TABLE 1 - uploaded by Graham F Medley
Content may be subject to copyright.
Sequence types detected in cows and quarters over time Cow no. Quarter ST recovered at visit no. a :
Source publication
An outbreak of Staphylococcus aureus intramammary infections on an organic dairy farm was monitored for 10 months. Environmental and milk samples were collected
from a total of 26 cows and a group of 21 purchased heifers about to be introduced into the milking herd. There was variation
in the rate of isolation of S. aureus (9.5 to 43.8%) from indiv...
Context in source publication
Similar publications
![FIGURE 5 | GrapeTree of Salmonella serovar I 4,[5],12:i:-and...](publication/354635565/figure/fig4/AS:1068761943654400@1631824112495/GrapeTree-of-Salmonella-serovar-I-4-5-12i-and-Typhimurium-isolates-GrapeTree-of_Q320.jpg)
Salmonella enterica ( S. enterica ) is an important foodborne pathogen, causing food poisoning and human infection, and critically threatening food safety and public health. Salmonella typing is essential for bacterial identification, tracing, epidemiological investigation, and monitoring. Serotyping and multilocus sequence typing (MLST) analysis a...
Beta-hemolytic group C and G streptococci cause a considerable invasive disease burden and sometimes cause disease outbreaks. Little is known about the critical epidemiologic parameter of genetic relatedness between isolates. We determined the emm types of 334 Streptococcus dysgalactiae subsp. equisimilis isolates, and attempted emm typing of 5 Str...
Ninety-six methicillin-resistant Staphylococcus aureus (MRSA) isolates from eight Korean hospitals were analyzed by multilocus sequence typing, SCCmec typing, and spa typing. The predominant genotype was ST5-MRSA-II of clonal complex 5, which was found in 36 isolates from six hospitals,
but ST239-MRSA-III was also common. Overall, results showed a...
The BD GeneOhm methicillin-resistant Staphylococcus aureus (MRSA) assay is a molecular screening test for detection of MRSA in nasal colonization. This assay coamplifies the extremity
of staphylococcal chromosome cassette mec (SCCmec) and adjacent chromosomal DNA at the SCCmec insertion site. Increasing reports of novel SCCmec types and the diverse...
Three Gram-stain positive, non-motile, non-spore-forming, catalase-negative and rod-shaped bacterial strains (IWT5T, IWT25T and IWT140), isolated from silage, were investigated by using a polyphasic taxonomic approach. Strains IWT5T and IWT25T grew at 10-37 °C and 30-37 °C, and at pH 4.0-7.5 and 4.0-7.0, respectively. The G+C contents of genomic DN...
Citations
... The results observed on S. aureus pulsotypes indicate a low genetic diversity among the isolates, which can be explained by the proximity of the herds. Smith and Green [21] emphasized that the detection of clonal profiles in a herd that differ from those commonly isolated may be the result of selection pressure and these profiles are specific for a certain geographic region (Midwest area of São Paulo State, Brazil). ...
... In this current study, all strains of S. aureus were considered susceptible to methicillin since neither mecA nor mecC were detected when previous molecular analyses were performed (data not shown). It is possible, therefore, that a dominant clonal pattern may be more pathogenic, being easily spread out within the herd, even under good milking conditions [21]. Thus, knowledge of the epidemiology of S. aureus, as obtained by molecular typing herein, contributes to the development of strategies for the control and prevention of persistent S. aureus causing IMI. ...
The study aimed to evaluate the genetic diversity of Staphylococcus aureus causing subclinical mastitis (SM) isolated from dairy cows and to assess the effect of the infection status (transient vs. persistent) on the milk and component yield. A total of six dairy farms in São Paulo state were used for the selection of cows with SM caused by S. aureus. S. aureus strains (n = 56) obtained from three biweekly aseptic mammary quarter milk samplings (n = 1140 from 95 cows) were subjected to MALDI-TOF MS analysis for species confirmation and further PFGE analysis. Intramammary infections (IMI) caused by S. aureus were categorized as transient (T: when only one out of 3 milk samplings had positive isolation of any pulsotype) or persistent (P: when two (P2) or three (P3) milk samplings had positive isolation of identical pulsotype over the consecutive episodes of SM. The SmaI macrorestriction fragment profiles of 56 S. aureus isolates showed a dominant S. aureus clonal pattern (PFGE type A; n = 50; 89.3%) within and among the herds. The SM-causing S. aureus represented a reduction of quarter milk yield of 26.2% in transient and 54.8% in persistent cases as well as a reduction of total solid yield of 38.1% and 49.4%, respectively, when compared with the healthy control quarters. Overall, the greater chance of S. aureus to be persistent is when a dominant clonal pattern is present in the herd which consequently may be associated with the cause of accentuated milk loss.
... This is in line with the fact that Staphylococcus spp. was a common cause of SCM as revealed in this study. Staphylococci generally cause chronic infections (Sağlam et al. 2017) and, even during a dry period, a substantial proportion of these cases are never cured (Smith et al. 2005). Therefore, the older cows likely accumulate more intramammary infections (IMI) than younger animals, resulting in a higher prevalence of SCM. ...
Mastitis is a major production disease, causing significant economic losses for dairy farmers in South-Asian countries, as well as other parts of the world. Udder health control programs (UHCP) have been established in developed countries as an effective strategy for mastitis control but have not yet been introduced in South-Asian low-income countries like Bangladesh, India, Pakistan, and Sri Lanka. To launch UHCP successfully in dairy herds in South-Asia, it is important to know the current prevalence and risk factors for subclinical mastitis (SCM). Therefore, a narrative literature review was conducted with the aim to describe the dairy sector, the prevalence of SCM and its causal agents, risk factors for mastitis occurrence and the control measures suggested by different studies conducted in the selected countries. The literature revealed that India had the highest cattle population. Milking was mainly done by hand in all of the studied countries. Stall feeding was done in Bangladesh and Sri Lanka and limited access to grazing was also reported in some farms in India and Pakistan. There was substantial variation in the prevalence of SCM between studies in all 4 countries, ranging from about 20% to about 80%, but the average prevalence across all studies was high (50%). The most common causal agents for SCM were non-aureus staphylococci (NAS), Staphylococcus (S.) aureus, Streptococcus spp. and Escherichia (E.) coli. The management related risk factors reported for SCM were stall feeding of cows, a higher stock density, cracked floors, open drains, the presence of flies, poor drainage, peri-parturient diseases, infrequent dung removal and earth floors. The control measures suggested in these studies were to improve the hygiene and sanitation of cows, to improve the cleanliness of farms and milker’s hands, to apply dry cow therapy, supplementing micronutrients and routine screening for SCM combined with taking intervention measures like isolation of cows or milking infected cows last, and proper treatment. Also, full hand milking, complete milking, machine milking, and providing feed and water immediately after milking have been recommended. Finally, we show that current literature often studies the same set of (non-manageable) risk factors, so more research is needed to obtain a comprehensive picture of the determinants of SCM. Randomized controlled trials are needed to truly quantify the effect of intervention under field conditions. Altogether, our work gives an overview of the udder health situation in South-Asia and provides the basis for the design of UHCP in this region.
... with the software package BURST (Zhang et al., 2016). MLST has been widely used in genotyping for epidemiological (Ben Said et al., 2016;Boss et al., 2016;Budd et al., 2015;Cremonesi et al., 2015;Khemiri et al., 2018;Kwon et al., 2005;Li et al., 2017;McMillan et al., 2016;Rabello et al., 2007;Silva et al., 2014;Schmidt et al., 2017;Smith et al., 2005a;Smith et al., 2005b), and evolutionary studies of bovine MRSA (Aqib et al., 2018;Basanisi et al., 2017;Silva et al., 2014;Tavakol et al., 2012;Tegegne et al., 2019;Vanderhaeghen et al., 2010;Wang et al., 2015;Yi et al., 2018). MLST has been proven to be an excellent method for long-term global studies of S. aureus (Holmes and Zadoks, 2011). ...
... It is generally agreed that at present, MLST is the method that gives the most reliable information about the phylogenetic clustering of S. aureus isolates (Hasman et al., 2010). It also offers the advantages of being highly reproducible and typeable, making it an excellent tool for global comparisons of population structures (McMillan et al., 2016;Smith et al., 2005a;Smith et al., 2005b). It has been shown that MLST, which uses genetic variation that accumulates very slowly in seven housekeeping genes, has proven very useful for long-term macroepidemiology and evolutionary studies (Koreen et al., 2004;Stefani et al., 2012). ...
In cattle, Staphylococcus aureus is a major pathogen of increasing importance due to its association with intramammary infections (IMIs), which are a primary cause of antibiotic use on farms and thus of the rise in antibiotic resistance. Methicillin-resistant S. aureus (MRSA), which are frequently isolated from cases of bovine mastitis, represent a public health problem worldwide. Understanding the epidemiology and the evolution of these strains relies on typing methods. Such methods were phenotypic at first, but more recently, molecular methods have been increasingly utilized. Multiple-locus variable number tandem repeat analysis (MLVA), a high-throughput molecular method for determining genetic diversity and the emergence of host- or udder-adapted clones, appears to be the most useful PCR-based method. Despite the difficulties present in reproducibility, interlaboratory reliability, and hard work, it is agreed that pulsed-field gel electrophoresis (PFGE) remains the gold standard, particularly for short-term surveillance. Multilocus sequence typing (MLST) is a good typing method for long-term and global epidemiological investigations, but it is not suitable for outbreak investigations. Staphylococcal protein A (spa) typing is the most widely used method today for first-line typing in the study of molecular evolution, and outbreaks investigations. Staphylococcal cassette chromosome mec (SCCmec) typing has gained popularity for the evolutionary analysis of MRSA strains. Whole-genome sequencing (WGS) and DNA microarrays that represent relatively new DNA-based technologies, provide more information for tracking antibioresistant and virulent outbreak strains. They offer a higher discriminatory power, but are not suitable for routine use in clinical veterinary medicine at this time. Descriptions of the evolution of these methods, their advantages, and limitations are given in this review.
... Based on molecular evidence from intercontinental studies, the consensus is that although multiple Staph. aureus strains could coexist within dairy farms, only a reduced subset of these strains are often associated with IMI (Smith et al., 2005;Zadoks et al., 2011;Leuenberger et al., 2019). ...
Staphylococcus aureus is one of the most frequent pathogens causing intramammary infections in dairy herds. Consequently, virulence factors, pathobiology, and epidemiology of Staphylococcus aureus strains have been widely assessed through the years. Nevertheless, not much has been described about the epidemiology of Staph. aureus strains from bulk tank milk (BTM) and adherences on milking equipment (AMES), even when these strains may play a role in the quality of milk that is intended for human consumption. The objective of this study was to assess the strain diversity of 166 Staph. aureus isolates collected from 3 consecutive BTM samples, and from AMES in contact with milk from 23 Chilean dairy farms. Isolates were analyzed and typed using pulsed-field gel electrophoresis. Diversity of strains, both within and among farms, was assessed using Simpson's index of diversity (SID). On farms where Staph. aureus was isolated from both AMES and BTM (n = 8), pulsotypes were further analyzed to evaluate the role of AMES as a potential source of Staph. aureus strains in BTM. Among all Staph. aureus analyzed by pulsed-field gel electrophoresis, a total of 42 pulsotypes (19 main pulsotypes and 23 subtypes) were identified. Among dairy farms, strain diversity was highly heterogeneous (SID = 0.99). Within dairy farms, Staph. aureus strain diversity was variable (SID = 0 to 1), and 18 dairy operations (81.8%) had one pulsotype that was shared between at least 2 successive BTM samples. In those farms where Staph. aureus was isolated in both AMES and BTM (n = 8), 7 (87.5%) showed a clonal distribution of Staph. aureus strains between these 2 types of samples. The overlapping of certain Staph. aureus strains among dairy farms may point out common sources of Staph. aureus among otherwise epidemiologically unrelated farms. Indistinguishable Staph. aureus strains between AMES and BTM across dairy farms suggest that Staph. aureus–containing AMES may represent a source for BTM contamination, thus affecting milk quality. Our study highlights the role of viable Staph. aureus in AMES as a source for BTM contamination on dairy farms, and also describes the overlapping and presence of specific BTM and AMES pulsotypes among farms.
... Enterotoxins have been associated with staphylococcal food poisoning caused by cow milk or other dairy products (81)(82)(83). Interestingly, isolates from the highly prevalent CC97 and CC133 that are strongly associated with CM (52,58,84) had no enterotoxin genes. Exotoxin genes were prevalent in S. aureus isolates, and, except for the set15 gene, all other genes were detected in at least 1 isolate. ...
Staphylococcus aureus is a major cause of bovine intramammary infections, leading to significant economic losses to dairy industry in Canada and worldwide. There is a lack of knowledge regarding genetic diversity, the presence of antimicrobial resistance (AMR), and virulence genes for S. aureus isolated from bovine milk in Canada. Based on whole-genome sequencing and genomic analysis, we have determined the phylogeny and diversity of S. aureus in bovine milk and concluded that it had a large accessory genome, limited distribution of AMR genes, variable VF gene profiles and sequence types (ST), and clonal complex (CC)-specific pathogenic potentials. Comprehensive information on the population structure, as well as the virulence and resistance characteristics of S. aureus from bovine milk, will allow for source attribution, risk assessment, and improved therapeutic approaches in cattle.
... uberis isolated from cows affected by clinical and subclinical mastitis. We observed that Caat 1-54 and Caat P5-8 presented antimicrobial activity due to the active compounds lysolipin I (Drautz et al., 1975) and kalafungin (Kakinuma et al., 1990) (Smith et al., 2005;Costa et al., 2012). On the other hand, ceftiofur and Caat P5-8 extract presented higher concentrations than Caat 1-54 to inhibit Staph. ...
... In fact, as mentioned herein, this variability of MIC values for the inhibition of bacterial growth may be caused by the diversity of Staph. aureus strains (Smith et al., 2005;Costa et al., 2012). Furthermore, previous results suggest a bacterial growth inhibition from plants to treat bovine mastitis (Ananda Baskaran et al., 2009). ...
Actinobacteria have been researched as a source that produces crude extracts, which contain bioactive compounds able to act as antimicrobial agents. The present investigation evaluated the dose-response effect of two crude extracts, obtained at Caatinga rhizosphere (Caat) and Rhizophora mangle (AMC), on in vitro ruminal fermentation by: cumulative gas production, digestibility of dry (IVDMD) and organic matter (IVOMD), and short-chain fatty acids concentration (SCFA). Three multiparous Holstein dairy cows with ruminal fistula were used as the inoculum donors and fed a basal diet consisting of corn silage, soybean meal, urea, ground corn and mineral supplement. Ruminal fluid samples were incubated in glass bottles with 1 g of the dried and milled diet, a buffer solution, and the crude extracts evaluated in four doses (0.3, 0.6, 0.9 and 1.20 mg/10 mL inoculum) in a randomized block design, and the donators were considered as blocks with random effects. Additionally, negative controls were used. The results were expressed as average values based on triplicate analyses. Decreased cumulative gas production was observed according to linear dose response at 24, 48 and 72 h of incubation with the addition of Caat extract. The IVOMD showed a linear decrease at 72 h of incubation with dose Caat inclusion. Furthermore, the inclusion of Caat extract linearly reduced butyric and isovaleric acid concentrations, as well as acetate:propionate ratio. Finally, the Caat inclusion increased the propionic acid concentration in comparison to AMC extract. However, the inclusion of AMC extract did not affect any of the analyzed variables at the used doses. The Caat extract could be used as a modulator of in vitro ruminal fermentation, since it reduced acetate:propionate ratio and cumulative gas production.
... However, Mørk et al. 37 observed that common genotypes caused mastitis in cows, goats and dairy sheep, suggesting specificity of anatomical sites rather than host specificity. The distribution of S. aureus clones associated with human infections [38][39][40][41] and with bovine mastitis 42,43 has been characterized and investigated using molecular techniques such as multilocus sequence typing (MLST). Important clonal complexes (CCs) associated with infections by S. aureus in human beings (CC1, CC5 and CC30) were also found in isolates from dairy cattle in geographically distinct herds 23 . ...
... Important clonal complexes (CCs) associated with infections by S. aureus in human beings (CC1, CC5 and CC30) were also found in isolates from dairy cattle in geographically distinct herds 23 . These observations have suggested the possibility of the transmission of strains between humans and cattle/dairy products, as previously reported 42,43 . Further investigation demonstrated that those CCs (CC1, CC5 and CC30) were often isolated from asymptomatic carriers or patients with invasive disease 38,40,41 ; moreover, it has been suggested that the genetic background of these CCs allows greater capacity to spread among humans 40 . ...
Background
The genetic variability of 610 S. aureus isolates from the hands of professional dentists (A), dental clinic environment air (B), bovine milk from cows with and without mastitis (C), an insufflator for milking equipment (D) and milking environment air (E) was studied by isoenzyme genotyping and genetic and cluster analysis.
Results
Monoclonal and polyclonal patterns of S. aureus were detected in every bacterial population; however, isolates belonging to the same strain were not found among the populations, suggesting the genetic heterogeneity and the intrapopulation spread of strains. Genetic relationship analysis revealed the co-existence of highly related strains at low frequency among populations.
Conclusion
The data suggest that some strains can adapt and colonize new epidemiologically unrelated habitats. Consequently, the occurrence of an epidemiological genotypic identity can assume a dynamic character (spread to new habitats), however infrequently. A tendency of microevolutionary and genetic divergences among populations of S. aureus from human sources (AB) and bovine milk (DE), and especially the mammary quarter (C), is also suggested. This research can contribute to the knowledge on the distribution and dissemination of strains and the implementation of control measures and eradication of S. aureus in important dental clinic environments, as well as animal environments and dairy production.
... uberis isolated from cows affected by clinical and subclinical mastitis. We observed that Caat 1-54 and Caat P5-8 presented antimicrobial activity due to the active compounds lysolipin I (Drautz et al., 1975) and kalafungin (Kakinuma et al., 1990) (Smith et al., 2005;Costa et al., 2012). On the other hand, ceftiofur and Caat P5-8 Few studies have evaluated the antimicrobial activity of crude extracts produced by actinomycetes against mastitis pathogens. ...
... In fact, as mentioned herein, this variability of MIC values for the inhibition of bacterial growth may be caused by the diversity of Staph. aureus strains (Smith et al., 2005;Costa et al., 2012). Furthermore, previous results suggest a bacterial growth inhibition from plants to treat bovine mastitis (Ananda Baskaran et al., 2009). ...
The emergence of antimicrobial resistance to commonly used antibiotics has necessitated the development of new antimicrobial products. Crude extracts produced by actinomycetes contain antimicrobial metabolites that can inhibit bacterial growth. The objective of our study was to evaluate the antimicrobial activity of crude extracts (Caat1-54 and CaatP5-8) produced by actinomycetes against isolates of Staphylococcus aureus, Staphylococcus chromogenes, Streptococcus dysgalactiae, and Streptococcus uberis, which were obtained from the milk of cows affected by mastitis in 23 dairy herds. Twenty isolates of each bacterial species were used to define minimum inhibitory concentration (MIC) of both crude extracts and ceftiofur (positive control). The MIC50 and MIC90 were defined at the concentration required to inhibit the growth of 50 and 90% of bacterial isolates tested, respectively. The MIC results were evaluated by survival analysis. Staphylococcus aureus isolates presented MIC90 of Caat 1-54 ≥6.25 µg/mL, ceftiofur ≥12.5 µg/mL, and Caat P5-8 ≥100 µg/mL. Streptococcus uberis presented MIC90 of ceftiofur ≥0.39 µg/mL, Caat 1-54 ≥50 µg/mL, and Caat P5-8 ≥100 µg/mL. Staphylococcus chromogenes isolated from subclinical mastitis presented MIC90 of Caat 1-54 ≥0.78 µg/mL and ceftiofur and Caat P5-8 of ≥6.25 and ≥100 µg/mL, respectively. Streptococcus dysgalactiae isolated from clinical mastitis presented similar MIC90 values between antimicrobials tested (ceftiofur, Caat 1-54, and Caat P-58), but these values (≥100 µg/mL) were higher than the values obtained from other pathogens evaluated in the present study. Our results indicate that Caat 1-54 and Caat P5-8 crude extracts present in vitro antimicrobial activity against isolates of Staph. aureus, Staph. chromogenes, Strep. dysgalactiae, and Strep. uberis isolated from clinical and subclinical mastitis.
... S. aureus isolates collected from dairy cattle with mastitis have been studied by various molecular methods such as multi locus sequence typing (MLST), pulsed filed gel electrophoresis (PFGE), and agr cluster and spa typing, which allow for the characterization of this pathogen through the comparison of sequences or fragments described in different parts of the world; these techniques can also be used to trace, dispersal routes and demonstrate the global spread of clones [9,10]. Many studies have shown that only a few specialized clones are responsible for most cases of mastitis on a single farm and some of these clones may have a wide geographical distribution [9,11]. ...
... S. aureus isolates collected from dairy cattle with mastitis have been studied by various molecular methods such as multi locus sequence typing (MLST), pulsed filed gel electrophoresis (PFGE), and agr cluster and spa typing, which allow for the characterization of this pathogen through the comparison of sequences or fragments described in different parts of the world; these techniques can also be used to trace, dispersal routes and demonstrate the global spread of clones [9,10]. Many studies have shown that only a few specialized clones are responsible for most cases of mastitis on a single farm and some of these clones may have a wide geographical distribution [9,11]. ...
Bovine mastitis has been a concern for dairy herd for decades. The adaptation capacity of one of the main species responsible for this disease, Staphylococcus aureus (S. aureus), plays a pivotal role in this issue. The aim of this study was to establish a molecular and phenotypic profile of 285 S. aureus strains isolated from milk of subclinical mastitis cows from 18 different farms in São Paulo State using spa typing, multilocus sequence typing (MLST), pulsed field gel electrophoresis (PFGE), agr cluster (I, II, III and IV) typing, PCR for genes including enterotoxins (sea, seb, sec, sed, see, seg, seh, sei), toxic shock syndrome toxin (tsst-1), and Panton-Valentine leucocidin (pvl), as well as in vitro resistance assays for 12 antibiotics. The results showed a wide variety of strains with a high toxigenic potential; concomitantly, sec, seg and seh were prevalent. In addition, we observed a predominance of the spa types t605 (ST 126, CC126) and t127 (ST1, CC1) and the unusual presence of t321 causing bovine mastitis, which has been previously reported only in swine. The most frequent ST were ST126 (70.5%) and ST1 (10.5%). Regarding PFGE, we observed four major groups and six profile patterns. The highest resistance was observed for streptomycin (9.5%), followed by tetracycline (3.5%), clindamycin (9.3%), and erythromycin (2.8%). The tsst-1 gene was detected in 36.8% of isolates and pvl was not observed. One hundred and thirty-six (47.7%) isolates possessed agr type II, followed by types III (20%) and I (8.1%), with type IV not being detected. We observed that the same spa type could result in different PFGE profiles, so the exclusive use of spa type sequences can lead to incorrect interpretations regarding the spread of clones in an epidemiological context.
... E-ISSN 2286 of S. aureus in goats from North Tunisia) (Gharsa et al. 2015), and Rahimi et al. (25% in Iran) (Rahimi et al. 2015) and considerably lower than rates recorded in Norway (68.9%) (Mørk et al. 2010) and Denmark (64%) (Eriksson et al. 2013). On the other hand, previous reports have indicated a S. aureus nasal carriage rate of 6% in dairy goats (Valle et al. 1991) and a total absence of S. aureus in nasal swabs in dairy cows from Norway (Jørgensen et al. 2005) and the United Kingdom (Smith et al. 2005), despite a high frequency of S. aureus mastitis. These different carriage rates could at least partially be due to self-care behaviors such as nose licking in herd goats and/or different farm managements. ...
Coagulase positive Staphylococcus species are important opportunistic pathogens in most animals which could be considered as a potential source of infection and dissemination to the environment. Prevalence studies and accurate identification of Coagulase Positive Staphylococcus species are essential in veterinary microbiology. A total of 153 healthy goats from North and North West of Tunisia were screened for coagulase positive Staphylococcus species nasal and rectal carriage. Bacteriological tests were performed. Staphylococcus spp. was detected in 120 of 153 studied goats (77.4%) and an overall prevalence of 22.2% of coagulase positive Staphylococcus species isolates was observed. This study showed the identification of S. aureus and S. pseudintermedius in 25 and 7 strains, respectively.
