Identification of Streptococcus uberis Multilocus Sequence Types Highly Associated with Mastitis

ABSTRACT Multilocus sequence typing analysis of Streptococcus uberis has identified a cluster of isolates associated with clinical and subclinical mastitis and a cluster associated with cows with low somatic cell counts in their milk. Specific groups of genotypes (global clonal complex [GCC] sequence type 5s [ST5s] and GCC ST143s) were highly associated (P = 0.006) with clinical and subclinical mastitis and may represent a lineage of virulent isolates, whereas isolates belonging to GCC ST86 were associated with low-cell-count cows. This study has, for the first time, demonstrated the occurrence of identical sequence types (ST60 and ST184) between different continents (Australasia and Europe) and different countries (Australia and New Zealand). The standardized index of association and the empirical estimation of the rate of recombination showed substantial recombination within the S. uberis population in Australia, consistent with previous multilocus sequence type analyses.

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First Report of blaNDM-1 Bearing IncX3 Plasmid in Clinically Isolated ST11 Klebsiella pneumoniae from Pakistan

Microorganisms ◽

10.3390/microorganisms9050951 ◽

2021 ◽

Vol 9 (5) ◽

pp. 951

Author(s):

Hazrat Bilal ◽

Gaojian Zhang ◽

Tayyab Rehman ◽

Jianxion Han ◽

Sabir Khan ◽

...

Keyword(s):

Sequence Type ◽

The Other ◽

High Rate ◽

Antibiotics Resistance ◽

New Delhi ◽

Molecular Type ◽

Plasmid Analysis ◽

First Time ◽

Encoding Genes ◽

Sequence Types

The New Delhi Metallo-β-lactamase (NDM) is among the most threatening forms of carbapenemases produced by K. pneumoniae, well-known to cause severe worldwide infections. The molecular epidemiology of blaNDM-1-harboring K. pneumoniae is not well elucidated in Pakistan. Herein, we aim to determine the antibiotics-resistance profile, genes type, molecular type, and plasmid analysis of 125 clinically isolated K. pneumoniae strains from urine samples during July 2018 to January 2019 in Pakistan. A total of 34 (27.2%) K. pneumoniae isolates were carbapenemases producers, and 23 (18.4%) harbored the blaNDM-1 gene. The other carbapenemases encoding genes, i.e., blaIMP-1 (7.2%), blaVIM-1 (3.2%), and blaOXA-48 (2.4%) were also detected. The Multi Locus Sequence Typing (MLST) results revealed that all blaNDM-1-harboring isolates were ST11. The other sequence types detected were ST1, ST37, and ST105. The cluster analysis of Xbal Pulsed Field Gel Electrophoresis (PFGE) revealed variation amongst the clusters of the identical sequence type isolates. The blaNDM-1 gene in all of the isolates was located on a 45-kb IncX3 plasmid, successfully transconjugated. For the first time, blaNDM-1-bearing IncX3 plasmids were identified from Pakistan, and this might be a new primary vehicle for disseminating blaNDM-1 in Enterobacteriaceae as it has a high rate of transferability.

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Prevalence of coagulase-negative staphylococci in bovine mastitis in Zimbabwe

Journal of the South African Veterinary Association ◽

10.4102/jsava.v73i2.557 ◽

2002 ◽

Vol 73 (2) ◽

Cited By ~ 2

Author(s):

T. Kudinha ◽

C. Simango

Keyword(s):

Somatic Cell ◽

Enteric Bacteria ◽

Subclinical Mastitis ◽

Clinical Mastitis ◽

Bacillus Species ◽

Small Scale ◽

Coagulase Negative Staphylococci ◽

Somatic Cell Counts ◽

Milk Samples ◽

Cell Counts

This study was carried out to determine the prevalence of coagulase-negative staphylococci in clinical and subclinical mastitis in commercial and small-scale farms in Zimbabwe. Thirty five quarter milk samples from clinical mastitis cases and 371 quarter milk samples from cows with subclinical mastitis were cultured for bacterial pathogens. The most frequent pathogens isolated in clinical mastitis were the enteric bacteria (31.4 %), followed by coagulase negative staphylococci (22.9 %) and then Staphylococcus aureus (17.1 %), whereas in subclinical mastitis S. aureus (34.2 %) and coagulase-negative staphylococci were (33.2 %) the most common. Bacillus species were only isolated in milk samples from subclinical mastitis. Coagulase-negative staphylococci were observed in mixed infections with other bacteria in only 2.2 % of the 406 milk samples from clinical and subclinical mastitis where they were isolated together with Bacillus species in 6 of the 9 mixed infection cases. About 95 % of the milk samples from which 131 coagulase-negative staphylococci were isolated had correspondingly high somatic cell counts. The coagulase-negative staphylococci isolated most frequently were S. chromogenes (7.9 %), S. epidermidis (7.4 %) and S. hominis (5.9 %). They were all associated with high somatic cell counts. All the coagulase-negative staphylococci isolates were susceptible to cloxacillin and erythromycin, and more than 90 %of the isolates were susceptible to neomycin, penicillin and streptomycin. The highest resistance was to tetracycline (17.6 %), followed by lincomycin (13.7 %). About 8 % of the isolates were resistant to both penicillin and streptomycin.

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Using dairy herd improvement records and clinical mastitis history to identify subclinical mastitis infections at dry-off

Journal of Dairy Research ◽

10.1017/s0022029908003257 ◽

2008 ◽

Vol 75 (2) ◽

pp. 240-247 ◽

Cited By ~ 21

Author(s):

Audrey H Torres ◽

Päivi J Rajala-Schultz ◽

Fred J DeGraves ◽

Kent H Hoblet

Keyword(s):

Dairy Herd ◽

Cost Effective ◽

Subclinical Mastitis ◽

Clinical Mastitis ◽

Somatic Cell Counts ◽

Dry Cow Therapy ◽

Cell Counts ◽

On Farm ◽

First 90 Days ◽

Major Pathogens

Interest in selective dry cow therapy (SDCT) has been increasing owing to concerns over development of antimicrobial resistance. Implementation of SDCT, however, requires a quick and cost-effective on-farm method for identifying cows for treatment and cows that can be left without treatment. The objective of the present study was to evaluate the use of clinical mastitis (CM) history and somatic cell counts (SCC) from monthly Dairy Herd Improvement (DHI) records in identification of infected and uninfected cows at dry-off. A total of 647 Holstein cows were classified as uninfected or infected at dry-off based on CM history and varying number of monthly SCC records (with three different SCC cut-offs). Cows were considered uninfected based on the following criteria: (1) SCC <100 000 cells/ml and no CM during the lactation; (2) SCC <200 000 cells/ml and no CM during the lactation; (3) as criterion two, but additionally a cow was also considered uninfected if it experienced a case of CM during the first 3 months of the lactation and the SCC was <100 000 cells/ml for the rest of the lactation; (4) SCC <300 000 cells/ml and no CM during the lactation; otherwise they were considered infected. Infected and uninfected cows at dry-off were most efficiently identified using three months' SCC records with a threshold of 200 000 cells/ml for cows without CM during the lactation and a threshold of 100 000 cells/ml during the rest of lactation for cows with CM during the first 90 days in milk. Moreover, this criterion also most efficiently identified cows infected with major pathogens only at dry-off. The success of the criteria used for identifying infected and uninfected cows will, however, depend on herd characteristics, such as prevalence of infection and type of pathogens present in the herd.

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Application of the Support Vector Machine to Predict Subclinical Mastitis in Dairy Cattle

The Scientific World JOURNAL ◽

10.1155/2013/603897 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 8

Author(s):

Nazira Mammadova ◽

İsmail Keskin

Keyword(s):

Support Vector Machine ◽

Dairy Cattle ◽

Somatic Cell ◽

Control Period ◽

Subclinical Mastitis ◽

Clinical Mastitis ◽

Support Vector ◽

Cross Sectional ◽

Somatic Cell Counts ◽

Cell Counts

This study presented a potentially useful alternative approach to ascertain the presence of subclinical and clinical mastitis in dairy cows using support vector machine (SVM) techniques. The proposed method detected mastitis in a cross-sectional representative sample of Holstein dairy cattle milked using an automatic milking system. The study used such suspected indicators of mastitis as lactation rank, milk yield, electrical conductivity, average milking duration, and control season as input data. The output variable was somatic cell counts obtained from milk samples collected monthly throughout the 15 months of the control period. Cattle were judged to be healthy or infected based on those somatic cell counts. This study undertook a detailed scrutiny of the SVM methodology, constructing and examining a model which showed 89% sensitivity, 92% specificity, and 50% error in mastitis detection.

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Influence of the lactoperoxidase system on susceptibility of the udder toStreptococcus uberisinfection

Journal of Dairy Research ◽

10.1017/s0022029900033033 ◽

1986 ◽

Vol 53 (4) ◽

pp. 507-514 ◽

Cited By ~ 45

Author(s):

Valerie M. E. Marshall ◽

Wendy M. Cole ◽

A. John Bramley

Keyword(s):

Mammary Gland ◽

Somatic Cell ◽

Inhibitory Activity ◽

Inhibitory System ◽

Somatic Cell Counts ◽

Streptococcus Uberis ◽

Cell Counts ◽

Lactoperoxidase System ◽

Colony Forming Units ◽

Lactating Mammary Gland

SummaryLactoperoxidase (LP), thiocyanate (SCN-), pH and somatic cell counts (SCC) were measured in mammary secretions from 20 cows collected 14 d before drying-off, 7 and 21 d after drying-off, and 3–18 d postcalving. The inhibitory activity of the secretions onStreptococcus uberiswas determined and the susceptibility of the udder to infection by this organism was tested by intramammary infusion of 250 colony forming units at the above stages. LP, SCN-, pH and SCO increased during involution and fell postcalving. The secretions collected before drying-off, 7 d after drying-off and postcalving inhibited growth ofStr. uberis.; those collected 21 d after drying-off did not. Inhibitory activity in pre-drying-off secretions was destroyed by heating and restored by addition of LP, glucose and glucose oxidase, but addition of these substances to secretion 21 d after drying-off did not provide a full inhibitory system. The growth ofStr. uberisin the secretions was correlated with intramammary susceptibility, since challenges withStr. uberisat 14 d before drying-off, at 7 and 21 d after drying-off and postcalving led to 43·8, 25·0, 81·3 and 37·5% of quarters becoming infected. It is suggested that the LP/SCN-/H2O2system plays a role in protecting the lactating mammary gland from infection withStr. uberisbut becomes ineffective as involution progresses.

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First Insights into the Evolution of Streptococcus uberis: a Multilocus Sequence Typing Scheme That Enables Investigation of Its Population Biology

Applied and Environmental Microbiology ◽

10.1128/aem.72.2.1420-1428.2006 ◽

2006 ◽

Vol 72 (2) ◽

pp. 1420-1428 ◽

Cited By ~ 43

Author(s):

Tracey J. Coffey ◽

Gillian D. Pullinger ◽

Rachel Urwin ◽

Keith A. Jolley ◽

Stephen M. Wilson ◽

...

Keyword(s):

Multilocus Sequence Typing ◽

Population Biology ◽

Clonal Complex ◽

Bovine Mastitis ◽

Housekeeping Gene ◽

Global Scale ◽

Streptococcus Uberis ◽

Capsule Production ◽

Sequence Types ◽

Better Than

ABSTRACT Intramammary infection with Streptococcus uberis is a common cause of bovine mastitis throughout the world. Several procedures to differentiate S. uberis isolates have been proposed. However, all are prone to interlaboratory variation, and none is suitable for the description of the population structure. We describe here the development of a multilocus sequence typing (MLST) scheme for S. uberis to help address these issues. The sequences of seven housekeeping gene fragments from each of 160 United Kingdom milk isolates of S. uberis were determined. Between 5 and 17 alleles were obtained per locus, giving the potential to discriminate between 1.3 × 107 sequence types. In this study, 57 sequence types (STs) were identified. Statistical comparisons between the maximum-likelihood trees constructed by using the seven housekeeping gene fragments showed that the congruence was no better than that between each tree and trees of random topology, indicating there had been significant recombination within these loci. The population contained one major lineage (designated the ST-5 complex). This dominated the population, containing 24 STs and representing 112 isolates. The other 33 STs were not assigned to any clonal complex. All of the isolates in the ST-5 lineage carried hasA, a gene that is essential for capsule production. There was no clear association between ST or clonal complex and disease. The S. uberis MLST system offers researchers a valuable tool that allows further investigation of the population biology of this organism and insights into the epidemiology of this disease on a global scale.

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Characterization of Pasteurella multocida isolated from dead rabbits with respiratory disease in Fujian, China

10.21203/rs.2.12451/v2 ◽

2019 ◽

Author(s):

Jinxiang Wang ◽

Lei Sang ◽

Shikun Sun ◽

Yanfeng Chen ◽

Dongjin Chen ◽

...

Keyword(s):

Respiratory Disease ◽

Pasteurella Multocida ◽

Sequence Type ◽

Economic Losses ◽

Pcr Screening ◽

Resistance Rates ◽

And Control ◽

First Time ◽

Sequence Types

Abstract Background: Pasteurella multocida is one of the important pathogens that infect rabbits, causing major economic losses in commercial rabbit farming. In this study, 205 P. multocida isolates recovered from lungs of dead rabbits with respiratory disease were defined by capsular serogroups, lipopolysaccharide (LPS) genotypes and multi-locus sequence types, screened virulence factors and antimicrobial susceptibility. Results: The 205 isolates were assigned into 2 capsular types, A and D, and 2 LPS genotypes, L3 and L6. When combining capsular types with LPS genotypes, 4 serotypes were detected. A:L3 (51.22%, 105/205) was the most predominant serotype, followed by A:L6 (24.88%, 51/205), D:L6 (19.02%, 39/205) and D:L3 (4.88%, 10/205). The 205 isolates were grouped into 3 sequence types, ST10, ST11 and ST12. ST12 (56.10%, 115/205) was the most prevalent sequence type, followed by ST10 (24.88%, 51/205) and ST11 (19.02%, 39/205). In the 205 isolates, virulence associated genes ptfA , fur , hgbB , ompA , ompH and oma87 were positive in the PCR screening, whereas the toxA and tbpA genes were negative. Notably, the 156 capsular serogroup A isolates carried the pmHAS gene. All the 205 isolates were susceptible to most of the used antibiotics, except for streptomycin, gentamycin, kanamycin and ceftriaxone, and the resistance rates of which were 27.80%, 15.61%, 9.27% and 2.44%, respectively. Conclusions: This study, for the first time, described the prevalence and characteristics of P. multocida causing respiratory disease in rabbits in Fujian Province, which might be useful for tracking the epidemic strains and development of efficient vaccines and methods to prevent and control the pathogen.

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Variation in Campylobacter Multilocus Sequence Typing Subtypes from Chickens as Detected on Three Plating Media

Journal of Food Protection ◽

10.4315/0362-028x.jfp-16-188 ◽

2016 ◽

Vol 79 (11) ◽

pp. 1986-1989 ◽

Cited By ~ 3

Author(s):

M. E. BERRANG ◽

S. R. LADELY ◽

R. J. MEINERSMANN ◽

J. E. LINE ◽

B. B OAKLEY ◽

...

Keyword(s):

Campylobacter Jejuni ◽

Multilocus Sequence Typing ◽

Clonal Complex ◽

Sequence Type ◽

Campylobacter Coli ◽

Processing Plant ◽

Full Genome Sequencing ◽

Multiple Sequence ◽

Commercial Broiler ◽

Sequence Types

ABSTRACT The objective of this study was to compare subtypes of Campylobacter jejuni and Campylobacter coli detected on three selective Campylobacter plating media to determine whether each medium selected for different subtypes. Fifty ceca and 50 carcasses (representing 50 flocks) were collected from the evisceration line in a commercial broiler processing plant. Campylobacter was cultured and isolated from cecal contents and carcass rinses on Campy-Cefex, Campy Line, and RF Campylobacter jejuni/coli agars. When a positive result was obtained with all three media, one colony of the most prevalent morphology on each medium was selected for further analysis by full genome sequencing and multilocus sequence typing. Sequence types were assigned according to PubMLST. A total of 49 samples were positive for Campylobacter on all three media. Forty samples contained only C. jejuni, three had only C. coli, and both species were detected in six samples. From 71% of samples, Campylobacter isolates of the same sequence type were recovered on all three media. From 81.6% of samples, isolates were all from the same clonal complex. From significantly fewer samples (26%, P < 0.01), one medium recovered an isolate with a sequence type different from the type recovered on the other two media. When multiple sequence types were detected, six times the medium with the odd sequence type was Campy-Cefex, four times it was Campy-Line, and six times it was RF Campylobacter jejuni/coli. From one sample, three sequence types were detected. In most cases, all three plating media allowed detection of the same type of Campylobacter from complex naturally contaminated chicken samples.

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Subclinical mastitis in dairy cows in Swiss organic and conventional production systems

Journal of Dairy Research ◽

10.1017/s002202990600210x ◽

2006 ◽

Vol 74 (1) ◽

pp. 86-92 ◽

Cited By ~ 38

Author(s):

Markus Roesch ◽

Marcus G Doherr ◽

Walter Schären ◽

Melchior Schällibaum ◽

Jürg W Blum

Keyword(s):

Dairy Cows ◽

Production Systems ◽

Post Partum ◽

Subclinical Mastitis ◽

Coagulase Negative Staphylococci ◽

Somatic Cell Counts ◽

Milk Samples ◽

California Mastitis Test ◽

Cell Counts ◽

Conventional Production

The objective was to compare the prevalence of subclinical mastitis (SM) and of udder pathogens in 60 Swiss organic (OP) and 60 conventional production systems (CP). Cows (n=970) were studied for SM prevalence and udder pathogens at median 31 d and 102 d post partum. Cows showing a [ges ]1+ positive California Mastitis Test (CMT) in at least one quarter were considered to have SM. Cow-level prevalences of SM for visits at 31 d and 102 d post partum (39% and 40% in OP and 34% and 35% in CP) were similar, but quarter-level prevalences of SM were higher (P<0·02) in OP than CP (15% and 18% in OP and 12% and 15% in CP). Median somatic cell counts in milk at 31 d post partum were higher (P<0·05) in OP than CP cows (43000 and 28000 cells/ml, respectively), but were similar at 102 d post partum in OP and CP cows (45000 and 38000 cells/ml, respectively). In milk samples from quarters showing a CMT reaction [ges ]2+ the prevalences of coagulase negative staphylococci were lower (P<0·05) at 102 d post partum, whereas prevalences of non-agalactiae streptococci were higher (P<0·05) in OP than in CP cows at 31 d and 102 d post partum. In conclusion, under Swiss conditions, subclinical mastitis is a greater problem in organic than in conventional production systems, but differences are not marked.

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Presence of cathelicidin-1 in milk as an indicator of the severity of mammary infection in ewes

Current Proteomics ◽

10.2174/1570164617999200510234638 ◽

2020 ◽

Vol 17 ◽

Author(s):

Angeliki I. Katsafadou ◽

Natalia G.C. Vasileiou ◽

George T. Tsangaris ◽

Katerina S. Ioannidi ◽

Athanasios K. Anagnostopoulos ◽

...

Keyword(s):

Somatic Cell ◽

Milk Yield ◽

Inverse Correlation ◽

Subclinical Mastitis ◽

Clinical Mastitis ◽

Somatic Cell Counts ◽

Milk Samples ◽

Cell Counts ◽

The Mean ◽

Important Disease

: Aims: The importance of cathelicidin-1 as an indicator of the severity of mammary infection in ewes. Background: Mastitis is an important disease of sheep, affecting their health and welfare. Objective: The association of the presence of cathelicidin-1 in milk samples from ewes with mastitis with the severity of the infection. Methods: Ewes were intramammarily inoculated with Mannheimia haemolytica or Staphylococcus chromogenes. Conventional (clinical, bacteriological and cytological examinations; milk yield measurements) and proteomics evaluation (2-DE, MALDI-TOF MS) to record cathelicidin-1 spot optical densities in milk samples were recorded. Results: Ewes challenged with M. haemolytica developed clinical and ewes challenged with S. chromogenes subclinical mastitis (P=0.05). The challenge organism was isolated from milk samples from inoculated mammary glands; increased somatic cell counts were also recorded. Cathelicidin-1 was detected in milk samples from the inoculated side of udders of all ewes. Mean spot density of cathelicidin-1 from samples from inoculated glands of ewes challenged with M. haemolytica was higher than from ewes challenged with S. chromogenes: 2896 ± 973 versus 1312 ± 361 (P =0.034). There were significant correlations between the presence of clinical mastitis / somatic cell counts with the spot density of cathelicidin-1 on 2-DE gels (P=0.043 and P=0.023, respectively). There was also a significant inverse correlation between the mean spot densities of cathelicidin-1 in milk samples and the milk yield of respective ewes on D10 (P =0.031). Conclusion: Potentially, cathelicidin-1 could be used as a marker to indicate the severity of damage to the mammary parenchyma.

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