Evaluation of virulence factors profiles and antimicrobials resistance of Escherichia coli isolated from bulk tank milk and raw milk filters

2019 ◽  
Vol 123 ◽  
pp. 77-83 ◽  
Author(s):  
Francesca Dell'Orco ◽  
Claudia Gusmara ◽  
Monica Loiacono ◽  
Theo Gugliotta ◽  
Francesca Albonico ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Factors ◽  
Raw Milk ◽  
Bulk Tank Milk ◽  
Bulk Tank

scholarly journals The examination of presumed Escherichia coli count of raw milk samples on several milk production farms

2006 ◽  
pp. 31-37
Author(s):  
Ferenc Peles ◽  
András Szabó ◽  
Béla Béri ◽  
Péter Keresztúri
Keyword(s):  
Escherichia Coli ◽  
Raw Milk ◽  
Coliform Bacteria ◽  
Farm Size ◽  
Small Farms ◽  
Bulk Tank Milk ◽  
E Coli ◽  
Significant Difference ◽  
Bulk Tank ◽  
Large Farms

For dairy farms, it is of great importance to insure the appropriate hygienic status of milk and to examine it regularly. Escherichia coli, belonging to the coliform bacteria type of, is a good indicator of contamination, and therefore suitable for characterising the hygienic condition of milk production.The aim of our research was to examine the connection between the Escherichi coli count in bulk tank milk and housing and milking technologies of different-sizes farms. We examined the relation using various statistical methods.Analysing the connection between the E. coli count and the farm size we found no significant difference between the farms. On the basis of the mean values of the E. coli count, we can say that the hygienic conditions are appropriate for mid-sized farms, and tolerable for large farms. We found differences in the hygienic status among the small farms. Half of the eight small farms, had no adequate hygiene. The results of the analysis of the quality categories show that the probability of inadequate quality milk was the largest on small farms (37.5%).Comparing the various housing and milking methods with each other, there were numerical differences in the E. coli count, but these differences were not significant. We got higher E. coli count values on those farms using tied stall barn and bucket milking installation. The reason for this could be that in cases of farms using bucket milking installation, it is harder to meet the requirements.After forming groups by farm size, housing and milking methods, we found that the E. coli counts are adequate on mid-size farms using various housing and milking methods; and tolerable on those large farms using loose housing stable and a milking parlour. At the same time, we found inadequate E. coli counts on the smaller farms using tied stall barns and bucket milking installation.The results show that if there is suitable attention, independent of farm size, housing and milking procedure, it is possible to produce milk with low E. coli counts, and to insure appropriate hygienic conditions.Further detailed examinations are needed to decide which factors of housing and milking technologies influence the E. coli count of bulk tank milk.

Prevalence of Salmonella enterica, Listeria monocytogenes, and Escherichia coli Virulence Factors in Bulk Tank Milk and In-Line Filters from U.S. Dairies†

2011 ◽  
Vol 74 (5) ◽  
pp. 759-768 ◽  
Author(s):  
JO ANN S. VAN KESSEL ◽  
JEFFREY S. KARNS ◽  
JASON E. LOMBARD ◽  
CHRISTINE A. KOPRAL
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Real Time ◽  
Real Time Pcr ◽  
Salmonella Enterica ◽  
Raw Milk ◽  
The United States ◽  
Bulk Tank Milk ◽  
Milk Products ◽  
Bulk Tank

The zoonotic bacteria Salmonella enterica, Listeria monocytogenes, and Escherichia coli are known to infect dairy cows while not always causing clinical signs of disease. These pathogens are sometimes found in raw milk, and human disease outbreaks due to these organisms have been associated with the consumption of raw milk or raw milk products. Bulk tank milk (BTM) samples (536) and in-line milk filters (519) collected from dairy farms across the United States during the National Animal Health Monitoring System's Dairy 2007 study were analyzed by real-time PCR for the presence of S. enterica and pathogenic forms of E. coli and by culture techniques for the presence of L. monocytogenes. S. enterica was detected in samples from 28.1% of the dairy operations, primarily in milk filters. Salmonella was isolated from 36 of 75 PCR-positive BTM samples and 105 of 174 PCR-positive filter samples, and the isolates were serotyped. Cerro, Kentucky, Muenster, Anatum, and Newport were the most common serotypes. L. monocytogenes was isolated from 7.1% of the dairy operations, and the 1/2a complex was the most common serotype, followed by 1/2b and 4b (lineage 1). Shiga toxin genes were detected in enrichments from 15.2% of the BTM samples and from 51.0% of the filters by real-time PCR. In most cases, the cycle threshold values for the PCR indicated that toxigenic strains were not a major part of the enrichment populations. These data confirm those from earlier studies showing significant contamination of BTM by zoonotic bacterial pathogens and that the consumption of raw milk and raw milk products presents a health risk.

Occurrence and characterization of ciprofloxacin‐resistant Escherichia coli from bovine and ovine bulk tank milk samples in Turkey

2021 ◽  
Author(s):  
Cemil Kürekci ◽  
Muhsin Aydın ◽  
İbrahim Ozan Tekeli ◽  
Pınar Ambarcıoğlu ◽  
Seydi Ahmet Şengül ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Bulk Tank Milk ◽  
Milk Samples ◽  
Bulk Tank

Detection and Fate of Bacillus anthracis (Sterne) Vegetative Cells and Spores Added to Bulk Tank Milk†

2003 ◽  
Vol 66 (12) ◽  
pp. 2349-2354 ◽  
Author(s):  
MICHAEL L. PERDUE ◽  
JEFF KARNS ◽  
JIM HIGGINS ◽  
JO ANN VAN KESSEL
Keyword(s):  
Bacillus Anthracis ◽  
Protective Antigen ◽  
Lethal Factor ◽  
Raw Milk ◽  
Molecular Data ◽  
Molecular Techniques ◽  
Nucleotide Sequence Analysis ◽  
Vegetative Cells ◽  
Bulk Tank Milk ◽  
Bulk Tank

A preparation of Bacillus anthracis (Sterne strain) spores was used to evaluate commercially available reagents and portable equipment for detecting anthrax contamination by using real-time PCR and was used to assess the fate of spores added directly to bulk tank milk. The Ruggedized Advanced Pathogen Identification Device (RAPID) was employed to detect spores in raw milk down to a concentration of 2,500 spores per ml. Commercially available primers and probes developed to detect either the protective antigen gene or the lethal factor gene both provided easily read positive signals with the RAPID following extraction from milk with a commercially available DNA extraction kit. Nucleotide sequence analysis of the vrrA gene with the use of DNA extracted from spiked milk provided molecular data that readily identified the spores as B. anthracis with a 100% BLAST match to the Sterne and Ames strains and easily distinguished them from B. cereus. Physical-fate and thermal-stability studies demonstrated that spores and vegetative cells have a strong affinity for the cream fraction of whole milk. A single treatment at standard pasteurization temperatures, while 100% lethal to vegetative cells, had no effect on spore viability even 14 days after the treatment. Twenty-four hours after the first treatment, a second treatment at 72°C for 15 s reduced the viability of the population by ca. 99% but still did not kill all of the spores. From these studies, we conclude that standard pasteurization techniques for milk would have little effect on the viability of B. anthracis spores and that raw or pasteurized milk poses no obstacles to the rapid detection of the spores by molecular techniques.

Herd factors influencing free fatty acid concentrations in bulk tank milk

2019 ◽  
Vol 86 (2) ◽  
pp. 226-232 ◽  
Author(s):  
Lars Wiking ◽  
Martin Bjerring ◽  
Mette Marie Løkke ◽  
P. Løvendahl ◽  
T. Kristensen
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Production System ◽  
Onset Time ◽  
Raw Milk ◽  
Bulk Tank Milk ◽  
Bulk Milk ◽  
Milking Frequency ◽  
Technical Factors ◽  
Bulk Tank

AbstractFree fatty acid (FFA) concentrations can be elevated in raw milk due to improper handling and management at the dairy farm, and high concentrations of FFA can lead to off flavors in milk. This study aimed to describe how the herd production system, milking system, feeding and technological factors impact on FFA concentrations in bulk tank milk. FFA concentrations in bulk milk samples from 259 organic and 3326 conventional herds were analyzed by FT-IR during one year. The FFA content was significantly lower in bulk milk from organic than conventional herds. This was most evident during the summer half-year when the organic cows graze pasture. Bulk milk from automatic milking systems (AMS) and tie-stalls contained greater concentrations of FFA than any other milking parlor systems. In AMS, high milking frequency was found to be the most significant contributor to elevated FFA content in milk. Moreover, a strong interaction was found between milking interval and production system (organic vs. conventional). The technical factors, pre-cooling, onset time for cooling after milk inlet, contact between milk and agitation also impacted on the FFA concentration, whereas other technical factors including centrifugal pump type, length and height of pumping line and type of AMS manufacturer were found to be without significant effect on FFA. Feeding variables, based on feeding plans and evaluation, only explained a small part of the variation in bulk milk FFA. Overall, this study demonstrated that AMS compared to other milking system contributes significantly to increased FFA concentration in bulk tank milk, and within AMS high milking frequency contributes to increased FFA concentration.

Estimating Bacterial Pathogen Levels in New Zealand Bulk Tank Milk

2016 ◽  
Vol 79 (5) ◽  
pp. 771-780 ◽  
Author(s):  
J. C. MARSHALL ◽  
T. K. SOBOLEVA ◽  
P. JAMIESON ◽  
N. P. FRENCH
Keyword(s):  
New Zealand ◽  
Predictive Model ◽  
Pathogenic Bacteria ◽  
Fecal Contamination ◽  
Raw Milk ◽  
Quality Data ◽  
Bulk Tank Milk ◽  
E Coli ◽  
Cell Counts ◽  
Bulk Tank

ABSTRACT Zoonotic bacteria such as Campylobacter, Listeria, and Shiga toxin–producing Escherichia coli have been found in bulk tank milk in many countries, and the consumption of raw milk has been implicated in outbreaks of disease in New Zealand. Fecal contamination at milking is probably the most common source of pathogenic bacteria in bulk tank milk. Raw milk was collected from 80 New Zealand dairy farms during 2011 and 2012 and tested periodically for Campylobacter, E. coli O157, Listeria monocytogenes, and Salmonella. Milk quality data such as coliform counts, total bacterial counts, and somatic cell counts also were collected. By treating the total bacterial count as a proxy for fecal contamination of milk and utilizing farm and animal level prevalence and shedding rates of each pathogen, a predictive model for the level of pathogenic bacteria in bulk tank raw milk was developed. The model utilizes a mixture distribution to combine the low level of contamination inherent in the milking process with isolated contamination events associated with significantly higher pathogen levels. By simulating the sampling and testing process, the predictive model was validated against the observed prevalence of each pathogen in the survey. The predicted prevalence was similar to the observed prevalence for E. coli O157 and Salmonella, although the predicted prevalence was higher than that observed in samples tested for Campylobacter.

scholarly journals A new integrated approach to analyze bulk tank milk and raw milk filters for the presence of the E. coli serogroups frequently associated with VTEC status

2017 ◽  
Vol 115 ◽  
pp. 401-406 ◽  
Author(s):  
Francesca Albonico ◽  
Claudia Gusmara ◽  
Theo Gugliotta ◽  
Monica Loiacono ◽  
Michele Mortarino ◽  
...  
Keyword(s):  
Raw Milk ◽  
Integrated Approach ◽  
Bulk Tank Milk ◽  
E Coli ◽  
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.

scholarly journals Molecular characterization of Escherichia coli isolated from milk samples with regard to virulence factors and antibiotic resistance

2021 ◽  
pp. 2410-2418
Author(s):  
Waleed Younis ◽  
Sabry Hassan ◽  
Hams M. A. Mohamed
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
16S Rrna ◽  
Virulence Factors ◽  
Pathogenic Bacteria ◽  
Human Life ◽  
Raw Milk ◽  
Biochemical Tests ◽  
E Coli ◽  
Milk Samples

Background and Aim: Raw milk is considered an essential source of nutrition during all stages of human life because it offers a valuable supply of protein and minerals. Importantly, milk is considered a good media for the growth and contamination of many pathogenic bacteria, especially food-borne pathogens such as Escherichia coli. Thus, the objective of this study was to characterize E. coli and detect its virulence factors and antibiotic resistance from raw milk samples. Materials and Methods: Raw milk samples (n=100) were collected from different localities in Qena, Egypt, and investigated for the presence of E. coli using different biochemical tests, IMViC tests, serotyping to detect somatic antigen type, and molecularly by polymerase chain reaction (PCR) tests. The presence of different virulence and antimicrobial genes (hly, eae, stx1, stx2, blaTEM, tetA(A), and tetB genes) in E. coli isolates was evaluated using PCR. Results: The results demonstrated that 10 out of 100 milk samples were contaminated with E. coli. Depending on serology, the isolates were classified as O114 (one isolate), O27 (two isolates), O111 (one isolate), O125 (two isolates), and untypeable (five isolates) E. coli. The sequencing of partially amplified 16S rRNA of the untypeable isolates resulted in one isolate, which was initially misidentified as untypeable E. coli but later proved as Enterobacter hormaechei. Moreover, antibacterial susceptibility analysis revealed that nearly all isolates were resistant to more than 3 families of antibiotics, particularly to β-lactams, clindamycin, and rifampin. PCR results demonstrated that all E. coli isolates showed an accurate amplicon for the blaTEM and tetA(A) genes, four isolates harbored eae gene, other four harbored tetB gene, and only one isolate exhibited a positive stx2 gene. Conclusion: Our study explored vital methods for identifying E. coli as a harmful pathogen of raw milk using 16S rRNA sequencing, phylogenetic analysis, and detection of virulence factors and antibiotic-resistant genes.

Sign in / Sign up

Export Citation Format

Share Document