β-lactams. Unfortunately, antibiotic therapy has frequently been demonstrated to have little or no effect in treating clinical or subclinical mastitis caused by coliforms in cattle. This fact is evidenced by the increase in antimicrobial-resistant isolates and the growing number of recurrent and persistent mastitis cases, often caused by the same E. coli isolate. E. coli isolated from the milk of mastitis-affected cattle is resistant to numerous antibiotic classes, including but not limited to aminopenicillin (e.g., cloxacillin), polypeptide (e.g., bacitracin), lincosamide (e.g., lincomycin), and macrolide (e.g., erythromycin). In clinical mastitis, additional caution is advised when determining whether or not to treat cattle with antimicrobials, as antibiotics are not always essential, such as in cases of negative cultures and minor coliform infections. However, severe cases of mastitis caused by E. coli must be treated immediately following diagnosis due to endotoxin-induced shock.

Pathologic alterations in the mammary gland, such as necrosis and ischemia, might obstruct antimicrobial distribution in the udder parenchyma, preventing the antimicrobial from reaching the site of infection or reaching sub-inhibitory concentrations. Importantly, the ability of E. coli to form biofilms on the tissue surface of the infected mammary gland, thereby establishing an inherent resistance to several antimicrobials treatment, is one of the hypotheses to explain the emergence of recurring mastitis. E. coli is notorious for being a reservoir for antimicrobial resistance genes, and it has the ability to horizontally transmit such genes to other pathogenic bacteria. Investigations have shown that the most prevalent resistance genes found in mastitis-associated E. coli encode resistance to aminoglycoside (e.g., aadA), streptomycin (e.g., strA, strB), tetracycline (e.g., tetA, tetC), sulfonamide (e.g., sulI, sulII), ampicillin (e.g., ampC), and β-lactams (e.g., blaTEM, blaCTX-M). Importantly, the extended-spectrum β-lactamase enzymes (ESBL) are a major concern in the antibiotic resistance mechanism of E. coli mastitis. These enzymes are located in plasmids and can hydrolyze penicillin, third and fourth-generation cephalosporins, and monobactam antibiotics. The detection of ESBL-producing isolates is of concern due to the direct association between multi-resistant bacteria and high mortality rates in humans. There is a clear increase in the prevalence of ESBL E. coli intestinal carriage among healthy individuals worldwide (2.6% in 2003–2005 to 21.1% in 2015–2018; an average increase of 1.2% per year). Importantly, several countries, including China, Egypt, Germany, and Greece, have been reporting the occurrence of ESBL-producing E. coli in cattle with mastitis. Moreover, the presence of ESBL-producing E. coli in milk raises concerns about the risks of ingesting unpasteurized milk and dairy products, potentially transmitting ESBL-producing E. coli to humans. The prevalence of these isolates in milk has ranged from 0.4% to 25.4%.

Tests used to verify the antimicrobial sensitivity of pathogens causing mastitis, including antibiogram, disc diffusion technique, and minimum inhibitory concentration (MIC), are alternatives for the rational use of antimicrobials, aiming to support the treatment only of quarters infected by agents with the possibility of cure. Nowadays, laboratories’ most often used method is the MIC, which produces more accurate findings than the antibiogram. This technique, however, does not yield reliable results when assessing sessile cells since sensitivity studies on bacteria organized in biofilms reveal that the concentration of antibiotics necessary for biofilm eradication is several times larger than that determined by MIC.

Conclusion

Under field conditions, colonization of the mammary gland is a polymicrobial event. Since milk is an excellent growth medium, many species of bacteria grow on it, colonize the mammary gland, and elicit inflammation and disease. Nevertheless, most mastitis cases are attributed to a single bacterial species or even to a single strain or clone of a species. The ability of E. coli to acquire exogenous DNA, including virulence genes, contributes to the development of pathogenic strains adapted to the mammary gland and potentially cause mastitis. MPEC has been proposed as a new pathotype responsible for causing mastitis in dairy animals. Some mastitis-associated E. coli strains evolved mechanisms that enable them to compete with other bacteria co-infecting the gland and evading the protective mechanisms of the host. However, it is important to note that although the aforementioned virulence-associated properties benefit E. coli to thrive in the mammary gland environment, they are not unique to mastitis-associated E. coli, but are also common in ExPEC. It is crucial to understand the principles behind the infection strategy of E. coli so that new approaches to treat and prevent mastitis by this bacteria and perhaps other mammary pathogens can be developed. The use of antibiotics in farm animals and specifically to treat mastitis is gradually precluded, and thus new treatment and prevention strategies are needed.

Author Contributions

DG and MM wrote the manuscript. DG developed figure and table. MM revised manuscript. Both authors contributed to the article and approved the submitted version.

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher’s Note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

References 245

  1. 1.

    Adkins P. R. F. Middleton J. (2018 ). Methods for diagnosing mastitis. Vet. Clin. N. Am. Food Anim. Pr. 34 479–491.

    Not in our library10.1016/j.cvfa.2018.07.003

  2. 2.

    Ahmed W. Neubauer H. Tomaso H. El Hofy F. I. Monecke S. El-Tawab (2021 ). Characterization of enterococci-and ESBL-producing Escherichia coli isolated from milk of bovides with mastitis in Egypt. Pathogens 10 97.

    Not in our library10.3390/pathogens10020097

  3. 3.

    Aitken S. L. Corl C. M. Sordillo L. M. (2011 ). Immunopathology of mastitis: insights into disease recognition and resolution. J. Mammary Gland Biol. Neoplasia 16 291–304.

    Not in our library10.1007/s10911-011-9230-4

  4. 4.

    Akers R. M. Nickerson S. C. (2011 ). Mastitis and its impact on structure and function in the ruminant mammary gland. J. Mammary Gland Biol. Neoplasia 16 275–289.

    Not in our library10.1007/s10911-011-9231-3

  5. 5.

    Akhtar M. Guo S. Guo Y. Zahoor A. Shaukat A. Chen Y. (2020 ). Upregulated-gene expression of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) via TLRs following NF-κB and MAPKs in bovine mastitis. Acta Trop. 207:105458.

    Not in our library10.1016/j.actatropica.2020.105458

  6. 6.

    Alamdari E. K. Ehsani M. R. (2017 ). Antimicrobial peptides derived from milk: a review. J. Food Biosci. Technol. 7 49–56.

    Not in our library

  7. 7.
  8. 8.

    Alhussien M. Manjari P. Mohammed S. Sheikh A. A. Reddi S. Dixit S. (2016 ). Incidence of mastitis and activity of milk neutrophils in Tharparkar cows reared under semi-arid conditions. Trop. Anim. Heal. Prod. 48 1291–1295.

    Not in our library10.1007/s11250-016-1068-8

  9. 9.

    Ali T. Rahman S. Zhang L. Shahid M. Zhang S. Liu G. (2016 ). ESBL-producing Escherichia coli from cows suffering mastitis in China contain clinical class 1 integrons with CTX-M linked to ISCR1. Front. Microbiol. 7:1931.

    Not in our library10.3389/fmicb.2016.01931

  10. 10.

    Ali T. Rahman S. Zhang L. Shahid M. Han D. (2017 ). Characteristics and genetic diversity of multi-drug resistant Escherichia coli isolated from bovine mastitis. Oncotarget 8 90144–90163.

    Not in our library10.18632/oncotarget.21496

  11. 11.

    Almeida R. A. Dogan B. Klaessing S. Schukken Y. H. Oliver S. P. (2011 ). Intracellular fate of strains of Escherichia coli isolated from dairy cows with acute or chronic mastitis. Vet. Res. Commun. 35 89–101.

    Not in our library10.1007/s11259-010-9455-5

  12. 12.

    Aslam N. Khan S. U. H. Usman T. Ali T. (2021 ). Phylogenetic genotyping, virulence genes and antimicrobial susceptibility of Escherichia coli isolates from cases of bovine mastitis. J. Dairy Res. 88 78–79.

    Not in our library10.1017/s002202992100011x

  13. 13.

    Azevedo C. Pacheco D. Soares L. Romão R. Moitoso M. Maldonado J. (2016 ). Prevalence of contagious and environmental mastitis-causing bacteria in bulk tank milk and its relationships with milking practices of dairy cattle herds in São Miguel Island (Azores). Trop. Anim. Health Prod. 48 451–459.

    Not in our library10.1007/s11250-015-0973-6

  14. 14.

    Bag M. A. S. Khan M. S. R. Sami M. D. H. Begum F. Islam M. S. Rahman M. M. (2021 ). Virulence determinants and antimicrobial resistance of E. coli isolated from bovine clinical mastitis in some selected dairy farms of Bangladesh. Saudi J. Biol. Sci. 28 6317–6323.

    Not in our library10.1016/j.sjbs.2021.06.099

  15. 15.

    Barlow J. (2011 ). Mastitis therapy and antimicrobial susceptibility: a multispecies review with a focus on antibiotic treatment of mastitis in dairy cattle. J Mammary Gland Biol. Neoplasia 16 383–407.

    Not in our library10.1007/s10911-011-9235-z

  16. 16.

    Bassel L. L. Caswell J. L. (2018 ). Bovine neutrophils in health and disease. Cell Tissue Res. 371 617–637.

    Not in our library10.1007/s00441-018-2789-y

  17. 17.

    Bathla S. Sindhu A. Kumar S. Dubey S. K. Pattnaik S. Rawat P. (2020 ). Tandem Mass Tag (TMT)-based quantitative proteomics reveals potential targets associated with onset of Sub-clinical Mastitis in cows. Sci. Rep. 10 1–10.

    Not in our library10.1038/s41598-020-66211-6

  18. 18.

    Bean A. Williamson J. Cursons R. T. (2004 ). Virulence genes of Escherichia coli strains isolated from mastitic milk. J. Vet. Med. B Infect. Dis. Vet. Public Health 51 285–287.

    Not in our library10.1111/j.1439-0450.2004.00772.x

  19. 19.

    Becheva Z. Gabrovska K. Godjevargova T. (2017 ). Immunofluorescence microscope assay of neutrophils and somatic cells in bovine milk. Food Agric. Immunol. 28 1196–1210.

    Not in our library10.1080/09540105.2017.1332012

  20. 20.

    Bengtsson B. Unnerstad H. E. Ekman T. Artursson K. Nilsson-Öst M. Waller K. P. (2009 ). Antimicrobial susceptibility of udder pathogens from cases of acute clinical mastitis in dairy cows. Vet. Microbiol. 136 142–149.

    Not in our library10.1016/j.vetmic.2008.10.024

  21. 21.

    Bezabih Y. M. Sabiiti W. Alamneh E. Bezabih A. Peterson G. M. Bezabhe W. M. (2021 ). The global prevalence and trend of human intestinal carriage of ESBL-producing Escherichia coli in the community. J. Antimicrob. Chemother. 76 22–29.

    Not in our library10.1093/jac/dkaa399

  22. 22.

    Bezman D. Lemberskiy-Kuzin L. Katz G. Merin U. Leitner G. (2015 ). Influence of intramammary infection of a single gland in dairy cows on the cow’s milk quality. J. Dairy Res. 82 304–311.

    Not in our library10.1017/s002202991500031x

  23. 23.

    Bhattarai D. Worku T. Dad R. Rehman Z. U. Gong X. Zhang S. (2018 ). Mechanism of pattern recognition receptors (PRRs) and host pathogen interplay in bovine mastitis. Microb. Pathog. 120 64–70.

    Not in our library10.1016/j.micpath.2018.04.010

  24. 24.

    Bhutto A. L. Murray R. D. Woldehiwet Z. (2012 ). California mastitis test scores as indicators of subclinical intra-mammary infections at the end of lactation in dairy cows. Res. Vet. Sci. 92 13–17.

    Not in our library10.1016/j.rvsc.2010.10.006

  25. 25.

    Bianchi R. M. Schwertz C. I. de Cecco B. S. Panziera W. De Lorenzo C. Heck L. C. (2019 ). Pathological and microbiological characterization of mastitis in dairy cows. Trop. Anim. Heal. Prod. 51 2057–2066.

    Not in our library10.1007/s11250-019-01907-0

  26. 26.

    Biran D. Ron E. Z. (2018 ). “Extraintestinal pathogenic Escherichia coli’,” in Escherichia Coli, a Versatile Pathogen, eds Frankel G. Ron E. Z. (Switzerland: Springer), 149–161.

    Not in our library10.1007/82_2018_108

  27. 27.

    Blum S. E. Leitner G. (2013 ). Genotyping and virulence factors assessment of bovine mastitis Escherichia coli. Vet. Microbiol. 163 305–312.

    Not in our library10.1016/j.vetmic.2012.12.037

  28. 28.

    Blum S. E. Goldstone R. J. Connolly J. P. R. Répérant-Ferter M. Germon P. Inglis N. F. (2018 ). Postgenomics characterization of an essential genetic determinant of mammary pathogenic Escherichia coli. MBio 9:e423–e418.

    Not in our library10.1128/mbio.00423-18

  29. 29.

    Blum S. E. Heller E. D. Leitner G. (2014 ). Long term effects of Escherichia coli mastitis. Vet. J. 201 72–77.

    Not in our library10.1016/j.tvjl.2014.04.008

  30. 30.

    Blum S. E. Heller E. D. Jacoby S. Krifucks O. Leitner G. (2017 ). Comparison of the immune responses associated with experimental bovine mastitis caused by different strains of Escherichia coli. J. Dairy Res. 84 190–197.

    Not in our library10.1017/s0022029917000206

  31. 31.

    Blum S. E. Heller E. D. Krifucks O. Sela S. Hammer-Muntz O. Leitner G. (2008 ). Identification of a bovine mastitis Escherichia coli subset. Vet. Microbiol. 132 135–148.

    Not in our library10.1016/j.vetmic.2008.05.012

  32. 32.

    Blum S. E. Heller E. D. Sela S. Elad D. Edery N. Leitner G. (2015 ). Genomic and phenomic study of mammary pathogenic Escherichia coli. PLoS One 10:e0136387.

    Not in our library10.1371/journal.pone.0136387

  33. 33.

    Bobbo T. Ruegg P. L. Stocco G. Fiore E. Gianesella M. Morgante M. (2017 ). Associations between pathogen-specific cases of subclinical mastitis and milk yield, quality, protein composition, and cheese-making traits in dairy cows. J. Dairy Sci. 100 4868–4883.

    Not in our library10.3168/jds.2016-12353

  34. 34.

    Boireau C. Cazeau G. Jarrige N. Calavas D. Madec J. Y. Leblond A. (2018 ). Antimicrobial resistance in bacteria isolated from mastitis in dairy cattle in France, 2006–2016. J. Dairy Sci. 101 9451–9462.

    Not in our library10.3168/jds.2018-14835

  35. 35.
  36. 36.

    Brade L. Hensen S. Brade H. (2013 ). Evaluation of a LPS-based glycoconjugate vaccine against bovine Escherichia coli mastitis: formation of LPS Abs in cows after immunization with E. coli core oligosaccharides conjugated to hemocyanine. Innate Immun. 19 368–377.

    Not in our library10.1177/1753425912462615

  37. 37.

    Bradley A. J. Green M. J. (2000 ). A study of the incidence and significance of intramammary enterobacterial infections acquired during the dry period. J. Dairy Sci. 83 1957–1965.

    Not in our library10.3168/jds.s0022-0302(00)75072-7

  38. 38.

    Brandt M. Haeussermann A. Hartung E. (2010 ). Invited review: technical solutions for analysis of milk constituents and abnormal milk. J. Dairy Sci. 93 427–436.

    Not in our library10.3168/jds.2009-2565

  39. 39.

    Bronzo V. Lopreiato V. Riva F. Amadori M. Curone G. Addis M. F. (2020 ). The role of innate immune response and microbiome in resilience of dairy cattle to disease: the mastitis model. Animals 10 1–20.

    Not in our library10.3390/ani10081397

  40. 40.
  41. 41.

    Burvenich C. Merris V. Mehrzad J. Diez-Fraile A. Duchateau L. (2003 ). Severity of E. coli mastitis is mainly determined by cow factors. Vet. Res. 34 521–564.

    Not in our library10.1051/vetres:2003023

  42. 42.

    Bush K. Jacoby G. A. (2010 ). Updated functional classification of β-lactamases. Antimicrob. Agents Chemother. 54 969–976.

    Not in our library10.1128/aac.01009-09

  43. 43.

    Cao H. Pradhan A. K. Karns J. S. Hovingh E. Wolfgang D. R. Vinyard B. T. (2019 ). Age-associated distribution of antimicrobial-resistant salmonella enterica and Escherichia coli isolated from dairy herds in Pennsylvania, 2013-2015. Foodborne Pathog. Dis. 16 60–67.

    Not in our library10.1089/fpd.2018.2519

  44. 44.

    Ceciliani F. Eckersall D. Burchmore R. Lecchi C. (2014 ). Proteomics in veterinary medicine: applications and trends in disease pathogenesis and diagnostics. Vet. Pathol. 51 351–362.

    Not in our library10.1177/0300985813502819

  45. 45.

    Chakraborty S. Dhama K. Tiwari R. Iqbal Yatoo M. Khurana S. K. Khandia R. (2019 ). Technological interventions and advances in the diagnosis of intramammary infections in animals with emphasis on bovine population—a review. Vet Q 39 76–94.

    Not in our library10.1080/01652176.2019.1642546

  46. 46.

    Chen, Chen, Wu N. Rong N. Kang C. Chen (2020 ). Immunoprotective evaluation of Escherichia coli outer membrane protein A against the main pathogens of animal mastitis. Trop. J. Pharm. Res. 19 155–162.

    Not in our library10.4314/tjpr.v19i1.23

  47. 47.

    Cheng J. Qu W. Barkema H. W. Nobrega D. B. Gao J. Liu G. (2019 ). Antimicrobial resistance profiles of 5 common bovine mastitis pathogens in large Chinese dairy herds. J. Dairy Sci 102 2416–2426.

    Not in our library10.3168/jds.2018-15135

  48. 48.

    Chengolova Z. Atanasova M. Godjevargova T. (2021 ). Neutrophil and CD4+milk cell count related to natural incidence of mastitis in Jersey cattle. J. Dairy Sci 88 334–336.

    Not in our library10.1017/s0022029921000510

  49. 49.
  50. 50.

    Confer A. W. Ayalew S. (2013 ). The OmpA family of proteins: roles in bacterial pathogenesis and immunity. Vet. Microbiol 163 207–222.

    Not in our library10.1016/j.vetmic.2012.08.019

  51. 51.

    Costa A. Lopez-Villalobos N. Sneddon N. W. Shalloo L. Franzoi M. De Marchi M. (2019 ). Invited review: milk lactose-current status and future challenges in dairy cattle. J. Dairy Sci. 102 5883–5898.

    Not in our library10.3168/jds.2018-15955

  52. 52.

    Croxen M. A. Finlay B. B. (2010 ). Molecular mechanisms of Escherichia coli pathogenicity. Nat. Rev. Microbiol. 8 26–38.

    Not in our library10.1038/nrmicro2265

  53. 53.

    Curone G. Filipe J. Cremonesi P. Trevisi E. Amadori M. Pollera C. (2018 ). What we have lost: mastitis resistance in Holstein Friesians and in a local cattle breed. Res. Vet. Sci. 116 88–98.

    Not in our library10.1016/j.rvsc.2017.11.020

  54. 54.

    Dahmen S. Métayer V. Gay E. Madec J. Y. Haenni M. (2013 ). Characterization of extended-spectrum beta-lactamase (ESBL)-carrying plasmids and clones of Enterobacteriaceae causing cattle mastitis in France. Vet. Microbiol. 162 793–799.

    Not in our library10.1016/j.vetmic.2012.10.015

  55. 55.

    Denamur E. Clermont O. Bonacorsi S. Gordon D. (2021 ). The population genetics of pathogenic Escherichia coli. Nat. Rev. Microbiol. 19 37–54.

    Not in our library10.1038/s41579-020-0416-x

  56. 56.

    Dittrich I. Gertz M. Krieter J. (2019 ). Alterations in sick dairy cows’ daily behavioural patterns. Heliyon 5:e02902.

    Not in our library10.1016/j.heliyon.2019.e02902

  57. 57.

    Dogan B. Klaessig S. Rishniw M. Oliver S. Simpson K. Schukken Y. (2006 ). Adherent and invasive Escherichia coli are associated with persistent bovine mastitis. Vet. Microbiol. 116 270–282.

    Not in our library10.1016/j.vetmic.2006.04.023

  58. 58.

    Dogan B. Rishniw M. Bruant G. Harel J. Schukken Y. H. Simpson K. W. (2012 ). Phylogroup and lpfA influence epithelial invasion by mastitis associated Escherichia coli. Vet. Microbiol. 159 163–170.

    Not in our library10.1016/j.vetmic.2012.03.033

  59. 59.

    Duarte C. M. Freitas P. P. Bexiga R. (2015 ). Technological advances in bovine mastitis diagnosis: an overview. J. Vet. Diagn. Investig. 27 665–672.

    Not in our library10.1177/1040638715603087

  60. 60.

    Eckel E. F. Ametaj B. N. (2020 ). Bacterial endotoxins and their role in periparturient diseases of dairy cows: mucosal vaccine perspectives. MDPI Dairy 1 61–90.

    Not in our library10.3390/dairy1010006

  61. 61.

    Eisenberger D. Carl A. Balsliemke J. Kämpf P. Nickel S. Schulze G. (2018 ). Molecular characterization of extended-spectrum β-lactamase-producing Escherichia coli isolates from milk samples of dairy cows with mastitis in Bavaria, Germany. Microb. Drug Resist. 24 505–510.

    Not in our library10.1089/mdr.2017.0182

  62. 62.

    Elazar S. Gonen E. Livneh-Kol A. Rosenshine I. Shpigel N. Y. (2010 ). Essential role of neutrophils but not mammary alveolar macrophages in a murine model of acute Escherichia coli mastitis. Vet. Res 41:53.

    Not in our library10.1051/vetres/2010025

  63. 63.

    El-Sayed A. Kamel M. (2021 ). Bovine mastitis prevention and control in the post-antibiotic era. Trop. Anim. Heal. Prod. 53:236.

    Not in our library10.1007/s11250-021-02680-9

  64. 64.

    El-Sayed A. Awad W. Abdou N. E. Castañeda Vázquez H. (2017 ). Molecular biological tools applied for identification of mastitis causing pathogens. Int. J. Vet. Sci. 5 89–97.

    Not in our library10.1016/j.ijvsm.2017.08.002

  65. 65.

    Elsayed M. S. A. E. Eldsouky S. M. Roshdy T. Bayoume A. M. A. Nasr G. M. Salama A. S. A. (2021 ). Genetic and antimicrobial resistance profiles of non-O157 shiga toxin-producing Escherichia coli from different sources in Egypt. BMC Microbiol. 21:1–19.

    Not in our library10.1186/s12866-021-02308-w

  66. 66.

    Erskine R. J. (2012 ). Vaccination strategies for mastitis. Vet. Clin. N. Am. - Food Anim. Pr. 28 257–270.

    Not in our library10.1016/j.cvfa.2012.03.002

  67. 67.

    Erskine R. J. VanDyk E. J. Bartlett P. C. Burton J. L. Boyle M. C. (2007 ). Effect of hyperimmunization with an Escherichia coli J5 bacterin in adult lactating dairy cows. J. Am. Vet. Med. Assoc. 231 1092–1097.

    Not in our library10.2460/javma.231.7.1092

  68. 68.

    Fairbrother J. H. Dufour S. Fairbrother J. M. Francoz D. Nadeau É Messier S. (2015 ). Characterization of persistent and transient Escherichia coli isolates recovered from clinical mastitis episodes in dairy cows. Vet. Microbiol. 176 126–133.

    Not in our library10.1016/j.vetmic.2014.12.025

  69. 69.

    Fazel F. Jamshidi A. Khoramian B. (2019 ). Phenotypic and genotypic study on antimicrobial resistance patterns of E. coli isolates from bovine mastitis. Microb. Pathog. 132 355–361.

    Not in our library10.1016/j.micpath.2019.05.018

  70. 70.

    Fernandes J. B. C. Zanardo L. G. Galvão N. N. Carvalho I. A. Nero L. A. Moreira M. A. S. (2011 ). Escherichia coli from clinical mastitis: serotypes and virulence factors. J. Vet. Diagn. Investig. 23 1146–1152.

    Not in our library10.1177/1040638711425581

  71. 71.
  72. 72.

    Filioussis G. Kachrimanidou M. Christodoulopoulos G. Kyritsi M. Hadjichristodoulou C. Adamopoulou M. (2020 ). Short communication: bovine mastitis caused by a multidrug-resistant, mcr-1-positive (colistin-resistant), extended-spectrum β-lactamase–producing Escherichia coli clone on a Greek dairy farm. J. Dairy Sci. 103 852–857.

    Not in our library10.3168/jds.2019-17320

  73. 73.

    Finlay B. B. Cossart P. (1997 ). Exploitation of mammalian host cell functions by bacterial pathogens. Science 276 718–725.

    Not in our library10.1126/science.276.5313.718

  74. 74.

    Fitzgerald D. C. Meade K. G. McEvoy A. N. Lillis L. Murphy E. P. MacHugh D. E. (2007 ). Tumour necrosis factor-α (TNF-α) increases nuclear factor κB (NFκB) activity in and interleukin-8 (IL-8) release from bovine mammary epithelial cells. Vet. Immunol. Immunopathol. 116 59–68.

    Not in our library10.1016/j.vetimm.2006.12.008

  75. 75.

    Fosgate G. T. Petzer I. M. Karzis J. (2013 ). Sensitivity and specificity of a hand-held milk electrical conductivity meter compared to the California mastitis test for mastitis in dairy cattle. Vet. J. 196 98–102.

    Not in our library10.1016/j.tvjl.2012.07.026

  76. 76.

    Freitag C. Michael G. B. Kadlec K. Hassel M. Schwarz S. (2017 ). Detection of plasmid-borne extended-spectrum β-lactamase (ESBL) genes in Escherichia coli isolates from bovine mastitis. Vet. Microbiol. 200 151–156.

    Not in our library10.1016/j.vetmic.2016.08.010

  77. 77.

    Fuenzalida M. J. Ruegg P. L. (2019 ). Negatively controlled, randomized clinical trial to evaluate intramammary treatment of nonsevere, gram-negative clinical mastitis. J. Dairy Sci. 102 5438–5457.

    Not in our library10.3168/jds.2018-16156

  78. 78.

    Gao J. Barkema H. W. Zhang L. Liu G. Deng Z. Cai L. (2017 ). Incidence of clinical mastitis and distribution of pathogens on large Chinese dairy farms. J. Dairy Sci. 100 4797–4806.

    Not in our library10.3168/jds.2016-12334

  79. 79.

    Ghanbarpour R. Oswald E. (2010 ). Phylogenetic distribution of virulence genes in Escherichia coli isolated from bovine mastitis in Iran. Res. Vet. Sci. 88 6–10.

    Not in our library10.1016/j.rvsc.2009.06.003

  80. 80.

    Godden S. M. Royster E. Timmerman J. Rapnicki P. Green H. (2017 ). Evaluation of an automated milk leukocyte differential test and the California Mastitis Test for detecting intramammary infection in early- and late-lactation quarters and cows. J. Dairy Sci. 100 6527–6544.

    Not in our library10.3168/jds.2017-12548

  81. 81.

    Goldstone R. J. Harris S. Smith D. G. E. (2016 ). Genomic content typifying a prevalent clade of bovine mastitis-associated Escherichia coli. Sci. Rep. 6 1–15.

    Not in our library10.1038/srep30115

  82. 82.

    Gonçalves J. L. Kamphuis C. Martins C. M. M. R. Barreiro J. R. Tomazi T. Gameiro A. H. (2018 ). Bovine subclinical mastitis reduces milk yield and economic return. Livest. Sci 210 25–32.

    Not in our library10.1016/j.livsci.2018.01.016

  83. 83.

    Gonen E. Vallon-Eberhard A. Elazar S. Harmelin A. Brenner O. Rosenshine I. (2007 ). Toll-like receptor 4 is needed to restrict the invasion of Escherichia coli P4 into mammary gland epithelial cells in a murine model of acute mastitis. Cell Microbiol. 9 2826–2838.

    Not in our library10.1111/j.1462-5822.2007.00999.x

  84. 84.

    Greenlee-Wacker M. C. (2016 ). Clearance of apoptotic neutrophils and resolution of inflammation. Immunol. Rev. 273 357–370.

    Not in our library10.1111/imr.12453

  85. 85.

    Guerra S. T. Orsi H. Joaquim S. F. Guimarães F. F. Lopes B. C. Dalanezi F. M. (2020 ). Short communication: investigation of extra-intestinal pathogenic Escherichia coli virulence genes, bacterial motility, and multidrug resistance pattern of strains isolated from dairy cows with different severity scores of clinical mastitis. J. Dairy Sci. 103 3606–3614.

    Not in our library10.3168/jds.2019-17477

  86. 86.

    Guerra S. Dalanezi F. Paula C. Hernandes R. Pantoja J. Listoni F. (2019 ). Putative virulence factors of extra-intestinal Escherichia coli isolated from bovine mastitis with different clinical scores. Lett. Appl. Microbiol. 68 403–408.

    Not in our library10.1111/lam.13113

  87. 87.
  88. 88.

    Hagiwara S. Mori K. Okada H. Oikawa S. Nagahata H. (2014 ). Acute Escherichia coli mastitis in dairy cattle: diagnostic parameters associated with poor prognosis. J. Vet. Med. Sci. 76 1431–1436.

    Not in our library10.1292/jvms.13-0610

  89. 89.

    Harrison R. (2006 ). Milk xanthine oxidase: properties and physiological roles. Int. Dairy J. 16 546–554.

    Not in our library10.1016/j.idairyj.2005.08.016

  90. 90.

    Heikkilä A. M. Liski E. Pyörälä S. Taponen S. (2018 ). Pathogen-specific production losses in bovine mastitis. J. Dairy Sci. 101 9493–9504.

    Not in our library10.3168/jds.2018-14824

  91. 91.

    Herry V. Gitton C. Tabouret G. Répérant M. Forge L. Tasca C. (2017 ). Local immunization impacts the response of dairy cows to Escherichia coli mastitis. Sci. Rep. 7 1–18.

    Not in our library10.1038/s41598-017-03724-7

  92. 92.

    Hogan J. Smith K. (2003 ). Coliform mastitis. Vet. Res. 34 507–519.

    Not in our library10.1051/vetres:2003022

  93. 93.

    Hogan J. Smith K. L. (2012 ). Managing environmental mastitis. Vet. Clin. North Am. Food. Anim. Pr. 28 217–224.

    Not in our library10.1016/j.cvfa.2012.03.009

  94. 94.

    Hogeveen H. Steeneveld W. Wolf C. A. (2019 ). Production diseases reduce the efficiency of dairy production: a review of the results, methods, and approaches regarding the economics of mastitis. Annu. Rev. Resour. Econ. 11 289–312.

    Not in our library10.1146/annurev-resource-100518-093954

  95. 95.

    Holko I. Tančin V. Vršková M. Tvarožková K. (2019 ). Prevalence and antimicrobial susceptibility of udder pathogens isolated from dairy cows in Slovakia. J. Dairy Res. 86 436–439.

    Not in our library10.1017/s0022029919000694

  96. 96.

    Hsieh W. S. Yang Y. Y. Lin P. H. Chang C. C. Wu H. H. (2016 ). Recombinant OmpA protein fragments mediate interleukin-17 regulation to prevent Escherichia coli meningitis. J. Microbiol. Immunol. Infect. 49 843–850.

    Not in our library10.1016/j.jmii.2015.05.019

  97. 97.
  98. 98.

    Ingvartsen K. L. Moyes K. M. (2015 ). Factors contributing to immunosuppression in the dairy cow during the periparturient period. J. Vet. Res. 63 15–24.

    Not in our library10.14943/jjvr.63.suppl.s15

  99. 99.

    Ismail Z. B. (2017 ). Mastitis vaccines in dairy cows: recent developments and recommendations of application. Vet. World 10 1057–1062.

    Not in our library10.14202/vetworld.2017.1057-1062

  100. 100.

    Jacoby G. A. (2009 ). AmpC B -Lactamases. Clin. Microbiol. Rev. 22 161–182.

    Not in our library10.1128/cmr.00036-08

  101. 101.

    Kaipainen T. Pohjanvirta T. Shpigel N. Y. Shwimmer A. Pyörälä S. Pelkonen S. (2002 ). Virulence factors of Escherichia coli isolated from bovine clinical mastitis. Vet. Microbiol. 85 37–46.

    Not in our library10.1016/s0378-1135(01)00483-7

  102. 102.
  103. 103.

    Kawai K. Kondo Y. Shinozuka Y. Kawata R. Kaneko S. Iwano H. (2020 ). Immune response during the onset of coliform mastitis in dairy cows vaccinated with STARTVAC®. J. Anim. Sci. 92:e13502.

    Not in our library10.1111/asj.13502

  104. 104.

    Kawai K. Korematsu K. Akiyama K. Okita M. Yoshimura Y. Isobe N. (2015 ). Dynamics of lingual antimicrobial peptide, lactoferrin concentrations and lactoperoxidase activity in the milk of cows treated for clinical mastitis. Anim. Sci. J. 86 153–158.

    Not in our library10.1111/asj.12269

  105. 105.

    Kayano M. Itoh M. Kusaba N. Hayashiguchi O. Kida K. Tanaka Y. (2018 ). Associations of the first occurrence of pathogen-specific clinical mastitis with milk yield and milk composition in dairy cows. J. Dairy Res. 85 309–316.

    Not in our library10.1017/s0022029918000456

  106. 106.

    Kayitsinga J. Schewe R. L. Contreras G. A. Erskine R. J. (2017 ). Antimicrobial treatment of clinical mastitis in the eastern United States: the influence of dairy farmers’ mastitis management and treatment behavior and attitudes. J. Dairy Sci. 100 1388–1407.

    Not in our library10.3168/jds.2016-11708

  107. 107.

    Kelly A. L. Leitner G. Merin U. (2011 ). “Milk quality and udder health: Test methods and standards’,” in Encyclopedia of Dairy Science, eds Fuquay J. W. Fox P. F. McSweeney P. L. H. (Cambridge, MA: Academic Press), 894–901.

    Not in our library10.1016/b978-0-12-374407-4.00353-8

  108. 108.

    Kempf F. Slugocki C. Blum S. E. Leitner G. Germon P. (2016 ). Genomic comparative study of bovine mastitis Escherichia coli. PLoS One 11:e0147954.

    Not in our library10.1371/journal.pone.0147954

  109. 109.

    Kerro Dego O. Oliver S. P. Almeida R. A. (2012 ). Host-pathogen gene expression profiles during infection of primary bovine mammary epithelial cells with Escherichia coli strains associated with acute or persistent bovine mastitis. Vet. Microbiol. 155 291–297.

    Not in our library10.1016/j.vetmic.2011.08.016

  110. 110.

    Kester H. J. Sorter D. E. Hogan J. S. (2015 ). Activity and milk compositional changes following experimentally induced Streptococcus uberis bovine mastitis. J. Dairy Sci. 98 999–1004.

    Not in our library10.3168/jds.2014-8576

  111. 111.

    Khan M. Z. Khan A. Xiao J. Ma J. Ma Y. Chen T. (2020 ). Overview of research development on the role of NF-κB signaling in mastitis. Animals 10 1–16.

    Not in our library10.3390/ani10091625

  112. 112.

    Kieckens E. Rybarczyk J. Cox E. Vanrompay D. (2018 ). Antibacterial and immunomodulatory activities of bovine lactoferrin against Escherichia coli O157:H7 infections in cattle. BioMetals 31 321–330.

    Not in our library10.1007/s10534-018-0082-x

  113. 113.

    Klaas I. C. Zadoks R. N. (2018 ). An update on environmental mastitis: challenging perceptions. Transbound. Emerg. Dis. 65 166–185.

    Not in our library10.1111/tbed.12704

  114. 114.

    Koshiishi T. Watanabe M. Miyake H. Hisaeda K. Isobe N. (2017 ). Cellular and soluble components decrease the viable pathogen counts in milk from dairy cows with subclinical mastitis. J. Vet. Med. Sci. 79 1389–1393.

    Not in our library10.1292/jvms.17-0269

  115. 115.

    Krishnan S. Prasadarao N. V. (2012 ). Outer membrane protein A and OprF: versatile roles in Gram-negative bacterial infections. FEBS J. 279 919–931.

    Not in our library10.1111/j.1742-4658.2012.08482.x

  116. 116.

    Krömker V. Leimbach S. (2017 ). Mastitis treatment—Reduction in antibiotic usage in dairy cows. Reprod. Domest. Anim. 52 21–29.

    Not in our library10.1111/rda.13032

  117. 117.

    Kuhi M. Aminlari M. Tavana M. (2021 ). Antibacterial action of dextran conjugated lysozyme against bacteria involved in bovine mastitis. Adv. Dairy. Res. 9 1–6.

    Not in our library

  118. 118.

    Kupczyński R. Bednarski M. Śpitalniak K. Pogoda-Sewerniak K. (2017 ). Effects of protein-iron complex concentrate supplementation on iron metabolism, oxidative and immune status in preweaning calves. Int. J. Mol. Sci. 18 1501–1512.

    Not in our library10.3390/ijms18071501

  119. 119.

    Lauzon K. Zhao X. Bouetard A. Delbecchi L. Paquette B. Lacasse P. (2005 ). Antioxidants to prevent bovine neutrophil-induced mammary epithelial cell damage. J. Dairy Sci. 88 4295–4303.

    Not in our library10.3168/jds.s0022-0302(05)73115-5

  120. 120.

    Le Gall T. Clermont O. Gouriou S. Picard B. Nassif X. Denamur E. (2007 ). Extraintestinal virulence is a coincidental by-product of commensalism in b2 phylogenetic group Escherichia coli strains. Mol. Biol. Evol. 24 2373–2384.

    Not in our library10.1093/molbev/msm172

  121. 121.

    Leblanc S. J. (2020 ). Relationships between metabolism and neutrophil function in dairy cows in the peripartum period. Animal 14 44–54.

    Not in our library10.1017/s1751731119003227

  122. 122.

    Lee K. H. Lee J. W. Wang S. W. Liu L. Y. Lee M. F. Chuang S. T. (2008 ). Development of a novel biochip for rapid multiplex detection of seven mastitis-causing pathogens in bovine milk samples. J. Vet. Diagn. Investig. 20 463–471.

    Not in our library10.1177/104063870802000408

  123. 123.

    Leimbach A. Poehlein A. Vollmers J. Görlich D. Daniel R. Dobrindt U. (2017 ). No evidence for a bovine mastitis Escherichia coli pathotype. BMC Genom. 18:1–22.

    Not in our library10.1186/s12864-017-3739-x

  124. 124.

    Leung K. T. Mackereth R. Tien Y. C. Topp E. (2004 ). A comparison of AFLP and ERIC-PCR analyses for discriminating Escherichia coli from cattle, pig and human sources. FEMS Microbiol. Ecol. 47 111–119.

    Not in our library10.1016/s0168-6496(03)00254-x

  125. 125.

    Li L. Chen X. Chen Z. (2019 ). Identification of key candidate genes in dairy cow in response to Escherichia coli mastitis by bioinformatical analysis. Front. Genet. 10:1251.

    Not in our library10.3389/fgene.2019.01251

  126. 126.

    Li Q. Chang W. Zhang H. Hu D. Wang X. (2019 ). The role of plasmids in the multiple antibiotic resistance transfer in ESBLs-producing Escherichia coli isolated from wastewater treatment plants. Front. Microbiol. 10:633.

    Not in our library10.3389/fmicb.2019.00633

  127. 127.

    Li W. Xue M. Yu L. Qi K. Ni J. Chen X. (2020 ). QseBC is involved in the biofilm formation and antibiotic resistance in Escherichia coli isolated from bovine mastitis. Peer J. 8 1–18.

    Not in our library10.7717/peerj.8833

  128. 128.

    Liang D. Arnold L. M. Stowe C. J. Harmon R. J. Bewley J. M. (2017 ). Estimating US dairy clinical disease costs with a stochastic simulation model. J. Dairy Sci. 100 1472–1486.

    Not in our library10.3168/jds.2016-11565

  129. 129.

    Lind M. Sipka A. S. Schuberth H. J. Blutke A. Wanke R. Sauter-Louis C. (2015 ). Location-specific expression of chemokines. TNF-α and S100 proteins in a teat explant model. Innate Immun. 21 322–331.

    Not in our library10.1177/1753425914539820

  130. 130.

    Lippolis J. D. Bayles D. O. Reinhardt T. A. (2009 ). Proteomic changes in Escherichia coli when grown in fresh milk versus laboratory media. J. Proteome Res. 8 149–158.

    Not in our library10.1021/pr800458v

  131. 131.

    Lippolis J. D. Brunelle B. W. Reinhardt T. A. Sacco R. E. Nonnecke B. J. Dogan B. (2014 ). Proteomic analysis reveals protein expression differences in Escherichia coli strains associated with persistent versus transient mastitis. J. Proteom. 108 373–381.

    Not in our library10.1016/j.jprot.2014.06.008

  132. 132.

    Liu X. Sun W. Wu N. Rong N. Kang C. Jian S. (2021 ). Synthesis of Escherichia coli ompA oral nanoparticles and evaluation of immune functions against the major etiologic agent of cow mastitis. Vaccines 9:304.

    Not in our library10.3390/vaccines9030304

  133. 133.

    Liu Y. Liu G. Liu W. Liu Y. Ali T. Chen W. (2014 ). Phylogenetic group, virulence factors and antimicrobial resistance of Escherichia coli associated with bovine mastitis. Res. Microbiol. 165 273–277.

    Not in our library10.1016/j.resmic.2014.03.007

  134. 134.

    Maity S. Ambatipudi K. (2021 ). Mammary microbial dysbiosis leads to the zoonosis of bovine mastitis: a One-Health perspective. FEMS Microbiol. Ecol. 97 fiaa241.

    Not in our library10.1093/femsec/fiaa241

  135. 135.

    Majumder S. Jung D. Ronholm J. George S. (2021 ). Prevalence and mechanisms of antibiotic resistance in Escherichia coli isolated from mastitic dairy cattle in Canada. BMC Microbiol. 21:1–14.

    Not in our library10.1186/s12866-021-02301-3

  136. 136.

    Makovec J. A. Ruegg P. L. (2003 ). Results of milk samples submitted for microbiological examination in Wisconsin from 1994 to 2001. J. Dairy Sci. 86 3466–3472.

    Not in our library10.3168/jds.s0022-0302(03)73951-4

  137. 137.

    Malik T. A. Mohini M. Mir S. H. Ganaie B. A. Singh D. Varun T. K. (2018 ). Somatic cells in relation to udder health and milk quality-A review. J. Anim. Heal. Prod. 6 18–26.

    Not in our library10.17582/journal.jahp/2018/6.1.18.26

  138. 138.

    Martins L. Barcelos M. M. Cue R. I. Anderson K. L. Santos M. V. (2020 ). Chronic subclinical mastitis reduces milk and components yield at the cow level. J. Dairy Res. 87 298–305.

    Not in our library10.1017/s0022029920000321

  139. 139.

    Mathew A. G. Cissell R. Liamthong S. (2007 ). Antibiotic resistance in bacteria associated with food animals: a United States perspective of livestock production. Foodborne Pathog. Dis. 4 115–133.

    Not in our library10.1089/fpd.2006.0066

  140. 140.

    Medrano-Galarza C. Gibbons J. Wagner S. de Passillé A. M. Rushen J. (2012 ). Behavioral changes in dairy cows with mastitis. J. Dairy Sci. 95 6994–7002.

    Not in our library10.3168/jds.2011-5247

  141. 141.

    Mehrzad J. Desrosiers C. Lauzon K. Robitaille G. Zhao X. Lacasse P. (2005 ). Proteases involved in mammary tissue damage during endotoxin-lnduced mastitis in dairy cows. J. Dairy Sci. 88 211–222.

    Not in our library10.3168/jds.s0022-0302(05)72679-5

  142. 142.

    Mehrzad J. Duchateau L. Burvenich C. (2004 ). Viability of milk neutrophils and severity of bovine coliform mastitis. J. Dairy Sci. 87 4150–4162.

    Not in our library10.3168/jds.s0022-0302(04)73558-4

  143. 143.

    Melchior M. B. Vaarkamp H. Fink-Gremmels J. (2006 ). Biofilms: a role in recurrent mastitis infections? Vet. J. 171 398–407.

    Not in our library10.1016/j.tvjl.2005.01.006

  144. 144.

    Mellata M. (2013 ). Human and avian extraintestinal pathogenic Escherichia coli: infections, zoonotic risks, and antibiotic resistance trends. Foodborne Pathog. Dis. 10 916–922.

    Not in our library10.1089/fpd.2013.1533

  145. 145.

    Méric G. Hitchings M. D. Pascoe B. Sheppard S. K. (2016 ). From Escherichia to the Escherichia coli genome. Lancet Infect. Dis. 16 634–636.

    Not in our library10.1016/s1473-3099(16)30066-4

  146. 146.

    Mitterhuemer S. Petzl W. Krebs S. Mehne D. Klanner A. Wolf E. (2010 ). Escherichia coli infection induces distinct local and systemic transcriptome responses in the mammary gland. BMC Genom. 11:138.

    Not in our library10.1186/1471-2164-11-138

  147. 147.

    Mohammed A. N. Radi A. M. Khaled R. Abo El-Ela F. I. Kotp A. A. (2020 ). Exploitation of new approach to control of environmental pathogenic bacteria causing bovine clinical mastitis using novel anti-biofilm nanocomposite. Environ. Sci. Pollut. Res. 27 42791–42805.

    Not in our library10.1007/s11356-020-10054-1

  148. 148.

    Momtaz H. (2010 ). Investigation of virulence factors in Escherichia coli isolated from clinical and subclinical bovine mastitis. Bulg. J. Vet. Med. 13 122–126.

    Not in our library

  149. 149.

    Momtaz H. Safarpoor Dehkordi F. Taktaz T. Rezvani A. Yarali S. (2012 ). Shiga toxin-producing Escherichia coli isolated from bovine mastitic milk: serogroups, virulence factors, and antibiotic resistance properties. Sci. World J. 2012:618709.

    Not in our library10.1100/2012/618709

  150. 150.

    Ngaywa C. Aboge G. O. Obiero G. Omwenga I. Ngwili N. Wamwere G. (2019 ). Antimicrobial resistant Escherichia coli isolates detected in raw milk of livestock in pastoral areas of northern Kenya. Food Control 102 173–178.

    Not in our library10.1016/j.foodcont.2019.03.008

  151. 151.

    Oliveira L. Ruegg P. L. (2014 ). Treatments of clinical mastitis occurring in cows on 51 large dairy herds in Wisconsin. J. Dairy Sci. 97 5426–5436.

    Not in our library10.3168/jds.2013-7756

  152. 152.

    Oliveira L. Hulland C. Ruegg P. L. (2013 ). Characterization of clinical mastitis occurring in cows on 50 large dairy herds in Wisconsin. J. Dairy Sci. 96 7538–7549.

    Not in our library10.3168/jds.2012-6078

  153. 153.

    Olson M. A. Siebach T. W. Griffitts J. S. Wilson E. Erickson D. L. Pinheiro J. O. O. (2018 ). Genome-wide identification of fitness factors in mastitis-associated Escherichia coli. Appl. Environ. Microbiol. 84:e02190-17.

    Not in our library10.1128/aem.02190-17

  154. 154.

    Olson M. E. Ceri H. Morck D. W. Buret A. G. Read R. R. (2002 ). Biofilm bacteria: formation and comparative susceptibility to antibiotics. Can. J. Vet. Res. 66 86–92.

    Not in our library

  155. 155.

    Ombarak R. A. Hinenoya A. Elbagory A. R. M. Yamasaki S. (2018 ). Prevalence and molecular characterization of antimicrobial resistance in Escherichia coli isolated from raw milk and raw milk cheese in Egypt. J. Food Prot. 81 226–232.

    Not in our library10.4315/0362-028x.jfp-17-277

  156. 156.

    Opijnen T. Bodi K. L. Camilli A. (2009 ). Tn-seq: high-throughput parallel sequencing for fitness and genetic interaction studies in microorganisms. Nat. Methods 6 767–772.

    Not in our library10.1038/nmeth.1377

  157. 157.

    Paape M. Bannerman D. Zhao X. Lee J. (2003 ). The bovine neutrophil: structure and function in blood and milk. Vet. Res. 34 597–627.

    Not in our library10.1051/vetres:2003024

  158. 158.

    Padmini N. Ajilda A. A. K. Sivakumar N. Selvakumar G. (2017 ). Extended spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae: critical tools for antibiotic resistance pattern. J. Basic Microbiol. 57 460–470.

    Not in our library10.1002/jobm.201700008

  159. 159.

    Panda B. S. K. Mohapatra S. K. Alhussien M. N. Dang A. K. (2019 ). Amount of milk neutrophil percentage and associated CD molecular changes on the compositional and technological properties of milk. Open Biotechnol. J. 13 129–136.

    Not in our library10.2174/187407070190130129

  160. 160.

    Passey S. Bradley A. Mellor H. (2008 ). Escherichia coli isolated from bovine mastitis invade mammary cells by a modified endocytic pathway. Vet. Microbiol. 130 151–164.

    Not in our library10.1016/j.vetmic.2008.01.003

  161. 161.

    Pedersen R. R. Krömker V. Bjarnsholt T. Dahl-Pedersen K. Buhl R. Jørgensen E. (2021 ). Biofilm research in bovine mastitis. Front. Vet. Sci. 8:656810.

    Not in our library10.3389/fvets.2021.656810

  162. 162.

    Peek C. T. Ibberson C. B. Cassat J. E. (2020 ). “Identification of virulence determinants during host-pathogen interaction using Tn-Seq technology’,” in Methicillin-Resistant Staphylococcus Aureus (MRSA) Protocols-Methods in Molecular Biology, ed. Ji Y. (New York, NY: Humana), 155–175.

    Not in our library10.1007/978-1-4939-9849-4_12

  163. 163.

    Persson Y. Katholm J. Landin H. Mörk M. J. (2015 ). Efficacy of enrofloxacin for the treatment of acute clinical mastitis caused by Escherichia coli in dairy cows. Vet. Rec. 176:673.

    Not in our library10.1136/vr.102667

  164. 164.

    Petzl W. Zerbe H. Günther J. Seyfert H. M. Hussen J. Schuberth H. J. (2018 ). Pathogen-specific responses in the bovine udder. Models and immunoprophylactic concepts. Res. Vet. Sci. 116 55–61.

    Not in our library10.1016/j.rvsc.2017.12.012

  165. 165.
  166. 166.

    Pomeroy B. Gurjar A. Sipka A. Klaessig S. Salmon S. Quesnell R. (2016 ). Intramammary immunization with ultraviolet-killed Escherichia coli shows partial protection against late gestation intramammary challenge with a homologous strain. J. Dairy Sci. 99 9014–9026.

    Not in our library10.3168/jds.2016-11149

  167. 167.
  168. 168.

    Radostitis O. Gay C. Hinchcliff K. Constable P. (2007 ). Veterinary Medicine: A Textbook of the Diseases of Cattle, Sheep, Pigs, Goats and Horses. Philadelphia: Saunders, 2180.

    Not in our library

  169. 169.

    Rainard P. Riollet C. (2006 ). Innate immunity of the bovine mammary gland. Vet. Res. 37 369–400.

    Not in our library10.1051/vetres:2006007

  170. 170.

    Rainard P. Gilbert F. B. Germon P. Foucras G. (2021a ).. Invited review: a critical appraisal of mastitis vaccines for dairy cows. J. Dairy Sci. 104 10427–10448.

    Not in our library10.3168/jds.2021-20434

  171. 171.

    Rainard P. Gilbert F. B. Martins R. P. Germon P. Foucras G. (2022 ). Progress towards the elusive mastitis vaccines. Vaccines 10 1–24.

    Not in our library10.3390/vaccines10020296

  172. 172.

    Rainard P. Repérant-Ferter M. Gitton C. Germon P. (2021b ). Shielding effect of Escherichia coli O-antigen polysaccharide on J5-induced cross-reactive antibodies. mSphere 6:e1227–e1220.

    Not in our library10.1128/msphere.01227-20

  173. 173.

    Rainard P. Répérant-Ferter M. Gitton C. Gilbert F. B. Germon P. (2017 ). Cellular and humoral immune response to recombinant Escherichia coli OmpA in cows. PLoS One 12:e0187369.

    Not in our library10.1371/journal.pone.0187369

  174. 174.

    Richards V. P. Lefébure T. Bitar P. D. P. Dogan B. Simpson K. W. Schukken Y. H. (2015 ). Genome based phylogeny and comparative genomic analysis of intra-mammary pathogenic Escherichia coli. PLoS One 10:e0119799.

    Not in our library10.1371/journal.pone.0119799

  175. 175.

    Rinaldi M. Li R. W. Bannerman D. D. Daniels K. M. Evock-Clover C. Silva M. V. B. (2010 ). A sentinel function for teat tissues in dairy cows: dominant innate immune response elements define early response to E. coli mastitis. Funct. Integr. Genom. 10 21–38.

    Not in our library10.1007/s10142-009-0133-z

  176. 176.

    Rocha L. S. Silva D. M. Silva M. P. Vidigal P. M. P. Silva J. C. F. Guerra S. T. (2019 ). Comparative genomics of Staphylococcus aureus associated with subclinical and clinical bovine mastitis. PLoS One 14:e0220804.

    Not in our library10.1371/journal.pone.0220804

  177. 177.

    Rollin E. Dhuyvetter K. C. Overton M. W. (2015 ). The cost of clinical mastitis in the first 30 days of lactation: an economic modeling tool. Prev. Vet. Med. 122 257–264.

    Not in our library10.1016/j.prevetmed.2015.11.006

  178. 178.

    Romero J. Benavides E. Meza C. (2018 ). Assessing financial impacts of subclinical mastitis on Colombian dairy farms. Front. Vet. Sci 5:273.

    Not in our library10.3389/fvets.2018.00273

  179. 179.

    Roussel P. Cunha P. Porcherie A. Petzl W. Gilbert F. B. Riollet C. (2015 ). Investigating the contribution of IL-17A and IL-17F to the host response during Escherichia coli mastitis. Vet. Res. 46:56.

    Not in our library10.1186/s13567-015-0201-4

  180. 180.
  181. 181.

    Royster E. Godden S. Goulart D. Dahlke A. Rapnicki P. Timmerman J. (2014 ). Evaluation of the Minnesota Easy Culture System II Bi-Plate and Tri-Plate for identification of common mastitis pathogens in milk. J. Dairy Sci. 97 3648–3659.

    Not in our library10.3168/jds.2013-7748

  182. 182.

    Rudenko P. Sachivkina N. Vatnikov Y. Shabunin S. Engashev S. Kontsevaya S. (2021 ). Role of microorganisms isolated from cows with mastitis in Moscow region in biofilm formation. Vet. World 14 40–48.

    Not in our library10.14202/vetworld.2021.40-48

  183. 183.

    Ruegg P. L. (2017 ). A 100-Year Review: mastitis detection, management, and prevention. J. Dairy Sci. 100 10381–10397.

    Not in our library10.3168/jds.2017-13023

  184. 184.

    Ruegg P. L. (2018 ). Making antibiotic treatment decisions for clinical mastitis. Vet. Clin. N. Am. - Food Anim. Pr. 34 413–425.

    Not in our library10.1016/j.cvfa.2018.06.002

  185. 185.

    Rybarczyk J. Kieckens E. Vanrompay D. Cox E. (2017 ). In vitro and in vivo studies on the antimicrobial effect of lactoferrin against Escherichia coli O157:H7. Vet. Microbiol. 202 23–28.

    Not in our library10.1016/j.vetmic.2016.05.010

  186. 186.

    Salamon H. Nissim-Eliraz E. Ardronai O. Nissan I. Shpigel N. Y. (2020 ). The role of O-polysaccharide chain and complement resistance of Escherichia coli in mammary virulence. Vet. Res. 51:77.

    Not in our library10.1186/s13567-020-00804-x

  187. 187.

    Schmid A. Hörmansdorfer S. Messelhäusser U. Käsbohrer A. Sauter-Louis C. Mansfeld R. (2013 ). Prevalence of extended-spectrum β-lactamase-producing Escherichia coli on Bavarian dairy and beef cattle farms. Appl. Environ. Microbiol. 79 3027–3032.

    Not in our library10.1128/aem.00204-13

  188. 188.

    Schukken Y. Chuff M. Moroni P. Gurjar A. Santisteban C. Welcome F. (2012 ). The “other” gram-negative bacteria in aastitis: Klebsiella, Serratia, and more. Vet. Clin. North Am. Food Anim. Pract. 28 239–256.

    Not in our library10.1016/j.cvfa.2012.04.001

  189. 189.

    Schukken Y. H. Günther J. Fitzpatrick J. Fontaine M. C. Goetze L. Holst O. (2011 ). Host-response patterns of intramammary infections in dairy cows. Vet. Immunol. Immunopathol. 144 270–289.

    Not in our library10.1016/j.vetimm.2011.08.022

  190. 190.

    Seegers H. Fourichon C. Beaudeau F. (2003 ). Production effects related to mastitis and mastitis economics in dairy cattle herds. Vet. Res. 34 475–491.

    Not in our library10.1051/vetres:2003027

  191. 191.

    Sepúlveda-Varas P. Proudfoot K. L. Weary D. M. von Keyserlingk M. A. G. (2016 ). Changes in behaviour of dairy cows with clinical mastitis. Appl. Anim. Behav. Sci. 175 8–13.

    Not in our library10.1016/j.applanim.2014.09.022

  192. 192.

    Shaheen T. Bilal Ahmad S. Rehman M. U. Muzamil S. Razak Bhat R. Hussain I. (2020 ). Investigations on cytokines and proteins in lactating cows with and without naturally occurring mastitis. J. King Saud. Univ. Sci. 32 2863–2867.

    Not in our library10.1016/j.jksus.2020.07.009

  193. 193.

    Sharifi S. Pakdel A. Ebrahimi M. Reecy J. M. Farsani S. F. Ebrahimie E. (2018 ). Integration of machine learning and metaanalysis identifies the transcriptomic bio-signature of mastitis disease in cattle. PLoS One 13:e0191227.

    Not in our library10.1371/journal.pone.0191227

  194. 194.

    Shimazaki K. I. Kawai K. (2017 ). Advances in lactoferrin research concerning bovine mastitis. Biochem. Cell Biol. 95 69–75.

    Not in our library10.1139/bcb-2016-0044

  195. 195.

    Shpigel N. Y. Elazar S. Rosenshine I. (2008 ). Mammary pathogenic Escherichia coli. Curr. Opin. Microbiol. 11 60–65.

    Not in our library10.1016/j.mib.2008.01.004

  196. 196.

    Singh K. Chandra M. Kaur G. Narang D. Gupta D. K. (2018 ). Prevalence and antibiotic resistance pattern among the mastitis causing microorganisms. Open J. Vet. Med. 8 54–64.

    Not in our library10.4236/ojvm.2018.84007

  197. 197.

    Sintes G. F. Bruckmaier R. M. Wellnitz O. (2020 ). Nonsteroidal anti-inflammatory drugs affect the mammary epithelial barrier during inflammation. J. Dairy Sci. 103 10742–10753.

    Not in our library10.3168/jds.2020-18818

  198. 198.

    Skarbye A. P. Krogh M. A. Sørensen J. T. (2018 ). The effect of individual quarter dry-off in management of subclinical mastitis on udder condition and milk production in organic dairy herds: a randomized field trial. J. Dairy Sci. 101 11186–11198.

    Not in our library10.3168/jds.2018-14794

  199. 199.

    Skočková A. Bogdanovičová K. Koláčková I. Karpíšková R. (2015 ). Antimicrobial-resistant and extended-spectrum β-lactamase-producing Escherichia coli in raw cow’s milk. J. Food Prot. 78 72–77.

    Not in our library10.4315/0362-028x.jfp-14-250

  200. 200.

    Sladek Z. Rysanek D. Ryznarova H. Faldyna M. (2005 ). Neutrophil apoptosis during experimentally induced Staphylococcus aureus mastitis. Vet. Res. 36 629–643.

    Not in our library10.1051/vetres:2005023

  201. 201.

    Sordillo L. M. (2005 ). Factors affecting mammary gland immunity and mastitis susceptibility. Livest. Prod. Sci. 98 89–99.

    Not in our library10.1016/j.livprodsci.2005.10.017

  202. 202.

    Sordillo L. M. (2018 ). Mammary gland immunobiology and resistance to mastitis. Vet. Clin. N. Am. - Food Anim. Pr. 34 507–523.

    Not in our library10.1016/j.cvfa.2018.07.005

  203. 203.

    Sordillo L. M. Shafer-Weaver K. DeRosa D. (1997 ). Immunobiology of the mammary gland. J. Dairy Sci. 80 1851–1865.

    Not in our library10.3168/jds.s0022-0302(97)76121-6

  204. 204.

    Srinivasan V. Gillespie B. E. Lewis M. J. Nguyen L. T. Headrick S. I. Schukken Y. H. (2007 ). Phenotypic and genotypic antimicrobial resistance patterns of Escherichia coli isolated from dairy cows with mastitis. Vet. Microbiol. 124 319–328.

    Not in our library10.1016/j.vetmic.2007.04.040

  205. 205.

    Steele N. M. Swartz T. H. Enger K. M. Schramm H. Cockrum R. R. Lacy-Hulbert S. J. (2019 ). The effect of J5 bacterins on clinical, behavioral, and antibody response following an Escherichia coli intramammary challenge in dairy cows at peak lactation. J. Dairy Sci. 102 11233–11249.

    Not in our library10.3168/jds.2019-16549

  206. 206.

    Sugrue I. Tobin C. Ross R. P. Stanton C. Hill C. (2019 ). “Foodborne pathogens and zoonotic diseases’,” in Raw Milk - Balance Between Hazards and Benefits, eds Nero L. A. Carvalho A. F. (London, UK: Academic Press), 259–272.

    Not in our library

  207. 207.

    Sun M. Gao X. Zhao K. Ma J. Yao H. Pan Z. (2021 ). Insight into the virulence related secretion systems, fimbriae, and toxins in O2:K1 Escherichia coli isolated from bovine mastitis. Front. Vet. Sci. 8:622725.

    Not in our library10.3389/fvets.2021.622725

  208. 208.

    Suojala L. Kaartinen L. Pyörälä S. (2013 ). Treatment for bovine Escherichia coli mastitis - An evidence-based approach. J. Vet. Pharmacol. Ther. 36 521–531.

    Not in our library10.1111/jvp.12057

  209. 209.

    Suojala L. Pohjanvirta T. Simojoki H. Myllyniemi A. L. Pitkälä A. Pelkonen S. (2011 ). Phylogeny, virulence factors and antimicrobial susceptibility of Escherichia coli isolated in clinical bovine mastitis. Vet. Microbiol. 147 383–388.

    Not in our library10.1016/j.vetmic.2010.07.011

  210. 210.

    Suojala L. Simojoki H. Mustonen K. Kaartinen L. Pyörälä S. (2010 ). Efficacy of enrofloxacin in the treatment of naturally occurring acute clinical Escherichia coli mastitis. J. Dairy Sci. 93 1960–1969.

    Not in our library10.3168/jds.2009-2462

  211. 211.

    Swain D. K. Kushwah M. S. Kaur M. Patbandha T. K. Mohanty A. K. Dang A. K. (2014 ). Formation of NET, phagocytic activity, surface architecture, apoptosis and expression of toll like receptors 2 and 4 (TLR2 and TLR4) in neutrophils of mastitic cows. Vet. Res. Commun. 38 209–219.

    Not in our library10.1007/s11259-014-9606-1

  212. 212.

    Swinkels J. M. Leach K. A. Breen J. E. Payne B. White V. Green (2021 ). Randomized controlled field trial comparing quarter and cow level selective dry cow treatment using the California Mastitis Test. J. Dairy Sci. 104 9063–9081.

    Not in our library10.3168/jds.2020-19258

  213. 213.
  214. 214.

    Taniguchi T. Latt K. M. Tarigan E. Yano F. Sato H. Minamino T. (2021 ). A 1-year investigation of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolated from bovine mastitis at a large-scale dairy farm in Japan. Microb. Drug Resist. 27 1450–1454.

    Not in our library10.1089/mdr.2020.0481

  215. 215.

    Tanih N. F. Sekwadi E. Ndip R. N. Bessong P. O. (2015 ). Detection of pathogenic Escherichia coli and Staphylococcus aureus from cattle and pigs slaughtered in abattoirs in Vhembe District. South Africa. Sci. World J. 2015:195972.

    Not in our library10.1155/2015/195972

  216. 216.

    Taponen S. Salmikivi L. Simojoki H. Koskinen M. T. Pyörälä S. (2009 ). Real-time polymerase chain reaction-based identification of bacteria in milk samples from bovine clinical mastitis with no growth in conventional culturing. J. Dairy Sci. 92 2610–2617.

    Not in our library10.3168/jds.2008-1729

  217. 217.

    Tenaillon O. Skurnik D. Picard B. Denamur E. (2010 ). The population genetics of commensal Escherichia coli. Nat. Rev. Microbiol. 8 207–217.

    Not in our library10.1038/nrmicro2298

  218. 218.
  219. 219.

    Tian L. Choi S. C. Lee H. N. Murakami Y. Qi C. F. Sengottuvelu M. (2016 ). Enhanced efferocytosis by dendritic cells underlies memory T-cell expansion and susceptibility to autoimmune disease in CD300f-deficient mice. Cell Death. Differ. 23 1086–1096.

    Not in our library10.1038/cdd.2015.161

  220. 220.

    Todorović D. Velhner M. Grego E. Vidanović D. Milanov D. Krnjaić D. (2018 ). Molecular characterization of multidrug-resistant Escherichia coli isolates from bovine clinical mastitis and pigs in the Vojvodina province. Serbia. Microb. Drug Resist. 24 95–103.

    Not in our library10.1089/mdr.2017.0016

  221. 221.

    Tomazi T. Gonçalves J. L. Barreiro J. R. Arcari M. A. dos Santos M. V. (2015 ). Bovine subclinical intramammary infection caused by coagulase-negative staphylococci increases somatic cell count but has no effect on milk yield or composition. J. Dairy Sci. 98 3071–3078.

    Not in our library10.3168/jds.2014-8466

  222. 222.

    Tong J. Zhang H. Zhang Y. Xiong B. Jiang L. (2019 ). Microbiome and metabolome analyses of milk from dairy cows with subclinical Streptococcus agalactiae mastitis—Potential biomarkers. Front. Microbiol. 10:2547.

    Not in our library10.3389/fmicb.2019.02547

  223. 223.

    Tourret J. Denamur E. (2016 ). Population phylogenomics of extraintestinal pathogenic Escherichia coli. Microbiol. Spectr 4

    Not in our library10.1128/microbiolspec.uti-0010-2012

  224. 224.

    Usami A. Tanaka M. Yoshikawa Y. Watanabe K. Ohtsuka H. Orino K. (2011 ). Heme mediated binding of α-casein to ferritin: evidence for preferential α-casein binding to ferrous iron. BioMetals 24 1217–1224.

    Not in our library10.1007/s10534-011-9470-1

  225. 225.

    USDA. (2016 ). Dairy 2014, Milk Quality, Milking Procedures and Mastitis in the United States. Fort Collins, CO: USDA.

    Not in our library

  226. 226.

    van der Helm D. (1998 ). The physical chemistry of bacterial outer-membrane siderophore receptor proteins. Met. Ions Biol. Syst. 35:355.

    Not in our library

  227. 227.

    Vitenberga-verza Z. Melderis I. Gontar Ł (2022 ). Identification of inflammatory and regulatory cytokines IL-1α-, IL- 4-, IL- 6-, IL- 12-, IL- 13-, IL- 17A-, TNF-α-, and IFN-γ-producing cells in the milk of dairy cows with subclinical and clinical mastitis. Pathogens 11 1–23.

    Not in our library10.3390/pathogens11030372

  228. 228.

    Wellnitz O. Bruckmaier R. M. (2012 ). The innate immune response of the bovine mammary gland to bacterial infection. Vet. J. 192 148–152.

    Not in our library10.1016/j.tvjl.2011.09.013

  229. 229.

    Wente N. Grieger A. S. Klocke D. Paduch J. H. Zhang Y. Leimbach S. (2020 ). Recurrent mastitis–persistent or new infections? Vet. Microbiol. 244:108682.

    Not in our library10.1016/j.vetmic.2020.108682

  230. 230.

    Wenz J. R. Barrington G. M. Garry F. B. Ellis R. P. Magnuson R. J. (2006 ). Escherichia coli isolates’ serotypes, genotypes, and virulence genes and clinical coliform mastitis severity. J. Dairy Sci. 89 3408–3412.

    Not in our library10.3168/jds.s0022-0302(06)72377-3

  231. 231.
  232. 232.

    Westermann A. J. Förstner K. U. Amman F. Barquist L. Chao Y. Schulte L. N. (2016 ). Dual RNA-seq unveils noncoding RNA functions in host-pathogen interactions. Nature 529 496–501.

    Not in our library10.1038/nature16547

  233. 233.

    White L. J. Schukken Y. H. Dogan B. Green L. Döpfer D. Chappell M. J. (2010 ). Modelling the dynamics of intramammary E. coli infections in dairy cows: understanding mechanisms that distinguish transient from persistent infections. Vet. Res. 41:13.

    Not in our library10.1051/vetres/2009061

  234. 234.

    Wilson D. J. Mallard B. A. Burton J. L. Schukken Y. H. Grohn Y. T. (2009 ). Association of Escherichia coli J5-specific serum antibody responses with clinical mastitis outcome for J5 vaccinate and control dairy cattle. Clin. Vaccine Immunol. 16 209–217.

    Not in our library10.1128/cvi.00324-08

  235. 235.

    Yang F. Zhang S. Shang X. Wang X. Wang L. Yan Z. (2018 ). Prevalence and characteristics of extended spectrum β-lactamase-producing Escherichia coli from bovine mastitis cases in China. J. Integr. Agric. 17 1246–1251.

    Not in our library10.1016/s2095-3119(17)61830-6

  236. 236.
  237. 237.

    Zaatout N. (2022 ). An overview on mastitis-associated Escherichia coli: pathogenicity, host immunity and the use of alternative therapies. Microbiol. Res. 256:126960.

    Not in our library10.1016/j.micres.2021.126960

  238. 238.

    Zadoks R. N. Middleton J. R. McDougall S. Katholm J. Schukken Y. H. (2011 ). Molecular epidemiology of mastitis pathogens of dairy cattle and comparative relevance to humans. J. Mammary Gland Biol. Neoplasia 16 357–372.

    Not in our library10.1007/s10911-011-9236-y

  239. 239.

    Zhang D. Zhang Z. Huang C. Gao X. Wang Z. Liu Y. (2018 ). The phylogenetic group, antimicrobial susceptibility, and virulence genes of Escherichia coli from clinical bovine mastitis. J. Dairy Sci. 101 572–580.

    Not in our library10.3168/jds.2017-13159

  240. 240.

    Zhang H. Jiang H. Fan Y. Chen Z. Li M. Mao Y. (2018 ). Transcriptomics and iTRAQ-proteomics analyses of bovine mammary tissue with Streptococcus agalactiae-induced mastitis. J. Agric. Food Chem. 66 11188–11196.

    Not in our library10.1021/acs.jafc.8b02386

  241. 241.

    Zhang J. Xu C. Huo D. Hu Q. Peng Q. (2017 ). Comparative study of the gut microbiome potentially related to milk protein in Murrah buffaloes (Bubalus bubalis) and Chinese Holstein cattle. Sci. Rep 7:42189.

    Not in our library10.1038/srep42189

  242. 242.

    Zhang S. Abbas M. Rehman M. U. Huang Y. Zhou R. Gong S. (2020 ). Dissemination of antibiotic resistance genes (ARGs) via integrons in Escherichia coli: a risk to human health. Environ. Pollut. 266:115260.

    Not in our library10.1016/j.envpol.2020.115260

  243. 243.

    Zhao X. Lacasse P. (2008 ). Mammary tissue damage during bovine mastitis: causes and control. J. Anim. Sci. 86 57–65.

    Not in our library10.2527/jas.2007-0302

  244. 244.

    Zhou M. Yang Y. Wu M. Ma F. Xu Y. Deng B. (2021 ). Role of long polar fimbriae type 1 and 2 in pathogenesis of mammary pathogenic Escherichia coli. J. Dairy Sci. 104 8243–8255.

    Not in our library10.3168/jds.2021-20122

  245. 245.

    Zigo F. Vasil’ M. Ondrašovičová S. Výrostková J. Bujok J. Pecka-Kielb E. (2021 ). Maintaining optimal mammary gland health and prevention of mastitis. Front. Vet. Sci. 8 607311.

    Not in our library10.3389/fvets.2021.607311

Cited by papers we hold 1

Reads

Read by people on this page

None yet.

Checked or read by AI through naulon

None yet.

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.

Are you an author?

Is this your paper?

Claim it to add your note and be paid when agents cite it. Free.