scholarly journals Prevalence and distribution of multilocus sequence types of Staphylococcus aureus isolated from bulk tank milk and cows with mastitis in Pennsylvania

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248528
Author(s):  
Asha Thomas ◽  
Shubhada Chothe ◽  
Maurice Byukusenge ◽  
Tammy Mathews ◽  
Traci Pierre ◽  
...  
Keyword(s):  
Bovine Mastitis ◽  
Diagnostic Laboratory ◽  
Bulk Tank Milk ◽  
Enterotoxin Genes ◽  
Penn State ◽  
Bulk Tank ◽  
Mastitic Milk ◽  
Genotypic Characteristics ◽  
First Time ◽  
Sequence Types

A total of 163 S. aureus isolates; 113 from mastitic milk (MM) and 50 from bulk tank milk (BTM) (2008, 2013–2015) submitted for bacteriologic analysis at the Penn State Animal Diagnostic Laboratory were examined for their phenotypic and genotypic characteristics. Multi-locus sequence typing (MLST) analysis identified 16 unique sequence types (STs) which belonged to eight clonal complexes (CCs). Majority of the isolates were variants of CC97 (68.7%) and CC151 (25.1%). CC97 comprised of seven STs, of which two were new STs (ST3273, ST3274), while CC151 comprised of three STs of which ST3272 was identified for the first time. Several farms had more than one ST type that were either members of the same clonal complex or unrelated STs. On one farm, six different STs of both categories were seen over the years within the farm. It was observed that ST352 and ST151 were the two main clonal populations in cattle not only in Pennsylvania but also globally. Most isolates were susceptible to all the antibiotics evaluated. 6.7% of isolates showed resistance to vancomycin and penicillin. Two isolates of ST398 showed multidrug resistance (>3 antibiotics) against clindamycin, erythromycin, tetracycline, and penicillin. It was noted that 59 of 163 (36.2%) isolates encoded for enterotoxigenic genes. Enterotoxin genes seg/sei accounted for ~85% of enterotoxin positive isolates. Toxic shock syndrome gene tsst-1 alone was positive in two isolates (ST352, ST 2187). 97.5% of CC151 isolates were enterotoxin seg/sei positive. Most isolates were positive for lukED (95%) and lukAB (96.3%) leukotoxin genes. Bovine specific bi-component leucocidin lukMF’ was present in 54% of isolates. A prominent observation of this study was the explicit association of lukMF’ with lineages ST151 and ST352. In conclusion, the findings of the study, suggest that small number of S. aureus STs types (ST352, ST2187, ST3028, and ST151) are associated with majority of cases of bovine mastitis in Pennsylvania dairy farms. It was observed that one ST of S. aureus predominated in the herd and this ST can coexist with several other ST types of S. aureus strains. When STs were interpreted along with virulence, leucocidin genes and antimicrobial resistance, ST-variants allowed better interpretation of the S. aureus molecular epidemiologic findings specifically for tracing recurrence or persistence of infections in cow over time, among cows in the herd, and between herds in Pennsylvania.

scholarly journals Occurrence of enterotoxin genes and macrorestriction analysis of Staphylococcus aureus isolated from bovine mastitis and bulk-tank milk samples in Italy. An epidemiological study

2004 ◽  
Vol 3 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Andrea Serraino ◽  
Leonardo Alberghini ◽  
Maria Cristina Fontana ◽  
Cosima Annemüller ◽  
Christoph Lämmler ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Epidemiological Study ◽  
Bovine Mastitis ◽  
Bulk Tank Milk ◽  
Milk Samples ◽  
Enterotoxin Genes ◽  
Bulk Tank

scholarly journals Characterization of Virulence Factors in Enterotoxin-Producing Staphylococcus Aureus From Bulk Tank Milk

2021 ◽  
Author(s):  
Hye-Ri Jung ◽  
Young Ju Lee
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Bovine Mastitis ◽  
Bulk Tank Milk ◽  
Genetic Characteristics ◽  
Enterotoxin Genes ◽  
High Prevalence ◽  
Bulk Tank

Abstract Background: Staphylococcus aureus, a persistent and chronic mastitis-causing pathogen, produces various virulence factors, including enterotoxins. This study analyzed the genetic characteristics of bovine mastitis-related virulence factors to evaluate potential pathogenesis in S. aureus isolated from bulk tank milk.Results: Among 93 S. aureus isolates from 396 dairy farms in six factories operated by three dairy companies in Korea, 40 (43.0%) isolates carried at least one or more enterotoxin genes and there were significant differences between factories within the same company (p < 0.05). Moreover, S. aureus carrying enterotoxin genes showed a higher prevalence in all virulence genes tested in this study except for pvl and lukM, which were not detected in any isolate, than the isolates without enterotoxin genes. In particular, the prevalence of six genes (hla, hlb, lukED, fnbA, clfA, and clfB) was significantly higher in S. aureus carrying enterotoxin genes than isolates without enterotoxin genes (p < 0.05). The most common multilocus sequence type (ST) of 40 enterotoxin-producing isolates was ST188, and all isolates of ST188 harbored the see gene. However, none of the isolates of ST1 and ST72 carried the see gene, and all isolates of ST1 carried the seh gene.Conclusions: Although S. aureus isolated from bulk tank milk, not from mastitis, had a high prevalence of enterotoxins and virulence factors simultaneously, posing a public health threat. Moreover, high enterotoxins in bulk tank milk may be reflected by poor hygiene; therefore, it is important to develop strong monitoring and sanitation programs to ensure that dairy factories produce hygienic milk.

Dissemination and Characteristics of High-Level Erythromycin-Resistant Enterococcus Faecalis From Bulk Tank Milk of Dairy Companies in Korea

2021 ◽  
Author(s):  
Yu Jin Lee ◽  
Koeun Kim ◽  
Young Ju Lee
Keyword(s):  
Enterococcus Faecalis ◽  
Resistance Genes ◽  
Virulence Genes ◽  
Bovine Mastitis ◽  
Bulk Tank Milk ◽  
Significant Difference ◽  
Bulk Tank ◽  
Environmental Pathogens ◽  
High Level ◽  
Genotypic Characteristics

Abstract Background: Enterococci are environmental pathogens that can cause bovine mastitis and macrolides are widely used for the treatment of bovine mastitis caused by staphylococci and streptococci/enterococci. The aim of this study was performed to compare the phenotypic and genotypic characteristics of high-level erythromycin-resistant (HLER) Enterococcus faecalis (E. faecalis) collected from bulk tank milk of four dairy companies (A, B, C, and D) in Korea. Results: Although isolates from company D showed the highest prevalence of E. faecalis, the prevalence of HLER E. faecalis in company A (73.1%) and C (57.0%) was significantly higher than company D (33.9%) (P < 0.05). A total of 149 HLER E. faecalis isolates showed high rates of resistance to tetracycline (93.3%), followed by doxycycline (70.0%), and chloramphenicol (48.3%). In the distribution of macrolides resistance genes, 147 (98.7%) isolates carried ermB gene alone, and two isolates carried both ermA and ermB genes. No isolates carried ermC, msrA, msrC, or mef genes. In the distribution of other resistance genes, 72 (48.3%) and 60 (40.3%) isolates carried both tetM and tetL genes, and tetM gene alone, respectively, and 38 (25.5%) isolates carried optrA gene. For aminoglycosides resistance genes, the prevalence of both aac(6′)Ie-aph(2″)-la and ant(6′)-Ia genes (43.0%) was the highest. Moreover, 104 (70.0%) isolates harbored Int-Tn gene carrying the Tn916/1545-like transposon. Although the distribution of ermB gene showed no significant difference between the dairy companies, the prevalence of other resistance genes and transposons showed a significant difference between the dairy companies (P < 0.05). Virulence genes, such as ace (99.3%), cad1 and efaA (each 98.7%), and gelE (83.9%), were also highly conserved in the 149 HLER E. faecalis isolates. Conclusions: Our results indicated that HLER E. faecalis isolates from bulk tank milk showed significant differences in phenotypic and genotypic characteristics between the dairy companies. In addition, the prevalence of resistance genes and virulence factors was also high in HLER E. faecalis isolates.

scholarly journals Mycoplasmal mastitis in dairy cows in the Moghan region of Ardabil State, Iran : short communication

2006 ◽  
Vol 77 (4) ◽  
Author(s):  
C. Ghazaei
Keyword(s):  
Dairy Cows ◽  
Short Communication ◽  
Bovine Mastitis ◽  
Subclinical Mastitis ◽  
Clinical Mastitis ◽  
Mycoplasma Bovis ◽  
Bulk Tank Milk ◽  
Milk Samples ◽  
The World ◽  
Bulk Tank

Mycoplasmas are an important and economically significant cause of mastitis in dairy cows in various parts of the world. The organisms are highly contagious, with the main reservoir of infection originating from cows with subclinical mastitis. In 1998 the 1st cases of bovine mastitis due to Mycoplasma bovis were diagnosed in Ardabil State, Iran. An investigation was carried out with the aim of establishing the extent of mycoplasma infections in dairy cows in Ardabil State. Milk samples obtained from 80 cows with clinical mastitis were cultured in the laboratory for the presence of mycoplasmas. Similarly, 48 bulk-tank milk samples were examined for the presence of mycoplasmas. A modified Hayflick broth was used to isolate the mycoplasmas and an immunoperoxidase test used for the species identification of the isolates. Mycoplasma bovis was isolated from 39 (48.75 %) of the clinical mastitis samples and from 48 of the bulk-tank milk samples tested. This indicated that mycoplasma udder infections were more prevalent in dairy cows in Ardabil State than previously thought.

scholarly journals Estimated herd prevalence and sequence types of Coxiella burnetii in bulk tank milk samples from commercial dairies in Indiana

2015 ◽  
Vol 11 (1) ◽  
Author(s):  
Amy E. Bauer ◽  
Sonora Olivas ◽  
Maria Cooper ◽  
Heidie Hornstra ◽  
Paul Keim ◽  
...  
Keyword(s):  
Coxiella Burnetii ◽  
Bulk Tank Milk ◽  
Herd Prevalence ◽  
Milk Samples ◽  
Bulk Tank ◽  
Sequence Types

Prevalence of Pathogens Associated with Bovine Mastitis in Bulk Tank Milk in Mexico

2008 ◽  
Vol 1149 (1) ◽  
pp. 300-302 ◽  
Author(s):  
Rosa E. Miranda-Morales ◽  
Verónica Rojas-Trejo ◽  
Raúl Segura-Candelas ◽  
Erika M. Carrillo-Casas ◽  
Ma Guadalupe Sánchez-Gonzalez ◽  
...  
Keyword(s):  
Bovine Mastitis ◽  
Bulk Tank Milk ◽  
Bulk Tank

scholarly journals Comparative analysis of genetic characterization of β-lactam-resistant Escherichia coli from bulk tank milk in Korea

2021 ◽  
Vol 74 (1) ◽  
Author(s):  
Hye-Ri Jung ◽  
Koeun Kim ◽  
Young Ju Lee
Keyword(s):  
Escherichia Coli ◽  
Clinical Mastitis ◽  
Phylogenetic Groups ◽  
Bulk Tank Milk ◽  
Genetic Characteristics ◽  
E Coli ◽  
Intestinal Infections ◽  
Antimicrobial Resistance Genes ◽  
Bulk Tank ◽  
Genotypic Characteristics

Abstract Background This study was conducted to analyze the genetic characteristics of 41 β-lactam-resistant Escherichia coli isolates, which are one of the common causes of environmental mastitis, isolated from the bulk tank milk of 290 dairy farms in five factories operated by three dairy companies in Korea. Results Analysis of the phenotypic and genotypic characteristics of β-lactam-resistant E. coli isolates revealed differences between factories even within the same company. Isolates from factory A1 and C1 showed high resistance to cephalothin (76.9 and 100%, respectively), which is a first-generation cephalosporins, whereas resistance to tetracycline was showed by only the isolates from factories B1 (60.0%), C2 (66.7%), and C3 (100%). Although all the 41 β-lactam-resistant E. coli isolates were positive for blaOXA-1, blaTEM-1 was highly prevalent in isolates from factories C2 (100%) and C3 (100%). Among 17 isolates resistant to both β-lactams and aminoglycosides, the most common multilocus sequence type was ST399 (13isolates, 76.5%). Furthermore, 2 (11.8%) and 12 (70.6%) isolates belonged to the phylogenetic groups B2 and D, respectively, which are invasive strains that cause intestinal infections, respectively. The predominant serogroup was O15 (70.6%), which is a globally distributed extraintestinal pathogen. Interestingly, one isolate from factory A1 belonged to O157 and carried six virulence genes, simultaneously. Conclusions Although E. coli isolates were isolated from bulk tank milk, and not the clinical mastitis samples, the presence of the phylogenetic groups B2 and D, and the serogroups O15 and O157, which harbor antimicrobial resistance genes and virulence factors, can pose a threat to public health.

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