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Sesso L, Vanzetti T, Weber J, Vaccani M, Scettrini PR, Sartori C, Ivanovic I, Romanỏ A, Bodmer M, Bacciarini LN, Struchen R, Steiner A, Graber HU. District-Wide Herd Sanitation and Eradication of Intramammary Staphylococcus aureus Genotype B Infection in Dairy Herds in Ticino, Switzerland. J Dairy Sci 2024:S0022-0302(24)00809-9. [PMID: 38788844 DOI: 10.3168/jds.2023-24245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 04/05/2024] [Indexed: 05/26/2024]
Abstract
The present study demonstrates successful herd sanitation and eradication of contagious mastitis caused by Staphylococcus aureus genotype B (S. aureus GTB) in an entire Swiss district (Ticino) including 3,364 dairy cows from 168 farms. Herd sanitation included testing of all cows using a highly GTB specific and sensitive qPCR assay, implementation of related on-farm measures, appropriate antibiotic therapy of GTB-positive cows and culling of therapy-resistant animals, respectively. A treatment index was used as an objective criterion to select GTB-positive cows eligible for culling and replacement payment. 62 herds (37%) were initially GTB-positive with a cow prevalence between 10% and 100% and were submitted to sanitation. Twenty mo after the start of the campaign, all these herds were free from S. aureus GTB, whereby 73% of them were sanitized during the first 7 mo. At the cow level, a total of 343 animals were infected. 50 of them were immediately culled and financially compensated based on their treatment index value. The remaining 293 cows were intramammarily treated with antibiotics either during lactation using the combination of cephalexin-kanamycin or penicillin-gentamicin or at dry-off using cloxacillin. Out of these cows, 275 (93.9%) were treated successfully meaning that their milk was twice GTB-negative by qPCR after therapy. For lactational treatment, control samples were taken ≥10 and ≥20 d after treatment, for dry off treatment ≥14 and ≥24 d after parturition. Neither lactation number nor SCC before treatment of the cow nor the type of therapy were associated with therapeutic cure. Using data of 30 GTB-positive and 71 GTB-negative herds (1855 observations), the impact of GTB sanitation on bulk tank milk SCC (BTSCC) was evaluated applying a linear mixed statistical model. In the year before sanitation, BTSCC was always higher in GTB positive than in GTB negative herds. After the start of the campaign, BTSCC declined rapidly in the herds under GTB sanitation and achieved values that no longer differed statistically from those of GTB-free herds after only 2 mo, remaining very similar for the rest of the campaign. The farmers were very satisfied with the outcome of the campaign as all GTB positive herds could be sanitized rapidly, sanitation was sustainable, and milk quality increased.
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Affiliation(s)
- L Sesso
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, 3012 Bern, Switzerland; Institute of Microbiology, Department of Environment, Constructions and Design, University of Applied Sciences of Southern Switzerland (SUPSI), 6850 Mendrisio, Switzerland
| | - T Vanzetti
- Repubblica e Cantone Ticino, Ufficio del veterinario cantonale, 6500 Bellinzona, Switzerland
| | - J Weber
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, 3012 Bern, Switzerland
| | - M Vaccani
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, 3012 Bern, Switzerland; Repubblica e Cantone Ticino, Ufficio del veterinario cantonale, 6500 Bellinzona, Switzerland
| | - P Riva Scettrini
- Repubblica e Cantone Ticino, Ufficio della consulenza agricola, 6501 Bellinzona, Switzerland
| | - C Sartori
- Agroscope, Food Microbial Systems, 3003 Bern, Switzerland
| | - I Ivanovic
- Agroscope, Food Microbial Systems, 3003 Bern, Switzerland
| | - A Romanỏ
- Agroscope, Food Microbial Systems, 3003 Bern, Switzerland
| | - M Bodmer
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, 3012 Bern, Switzerland
| | - L N Bacciarini
- Repubblica e Cantone Ticino, Ufficio del veterinario cantonale, 6500 Bellinzona, Switzerland
| | - R Struchen
- Federal Food Safety and Veterinary Office, 3003 Bern, Switzerland
| | - A Steiner
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, 3012 Bern, Switzerland
| | - H U Graber
- Agroscope, Food Microbial Systems, 3003 Bern, Switzerland.
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Nemati G, Romanó A, Wahl F, Berger T, Rojo LV, Graber HU. Bovine Staphylococcus aureus: a European study of contagiousness and antimicrobial resistance. Front Vet Sci 2023; 10:1154550. [PMID: 37206433 PMCID: PMC10188956 DOI: 10.3389/fvets.2023.1154550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 04/04/2023] [Indexed: 05/21/2023] Open
Abstract
In dairy herds managements, mastitis is the leading cause of economic losses. One of the most important pathogens responsible for intra-mammary infections is Staphylococcus aureus. The genetic properties of S. aureus have a strong influence on its pathogenicity and contagiousness. In this study, we aimed to obtain a comprehensive overview of the key bovine S. aureus clinical properties, such as contagiousness and antimicrobial resistance, present in European strains. For this, 211 bovine S. aureus strains from ten European countries that were used in a previous study were used in this study. Contagiousness was assessed using qPCR for the detection of the marker gene adlb. Antimicrobial resistance was evaluated using a broth microdilution assay and mPCR for the detection of genes involved in penicillin resistance (blaI, blaR1, and blaZ). It was found that adlb was present in CC8/CLB strains; however, in Germany, it was found in CC97/CLI and in an unknown CC/CLR strains. CC705/CLC strains from all countries were found to be susceptible to all tested antibiotics. Major resistance to penicillin/ampicillin, chloramphenicol, clindamycin and tetracycline was detected. Resistance to oxacillin, trimethoprim/sulfamethoxazole and cephalosporins was rarely observed. In addition, contagiousness and antibiotic resistance seem to correlate with different CCs and genotypic clusters. Hence, it is recommended that multilocus sequence typing or genotyping be utilized as a clinical instrument to identify the most appropriate antibiotic to use in mastitis treatment. Actualization of the breakpoints of veterinary strains is necessary to address the existing antibiotic resistance of the bacteria involved in veterinary mastitis.
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Affiliation(s)
- Ghazal Nemati
- Food Microbial Systems, Risk Assessment and Mitigation Group, Agroscope, Bern, Switzerland
- Food Microbial Systems, Microbiological Safety of Foods of Animal Origin Group, Agroscope, Bern, Switzerland
- *Correspondence: Ghazal Nemati
| | - Alicia Romanó
- Food Microbial Systems, Microbiological Safety of Foods of Animal Origin Group, Agroscope, Bern, Switzerland
| | - Fabian Wahl
- Food Microbial Systems, Agroscope, Bern, Switzerland
| | - Thomas Berger
- Food Microbial Systems, Risk Assessment and Mitigation Group, Agroscope, Bern, Switzerland
| | - Laura Vazquez Rojo
- Food Microbial Systems, Microbiological Safety of Foods of Animal Origin Group, Agroscope, Bern, Switzerland
| | - Hans Ulrich Graber
- Food Microbial Systems, Microbiological Safety of Foods of Animal Origin Group, Agroscope, Bern, Switzerland
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3
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A stochastic modelling approach to determine the effect of diverse Staphylococcus aureus strains on the economic and epidemiological outcomes of mastitis intervention strategies in dairy cattle. Prev Vet Med 2021; 199:105566. [PMID: 34968887 DOI: 10.1016/j.prevetmed.2021.105566] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 10/15/2021] [Accepted: 12/19/2021] [Indexed: 11/21/2022]
Abstract
Staphylococcus aureus (S. aureus) strains with considerable genetic and phenotypic differences have previously been identified. The economic and epidemiologic impact of S. aureus mastitis has been investigated, but none of these studies took differences between strains into account. Here we aimed to investigate how differences between S. aureus strains affect the economic and epidemiologic outcome of various intervention strategies against clinical and subclinical intramammary infections. Five S. aureus strains were modelled using a stochastic bio-economic model simulating a dairy herd of 200 cows using single-day time steps. The strain characteristics of the five simulated S. aureus strains (general, contagious, spill-over, clinical and persistent) were based on divergent phenotypes as described in literature. Outcomes of the model included incidence (both clinical and subclinical), number of antibiotic treatment days, number of culled cows, and net income. Intervention strategies against clinical and subclinical intramammary infections were based on (variations of) intramammary antibiotic treatment, testing, and culling. Both single and multiple pathogen (intramammary infection caused by S. aureus, Escherichia coli, and non-aureus staphylococci) scenarios were simulated to determine the effect of the five S. aureus strains on the impact of 19 different intervention strategies. The results showed that the incidence (both clinical and subclinical), number of treatment days, number of culled cows, and net income varied considerably for the different S. aureus strains. Comparison of the model outcomes within and between strains showed that for most intervention strategies the relative impact differed per strain. However, the intervention strategy with the best outcome for most variables and strains was the culling of cows with a recovery probability lower than 50%. This shows that the relative economic and epidemiologic impact of most of the modelled intervention strategies were strain-dependent, while some intervention strategies were not strain-dependent. From this, we conclude that, depending on the intervention strategy applied on a farm, it could be advantageous to type S. aureus to determine whether it would be economically and epidemiologically beneficial for the existing intervention strategy to be changed.
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Pacha PA, Munoz MA, González-Rocha G, San Martín I, Quezada-Aguiluz M, Aguayo-Reyes A, Bello-Toledo H, Latorre AA. Molecular diversity of Staphylococcus aureus and the role of milking equipment adherences or biofilm as a source for bulk tank milk contamination. J Dairy Sci 2020; 104:3522-3531. [PMID: 33358810 DOI: 10.3168/jds.2020-19121] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/07/2020] [Indexed: 01/14/2023]
Abstract
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.
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Affiliation(s)
- P A Pacha
- Departamento de Patología y Medicina Preventiva-Departamento de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán 3812120, Chile
| | - M A Munoz
- Departamento de Patología y Medicina Preventiva-Departamento de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán 3812120, Chile
| | - G González-Rocha
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción 4070386, Chile; Millennium Nucleus on Interdisciplinary Approach to Antimicrobial Resistance, MICROB, Las Condes 7590943, Chile
| | - I San Martín
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción 4070386, Chile
| | - M Quezada-Aguiluz
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción 4070386, Chile; Departamento de Medicina Interna, Facultad de Medicina, Universidad de Concepción, Concepción 4070386, Chile
| | - A Aguayo-Reyes
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción 4070386, Chile
| | - H Bello-Toledo
- Laboratorio de Investigación en Agentes Antibacterianos, Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción 4070386, Chile
| | - A A Latorre
- Departamento de Patología y Medicina Preventiva-Departamento de Ciencia Animal, Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán 3812120, Chile.
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5
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Li Z, Liu L, Rao Y, Ran L, Wu T, Nie R, Anna DS, Li Y, Che Z. Mechanical and antibacterial properties of oriented poly(lactic acid). POLYM ENG SCI 2019. [DOI: 10.1002/pen.25214] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Zhengqiu Li
- School of Material Science and EngineeringXihua University Chengdu 610039 China
| | - Lei Liu
- School of Food Science and BioengineeringXihua University Chengdu 610039 China
| | - Yu Rao
- School of Food Science and BioengineeringXihua University Chengdu 610039 China
| | - Longchang Ran
- School of Material Science and EngineeringXihua University Chengdu 610039 China
| | - Ting Wu
- School of Material Science and EngineeringXihua University Chengdu 610039 China
| | - Rong Nie
- School of Food Science and BioengineeringXihua University Chengdu 610039 China
| | - De Schutter Anna
- Department of NeuroscienceUniversity of California, Los Angeles Los Angeles California
| | - Yalin Li
- School of Food Science and BioengineeringXihua University Chengdu 610039 China
| | - Zhenming Che
- School of Food Science and BioengineeringXihua University Chengdu 610039 China
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6
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Leuenberger A, Sartori C, Boss R, Resch G, Oechslin F, Steiner A, Moreillon P, Graber H. Genotypes of Staphylococcus aureus: On-farm epidemiology and the consequences for prevention of intramammary infections. J Dairy Sci 2019; 102:3295-3309. [DOI: 10.3168/jds.2018-15181] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 12/09/2018] [Indexed: 12/22/2022]
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7
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Molecular characterisation and biofilm production in Staphylococcusaureus isolates from the dairy production chain in Northern Italy. Int Dairy J 2019. [DOI: 10.1016/j.idairyj.2018.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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8
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Sartori C, Boss R, Bodmer M, Leuenberger A, Ivanovic I, Graber H. Sanitation of Staphylococcus aureus genotype B-positive dairy herds: A field study. J Dairy Sci 2018; 101:6897-6914. [DOI: 10.3168/jds.2017-13937] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 03/27/2018] [Indexed: 11/19/2022]
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9
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Cousin ME, Härdi-Landerer MC, Völk V, Bodmer M. Control of Staphylococcus aureus in dairy herds in a region with raw milk cheese production: farmers' attitudes, knowledge, behaviour and belief in self-efficacy. BMC Vet Res 2018; 14:46. [PMID: 29433483 PMCID: PMC5810121 DOI: 10.1186/s12917-018-1352-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 01/16/2018] [Indexed: 11/17/2022] Open
Abstract
Background Contagious mastitis is an important disease in dairy cattle, and the causative agent S. aureus can also impair raw milk cheese quality. In a confined region in eastern Switzerland attitude, knowledge and behaviour towards S. aureus und S. aureus control was assessed in 90 dairy farmers with communal alpine pasturing including raw milk cheese production with the aid of a questionnaire. Results Forty-three out of 90 questionnaires were returned (48% return rate). Farmers perceived reproductive problems as most important in their dairy herds followed by respiratory disease and diarrhoea in young stock. Most frequently stated as important motivating factors to participate in S. aureus control were “avoiding negative news about cheese quality in the press” followed by “I want to be proud of my somatic cell counts again”. Most frequently chosen and identified as important constraining factors were “I fear that the authorities dictate and the farmers are not heard” followed by “costs to control S. aureus are too high because of premature culling” and “I am afraid to be forced to cull genetically valuable cows”. Farmers with an experience of a S. aureus problem in their dairy herds had a significantly better knowledge about contagiosity and clinical manifestation of different S. aureus genotypes than farmers with no self-reported experience of a S. aureus problem. Veterinarians were indicated as the most important experts, farmers seek advice in case of mastitis and most farmers suggested subsidising bacteriological milk analysis as an incentive to motivate farmers towards S. aureus control. Conclusion According to the results an improved knowledge transfer on S. aureus to dairy producers and an integrative approach to a S. aureus control program with subsidising milk analysis will be most promising to improve the S. aureus situation in this confinded region of eastern Switzerland. Veterinarians should cover a key role in consulting farmers during the control program. Electronic supplementary material The online version of this article (10.1186/s12917-018-1352-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marie-Eve Cousin
- Epidemiology, Biostatistics and Prevention Institute, University of Zürich, Hirschengraben 84, 8001, Zürich, Switzerland
| | - Maria Christina Härdi-Landerer
- Institute of agricultural science, Animal Physiology, Swiss Federal Institute of Technology (ETH), Universitätsstrasse 2, 8092, Zürich, Switzerland
| | - Verena Völk
- Tierarztpraxis Dr. med. vet. Markus Nydegger, Scherlihalde 5, 3145, Niederscherli, Switzerland
| | - Michèle Bodmer
- Clinic for Ruminants, Vetsuisse-Faculty, University of Bern, Bremgartenstrasse 109a, 3001, Bern, Switzerland.
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10
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Thiran E, Di Ciccio P, Graber H, Zanardi E, Ianieri A, Hummerjohann J. Biofilm formation of Staphylococcus aureus dairy isolates representing different genotypes. J Dairy Sci 2018; 101:1000-1012. [DOI: 10.3168/jds.2017-13696] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 09/22/2017] [Indexed: 02/03/2023]
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11
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Rainard P, Foucras G, Fitzgerald JR, Watts JL, Koop G, Middleton JR. Knowledge gaps and research priorities in Staphylococcus aureus mastitis control. Transbound Emerg Dis 2017; 65 Suppl 1:149-165. [PMID: 28984427 DOI: 10.1111/tbed.12698] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Indexed: 12/31/2022]
Abstract
This study assessed knowledge gaps and suggested research priorities in the field of Staphylococcus aureus mastitis. Staphylococcus aureus infecting the mammary gland remains a major problem to the dairy industry worldwide because of its pathogenicity, contagiousness, persistence in the cow environment, colonization of skin or mucosal epithelia, and the poor curing efficacy of treatments. Staphylococcus aureus also constitutes a threat to public health due to food safety and antibiotic usage issues and the potential for bidirectional transmission of strains between humans and dairy animals (cows and small ruminants). Gaps have been identified in (i) understanding the molecular basis for pathogenesis of S. aureus mastitis, (ii) identifying staphylococcal antigens inducing protection and (iii) determining the cell-mediated immune responses to infection and vaccination. The recommended priorities for research are (i) improved diagnostic methods for early detection of infection and intervention through treatment or management, (ii) development of experimental models to investigate the strategies used by S. aureus to survive within the mammary gland and resist treatment with anti-microbials, (iii) investigation of the basis for cow-to-cow variation in response to S. aureus mastitis, (iv) identification of the immune responses (adaptive and innate) induced by infection or vaccination and (v) antibacterial discovery programmes to develop new, more effective, narrow spectrum antibacterial agents for the treatment of S. aureus mastitis. With the availability and ongoing improvement of molecular research tools, these objectives may not be out of reach in the future.
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Affiliation(s)
- P Rainard
- ISP, INRA, Université de Tours, UMR1282, Nouzilly, France
| | - G Foucras
- IHAP, Université de Toulouse, INRA, ENVT, Toulouse, France
| | - J R Fitzgerald
- The Roslin Institute, University of Edinburgh, Edinburgh, UK
| | - J L Watts
- Zoetis, External Innovation-Anti-Infectives, VMRD, Kalamazoo, MI, USA
| | - G Koop
- Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - J R Middleton
- Department of Veterinary Medicine and Surgery, University of Missouri, Columbia, MO, USA
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12
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Sartori C, Boss R, Ivanovic I, Graber HU. Development of a new real-time quantitative PCR assay for the detection of Staphylococcus aureus genotype B in cow milk, targeting the new gene adlb. J Dairy Sci 2017; 100:7834-7845. [PMID: 28755929 DOI: 10.3168/jds.2017-12820] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/02/2017] [Indexed: 01/15/2023]
Abstract
The specific and reliable diagnosis of mastitis pathogens is essential for successful sanitation programs. The aim of the present study was to develop and evaluate a new real-time quantitative PCR (qPCR) assay for the very sensitive and specific detection of Staphylococcus aureus genotype B in cow milk samples. This mastitis pathogen is contagious and particularly prevalent in Switzerland and other central European countries. The new test is based on a rapid preparation of bacteria, followed by DNA isolation and qPCR for a unique target gene coding for the adhesion-like bovine protein (adlb). The inclusivity of the new target gene was 97% and the exclusivity 98%, meaning that other genotypes and bacterial species could be excluded with high reliability. The limit of detection of the new assay was 235 staphylococcal cell equivalents/mL of culture. The new test shows high intra- and interassay repeatability. Results are available within 2 d after sampling, allowing farmers and veterinarians to apply sanitation measures immediately. Based on the results of a preliminary field study, the diagnostic sensitivity and specificity of the new qPCR assay are 99 and 100%, respectively. The new analytical procedure is straightforward and can be applied for routine diagnostics.
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Affiliation(s)
- C Sartori
- Agroscope, Food Microbial Systems, Group Microbiological Safety of Foods of Animal Origin, 3003 Berne, Switzerland; Animal Physiology Group, ETH Zurich, Institute of Agricultural Sciences (IAS), 8092 Zurich, Switzerland
| | - R Boss
- Agroscope, Food Microbial Systems, Group Microbiological Safety of Foods of Animal Origin, 3003 Berne, Switzerland; Federal Food Safety and Veterinary Office, 3003 Berne, Switzerland
| | - I Ivanovic
- Agroscope, Food Microbial Systems, Group Microbiological Safety of Foods of Animal Origin, 3003 Berne, Switzerland
| | - H U Graber
- Agroscope, Food Microbial Systems, Group Microbiological Safety of Foods of Animal Origin, 3003 Berne, Switzerland.
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13
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van den Borne BHP, Graber HU, Voelk V, Sartori C, Steiner A, Haerdi-Landerer MC, Bodmer M. A longitudinal study on transmission of Staphylococcus aureus genotype B in Swiss communal dairy herds. Prev Vet Med 2016; 136:65-68. [PMID: 27890338 DOI: 10.1016/j.prevetmed.2016.11.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/04/2016] [Accepted: 11/15/2016] [Indexed: 10/20/2022]
Abstract
Staphylococcus aureus is a common mastitis causing pathogen of dairy cattle. Several S. aureus genotypes exist, of which genotype B (GTB) is highly prevalent in Swiss dairy herds. Dairy farming in mountainous regions of Switzerland is characterised by the movement of dairy cattle to communal pasture-based operations at higher altitudes. Cows from different herds of origin share pastures and milking equipment for a period of 2 to 3 months during summer. The aim of this longitudinal observational study was to quantify transmission of S. aureus GTB in communal dairy operations. Cows (n=551) belonging to 7 communal operations were sampled at the beginning and end of the communal period. Transmission parameter β was estimated using a Susceptible-Infectious-Susceptible (SIS) model. The basic reproduction ratio R0 was subsequently derived using previously published information about the duration of infection. Mean transmission parameter β was estimated to be 0.0232 (95% CI: 0.0197-0.0274). R0 was 2.6 (95% CI: 2.2-3.0), indicating that S. aureus GTB is capable of causing major outbreaks in Swiss communal dairy operations. This study emphasized the contagious behaviour of S. aureus GTB. Mastitis management in communal dairy operations should be optimized to reduce S. aureus GTB transmission between cows and back to their herds of origin.
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Affiliation(s)
- Bart H P van den Borne
- Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, Schwarzenburgstrasse 151, 3097 Liebefeld, Switzerland.
| | - Hans U Graber
- Agroscope, Institute for Food Sciences, Schwarzenburgstrasse 161, 3003 Bern, Switzerland
| | - Verena Voelk
- Clinic for Ruminants, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3012 Bern, Switzerland
| | - Carlotta Sartori
- Agroscope, Institute for Food Sciences, Schwarzenburgstrasse 161, 3003 Bern, Switzerland
| | - Adrian Steiner
- Clinic for Ruminants, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3012 Bern, Switzerland
| | | | - Michèle Bodmer
- Clinic for Ruminants, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bremgartenstrasse 109a, 3012 Bern, Switzerland
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14
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Bludau MJ, Maeschli A, Leiber F, Klocke P, Berezowski JA, Bodmer M, Vidondo B. The influence of the rearing period on intramammary infections in Swiss dairy heifers: A cross-sectional study. Prev Vet Med 2016; 129:23-34. [PMID: 27317320 DOI: 10.1016/j.prevetmed.2016.04.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 04/19/2016] [Accepted: 04/25/2016] [Indexed: 11/29/2022]
Abstract
Healthy replacement heifers are one of the foundations of a healthy dairy herd. Farm management and rearing systems in Switzerland provide a wide variety of factors that could potentially be associated with intramammary infections (IMI) in early lactating dairy heifers. In this study, IMI with minor mastitis pathogens such as coagulase-negative staphylococci (CNS), contagious pathogens, and environmental major pathogens were identified. Fifty-four dairy farms were enrolled in the study. A questionnaire was used to collect herd level data on housing, management and welfare of young stock during farm visits and interviews with the farmers. Cow-level data such as breed, age at first calving, udder condition and swelling, and calving ease were also recorded. Data was also collected about young stock that spent a period of at least 3 months on an external rearing farm or on a seasonal alpine farm. At the quarter level, teat conditions such as teat lesions, teat dysfunction, presence of a papilloma and teat length were recorded. Within 24h after parturition, samples of colostral milk from 1564 quarters (391 heifers) were collected aseptically for bacterial culture. Positive bacteriological culture results were found in 49% of quarter samples. Potential risk factors for IMI were identified at the quarter, animal and herd level using multivariable and multilevel logistic regression analysis. At the herd level tie-stalls, and at cow-level the breed category "Brown cattle" were risk factors for IMI caused by contagious major pathogens such as Staphylococcus aureus (S. aureus). At the quarter-level, teat swelling and teat lesions were highly associated with IMI caused by environmental major pathogens. At the herd level heifer rearing at external farms was associated with less IMI caused by major environmental pathogens. Keeping pregnant heifers in a separate group was negatively associated with IMI caused by CNS. The odds of IMI with coagulase-negative staphylococci increased if weaning age was less than 4 months and if concentrates were fed to calves younger than 2 weeks. This study identified herd, cow- and quarter-level risk factors that may be important for IMI prevention in the future.
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Affiliation(s)
- M J Bludau
- Department of Livestock Science, Research Institute of Organic Agriculture (FiBL), Ackerstrasse 113, 5070 Frick, Switzerland
| | - A Maeschli
- Department of Livestock Science, Research Institute of Organic Agriculture (FiBL), Ackerstrasse 113, 5070 Frick, Switzerland
| | - F Leiber
- Department of Livestock Science, Research Institute of Organic Agriculture (FiBL), Ackerstrasse 113, 5070 Frick, Switzerland
| | - P Klocke
- Department of Livestock Science, Research Institute of Organic Agriculture (FiBL), Ackerstrasse 113, 5070 Frick, Switzerland
| | - J A Berezowski
- Veterinary Public Health Institute, University of Bern, Schwarzenburgstrasse 155, 3097 Liebefeld, Switzerland
| | - M Bodmer
- Clinic for Ruminants, University of Bern, Bremgartenstrasse 109a, 3012 Bern, Switzerland.
| | - B Vidondo
- Veterinary Public Health Institute, University of Bern, Schwarzenburgstrasse 155, 3097 Liebefeld, Switzerland
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15
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Stebler N, Schuepbach-Regula G, Braam P, Falzon LC. Weighting of Criteria for Disease Prioritization Using Conjoint Analysis and Based on Health Professional and Student Opinion. PLoS One 2016; 11:e0151394. [PMID: 26967655 PMCID: PMC4788351 DOI: 10.1371/journal.pone.0151394] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 02/26/2016] [Indexed: 11/18/2022] Open
Abstract
Disease prioritization exercises have been used by several organizations to inform surveillance and control measures. Though most methodologies for disease prioritization are based on expert opinion, it is becoming more common to include different stakeholders in the prioritization exercise. This study was performed to compare the weighting of disease criteria, and the consequent prioritization of zoonoses, by both health professionals and students in Switzerland using a Conjoint Analysis questionnaire. The health professionals comprised public health and food safety experts, cantonal physicians and cantonal veterinarians, while the student group comprised first-year veterinary and agronomy students. Eight criteria were selected for this prioritization based on expert elicitation and literature review. These criteria, described on a 3-tiered scale, were evaluated through a choice-based Conjoint Analysis questionnaire with 25 choice tasks. Questionnaire results were analyzed to obtain importance scores (for each criterion) and mean utility values (for each criterion level), and the latter were then used to rank 16 zoonoses. While the most important criterion for both groups was “Severity of the disease in humans”, the second ranked criteria by the health professionals and students were “Economy” and “Treatment in humans”, respectively. Regarding the criterion “Control and Prevention”, health professionals tended to prioritize a disease when the control and preventive measures were described to be 95% effective, while students prioritized a disease if there were almost no control and preventive measures available. Bovine Spongiform Encephalopathy was the top-ranked disease by both groups. Health professionals and students agreed on the weighting of certain criteria such as “Severity” and “Treatment of disease in humans”, but disagreed on others such as “Economy” or “Control and Prevention”. Nonetheless, the overall disease ranking lists were similar, and these may be taken into consideration when making future decisions regarding resource allocation for disease control and prevention in Switzerland.
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Affiliation(s)
- Nadine Stebler
- Veterinary Public Health Institute, University of Bern, Liebefeld, Switzerland
| | | | - Peter Braam
- Federal Food Safety and Veterinary Office, Liebefeld, Switzerland
| | - Laura Cristina Falzon
- Veterinary Public Health Institute, University of Bern, Liebefeld, Switzerland
- * E-mail:
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16
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Ciolacu L, Stessl B, Bolocan AS, Oniciuc EA, Wagner M, Rychli K, Nicolau AI. Tracking Foodborne Pathogenic Bacteria in Raw and Ready-to-Eat Food Illegally Sold at the Eastern EU Border. Foodborne Pathog Dis 2016; 13:148-55. [PMID: 26741503 DOI: 10.1089/fpd.2015.2057] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Food illegally brought into the European Union, mainly in the personal luggage of travelers, represents a potential threat to consumers' health. The aim of this study was to investigate the presence of five pathogens in food brought into the European Union by Moldavian citizens as personal goods and illegally sold in Romania in the vicinity of the border. The occurrence of Staphylococcus aureus and Listeria monocytogenes was 7.5% and 8%, while Campylobacter spp., Escherichia coli O157:H7, and Salmonella spp. were absent in all samples. L. monocytogenes sequence type 2, 9, 121, and 155, highly prevalent among foodstuffs worldwide, was also present among isolates from ready-to-eat food illegally sold in Romania, even at the same date of sampling, indicating cross-contamination during food handling. S. aureus spa types t449, t304, and t524 were most often isolated from raw-milk cheeses contaminated with 10(3)-10(5) colony-forming units per gram, evidencing a contamination at herd level or unhygienic conditions during processing. S. aureus t011 and t3625, both included in the livestock-associated CC398, were isolated from pork lard and poultry meat. This study shows that cross-border trade from nonmember states represents a neglected route of transmission of foodborne pathogens into the European Union that could lead to sporadic or family-associated cases of disease.
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Affiliation(s)
- Luminita Ciolacu
- 1 Faculty of Food Science and Engineering, Dunarea de Jos University of Galati , Galati, Romania .,2 Institute for Milk Hygiene, University of Veterinary Medicine Vienna , Vienna, Austria
| | - Beatrix Stessl
- 2 Institute for Milk Hygiene, University of Veterinary Medicine Vienna , Vienna, Austria
| | - Andrei Sorin Bolocan
- 1 Faculty of Food Science and Engineering, Dunarea de Jos University of Galati , Galati, Romania
| | - Elena Alexandra Oniciuc
- 1 Faculty of Food Science and Engineering, Dunarea de Jos University of Galati , Galati, Romania
| | - Martin Wagner
- 2 Institute for Milk Hygiene, University of Veterinary Medicine Vienna , Vienna, Austria
| | - Kathrin Rychli
- 2 Institute for Milk Hygiene, University of Veterinary Medicine Vienna , Vienna, Austria
| | - Anca Ioana Nicolau
- 1 Faculty of Food Science and Engineering, Dunarea de Jos University of Galati , Galati, Romania
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17
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Assis BS, Germon P, Silva AM, Even S, Nicoli JR, Le Loir Y. Lactococcus lactis V7 inhibits the cell invasion of bovine mammary epithelial cells by Escherichia coli and Staphylococcus aureus. Benef Microbes 2015; 6:879-86. [PMID: 26322541 DOI: 10.3920/bm2015.0019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Bovine mastitis, an inflammatory disease of the mammary gland often associated to bacterial infection, is the first cause of antibiotic use in dairy cattle. Because of the risk of antibioresistance emergence, alternative non-antibiotic strategies are needed to prevent or to cure bovine mastitis and reduce the antibiotic use in veterinary medicine. In this work, we investigated Lactococcus lactis V7, a strain isolated from the mammary gland, as a probiotic option against bovine mastitis. Using bovine mammary epithelial cell (bMEC) culture, and two representative strains for Escherichia coli and for Staphylococcus aureus, two major mastitis pathogens, we investigated L. lactis V7 ability to inhibit cell invasion (i.e. adhesion and internalization) of these pathogens into bMEC. L. lactis V7 ability to modulate the production of CXCL8, a key chemokine IL-8 responsible for neutrophil influx, in bMEC upon challenge with E. coli was investigated by an ELISA dosage of CXCL8 in bMEC culture supernatants. We showed that L. lactis V7 inhibited the internalisation of both E. coli and S. aureus strains into bMEC, whereas it inhibited the adhesion of only one out of the two S. aureus strains and of none of the E. coli strains tested. Investigation of the bMEC immune response showed that L. lactis V7 alone induced a slight increase in CXCL8 production in bMEC and that it increased the inflammatory response in bMEC challenged with the E. coli strains. Altogether these features of L. lactis V7 make it a potential promising candidate for a probiotic prevention strategy against bovine mastitis.
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Affiliation(s)
- B Seridan Assis
- 1 INRA, UMR 1253 STLO, 65 rue de Saint Brieuc, 35042 Rennes, France.,2 Agrocampus Ouest, UMR1253 STLO, 85 rue de Saint Brieuc, 35042 Rennes, France.,3 Departamento de Microbiologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270901, Brazil
| | - P Germon
- 4 INRA, UMR 1282 Infectiologie et Santé Publique, 37380 Nouzilly, France.,5 Université François Rabelais de Tours, UMR1282, Infectiologie et Santé Publique, 37000 Tours, France
| | - A M Silva
- 6 Departamento de Engenharia de Alimentos - Campus Sete Lagoas, Universidade Federal de São João del-Rey, Sete Lagoas, MG 36307-352, Brazil
| | - S Even
- 1 INRA, UMR 1253 STLO, 65 rue de Saint Brieuc, 35042 Rennes, France.,2 Agrocampus Ouest, UMR1253 STLO, 85 rue de Saint Brieuc, 35042 Rennes, France
| | - J R Nicoli
- 3 Departamento de Microbiologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270901, Brazil
| | - Y Le Loir
- 1 INRA, UMR 1253 STLO, 65 rue de Saint Brieuc, 35042 Rennes, France.,2 Agrocampus Ouest, UMR1253 STLO, 85 rue de Saint Brieuc, 35042 Rennes, France
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18
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Cremonesi P, Pozzi F, Raschetti M, Bignoli G, Capra E, Graber HU, Vezzoli F, Piccinini R, Bertasi B, Biffani S, Castiglioni B, Luini M. Genomic characteristics of Staphylococcus aureus strains associated with high within-herd prevalence of intramammary infections in dairy cows. J Dairy Sci 2015; 98:6828-38. [PMID: 26233457 DOI: 10.3168/jds.2014-9074] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 06/09/2015] [Indexed: 11/19/2022]
Abstract
Staphylococcus aureus is one of the most important causes of mastitis in dairy cattle. Based on previous research, Staph. aureus genotypes with different pathogenic and contagious properties can cause intramammary infection (IMI) and coexist in the same herd. Our study aimed to compare Staph. aureus strains from herds that differed in IMI prevalence using different molecular approaches such as ribosomal spacer (RS)-PCR, multilocus sequence typing (MLST), spa typing, ribotyping, pulsed-field gel electrophoresis (PFGE), and multiplex PCR. For this purpose, 31 dairy herds with Staph. aureus IMI were selected, and 16 of these were chosen for a comparison study: the 8 high-prevalence (HP) herds had Staph. aureus IMI prevalence >28% and the 8 low-prevalence (LP) herds had an IMI prevalence <4%. A total of 650 isolates of Staph. aureus from mammary quarters of all positive cows were genotyped with RS-PCR, a technique based on amplification of a portion of the intergenic spacer 16S-23S rRNA, and a subset of 54 strains was also analyzed by multiplex PCR, ribotyping, PFGE, MLST, and spa typing. The RS-PCR analysis revealed 12 different profiles. Staphylococcus aureus strains isolated from 5 out of 8 HP herds showed a profile identical to the genotype B (GTB), described in previous studies as being strongly associated with high within-herd prevalence of Staph. aureus mastitis and the presence of the genes coding for enterotoxins sea, sed, and sej, a long x-region of spa gene, and 3 lukE fragments. Moreover, all strains isolated in the HP herds possessed genes coding for staphylococcal enterotoxins. In LP herds, a limited number of strains of 6 genotypes, different from those isolated in HP herds, were identified and GTB was not found. Within these genotypes, 4 strains were positive for the mecA gene. Preliminary results and comparison with other genotyping methods confirmed that genotyping by RS-PCR is an accurate, rapid, and inexpensive tool for future field studies on Staph. aureus mastitis strains and generates clinically relevant results.
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Affiliation(s)
- P Cremonesi
- Istituto di Biologia e Biotecnologia Agraria, CNR, via Einstein, 26900 Lodi, Italy
| | - F Pozzi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia, Sezione di Lodi, via Einstein, 26900 Lodi, Italy
| | - M Raschetti
- Istituto di Biologia e Biotecnologia Agraria, CNR, via Einstein, 26900 Lodi, Italy
| | - G Bignoli
- Istituto di Biologia e Biotecnologia Agraria, CNR, via Einstein, 26900 Lodi, Italy
| | - E Capra
- Istituto di Biologia e Biotecnologia Agraria, CNR, via Einstein, 26900 Lodi, Italy
| | - H U Graber
- Agroscope, Institute for Food Sciences (IFS), Schwarzenburgstrasse 161, CH-3003, Bern, Switzerland
| | - F Vezzoli
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia, Sezione di Lodi, via Einstein, 26900 Lodi, Italy
| | - R Piccinini
- Dipartimento di Scienze Veterinarie e Sanità Pubblica, Università degli Studi di Milano, via Celoria, 20133 Milan, Italy
| | - B Bertasi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia, Reparto Tecnologie Acidi Nucleici Applicate agli Alimenti, via Bianchi, 25124 Brescia, Italy
| | - S Biffani
- Istituto di Biologia e Biotecnologia Agraria, CNR, via Einstein, 26900 Lodi, Italy; Parco Tecnologico Padano, Via Einstein, 26900 Lodi, Italy
| | - B Castiglioni
- Istituto di Biologia e Biotecnologia Agraria, CNR, via Einstein, 26900 Lodi, Italy
| | - M Luini
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia, Sezione di Lodi, via Einstein, 26900 Lodi, Italy.
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19
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Schärrer S, Widgren S, Schwermer H, Lindberg A, Vidondo B, Zinsstag J, Reist M. Evaluation of farm-level parameters derived from animal movements for use in risk-based surveillance programmes of cattle in Switzerland. BMC Vet Res 2015; 11:149. [PMID: 26170195 PMCID: PMC4499910 DOI: 10.1186/s12917-015-0468-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 07/06/2015] [Indexed: 11/25/2022] Open
Abstract
Background This study focused on the descriptive analysis of cattle movements and farm-level parameters derived from cattle movements, which are considered to be generically suitable for risk-based surveillance systems in Switzerland for diseases where animal movements constitute an important risk pathway. Methods A framework was developed to select farms for surveillance based on a risk score summarizing 5 parameters. The proposed framework was validated using data from the bovine viral diarrhoea (BVD) surveillance programme in 2013. Results A cumulative score was calculated per farm, including the following parameters; the maximum monthly ingoing contact chain (in 2012), the average number of animals per incoming movement, use of mixed alpine pastures and the number of weeks in 2012 a farm had movements registered. The final score for the farm depended on the distribution of the parameters. Different cut offs; 50, 90, 95 and 99 %, were explored. The final scores ranged between 0 and 5. Validation of the scores against results from the BVD surveillance programme 2013 gave promising results for setting the cut off for each of the five selected farm level criteria at the 50th percentile. Restricting testing to farms with a score ≥ 2 would have resulted in the same number of detected BVD positive farms as testing all farms, i.e., the outcome of the 2013 surveillance programme could have been reached with a smaller survey. Conclusions The seasonality and time dependency of the activity of single farms in the networks requires a careful assessment of the actual time period included to determine farm level criteria. However, selecting farms in the sample for risk-based surveillance can be optimized with the proposed scoring system. The system was validated using data from the BVD eradication program. The proposed method is a promising framework for the selection of farms according to the risk of infection based on animal movements.
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Affiliation(s)
- Sara Schärrer
- Veterinary Public Health Institute (VPHI), Vetsuisse Faculty, University of Bern, Bern, Switzerland.
| | | | | | - Ann Lindberg
- National Veterinary Institute (SVA), Uppsala, Sweden.
| | - Beatriz Vidondo
- Veterinary Public Health Institute (VPHI), Vetsuisse Faculty, University of Bern, Bern, Switzerland.
| | - Jakob Zinsstag
- Swiss Tropical and Public Health Institute (Swiss TPH), University of Basel, Basel, Switzerland.
| | - Martin Reist
- Federal Food Safety and Veterinary Office (FSVO), Bern, Switzerland.
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Tschopp A, Reist M, Kaufmann T, Bodmer M, Kretzschmar L, Heiniger D, Berchtold B, Wohlfender F, Harisberger M, Boss R, Strabel D, Cousin ME, Graber H, Steiner A, van den Borne B. A multiarm randomized field trial evaluating strategies for udder health improvement in Swiss dairy herds. J Dairy Sci 2015; 98:840-60. [DOI: 10.3168/jds.2014-8053] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 09/30/2014] [Indexed: 01/09/2023]
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21
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Guccione J, Cosandey A, Pesce A, Di Loria A, Pascale M, Piantedosi D, Steiner A, Graber H, Ciaramella P. Clinical outcomes and molecular genotyping of Staphylococcus aureus isolated from milk samples of dairy primiparous Mediterranean buffaloes (Bubalus bubalis). J Dairy Sci 2014; 97:7606-13. [DOI: 10.3168/jds.2014-8455] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 09/10/2014] [Indexed: 01/17/2023]
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