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Angelidis AS, Grammenou AS, Kotzamanidis C, Giadinis ND, Zdragas AG, Sergelidis D. Prevalence, Serotypes, Antimicrobial Resistance and Biofilm-Forming Ability of Listeria monocytogenes Isolated from Bulk-Tank Bovine Milk in Northern Greece. Pathogens 2023; 12:837. [PMID: 37375527 DOI: 10.3390/pathogens12060837] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
The prevalence of Listeria monocytogenes in bovine bulk-tank milk (BTM) in Greece has not been previously investigated. The aim of the study was to estimate the prevalence of L. monocytogenes in bovine BTM in Greece and to characterize the isolates in terms of carriage of genes encoding for pathogenic determinants, assess the isolates' biofilm-forming ability and determine their susceptibility against 12 antimicrobials. Samples (n = 138) of bovine BTM were obtained from farms located throughout Northern Greece and were analyzed qualitatively and quantitatively for L. monocytogenes. Five samples (3.6%) tested positive for L. monocytogenes. The pathogen's populations in these positive samples were below 5 CFU/mL. Most isolates belonged to the molecular serogroup "1/2a, 3a". All isolates carried the virulence genes inlA, inlC, inlJ, iap, plcA and hlyA, but actA was detected in only three isolates. The isolates displayed weak to moderate biofilm-forming ability and distinct antimicrobial resistance profiles. All isolates were characterized as multidrug resistant, with resistance to penicillin and clindamycin being a common feature. Considering that L. monocytogenes constitutes a serious public health threat, the key findings of the study, related to the carriage of virulence genes and multidrug resistance, highlight the importance of continued monitoring of the pathogen in farm animals.
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Affiliation(s)
- Apostolos S Angelidis
- Laboratory of Safety and Quality of Milk and Dairy Products, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Afroditi S Grammenou
- Laboratory of Hygiene of Foods of Animal Origin-Veterinary Public Health, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Charalampos Kotzamanidis
- Hellenic Agricultural Organization-DIMITRA, Veterinary Research Institute of Thessaloniki, 57001 Thermi, Greece
| | - Nektarios D Giadinis
- Clinic of Farm Animals, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece
| | - Antonios G Zdragas
- Hellenic Agricultural Organization-DIMITRA, Veterinary Research Institute of Thessaloniki, 57001 Thermi, Greece
| | - Daniel Sergelidis
- Laboratory of Hygiene of Foods of Animal Origin-Veterinary Public Health, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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2
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Sakaridis I, Psomas E, Karatzia MA, Samouris G. Hygiene and Safety of Hard Cheese Made from Raw Cows' Milk. Vet Sci 2022; 9:vetsci9100569. [PMID: 36288182 PMCID: PMC9609050 DOI: 10.3390/vetsci9100569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/22/2022] [Accepted: 10/12/2022] [Indexed: 11/05/2022] Open
Abstract
Simple Summary Raw cheeses have gained the preference of some consumers because of their intense and stronger taste compared with that of pasteurised cheeses. The pasteurization of raw milk causes the inactivation of the pathogenic and beneficial microorganisms of milk and of enzymes such as proteases and lipases which play a significant role in enhancing the unique flavour of raw cheeses. This study was conducted to evaluate the microbiological status of cheese made from unpasteurized cows’ milk, to examine the safety of the cheese and to observe the changes that occurred in its microbial community during ripening and storage. The microbiological quality of raw milk was found generally good and was improved throughout the experiments. For the cheese samples, a small increase in the prevalence of indicator microorganisms in curd and cheese samples was observed for the first few days, followed by a relatively stable condition as manufacturing proceeded and throughout the ripening of the final product. The outcome of our study was that the use of good-quality raw milk under sanitary conditions, the application of good manufacturing practices and a maturation period in a controlled environment were found to be the necessary prerequisites for the production of safe raw cheese products. Abstract This study was conducted to evaluate the microbiological status of cheese made from unpasteurized cows’ milk, to examine the safety of the cheese and to observe the changes that occurred in its microbial community during ripening and storage. Furthermore, the pH, the moisture and salt concentration were also monitored throughout processing, ripening and storage. Seven cheesemaking trials took place along with the microbiological and physicochemical analysis of the milk, curd and cheese produced. The milk used for the cheesemaking, two curd samples before the heating and two after the heating, two cheese samples at days 3, 7, 15, 30, 60 and 90 were subjected to microbiological analysis for total mesophilic bacterial count (for milk only), Enterobacteriaceae, E. coli, Staphylococcus, Salmonella, Listeria, and Clostridium. The microbiological quality of raw milk was found to be good. It was initially slightly above the EU limit but improvements associated with farm biosecurity and milking equipment hygiene led to a significantly improved milk quality. A small increase in the prevalence of indicator microorganisms in curd and cheese samples was observed for the first few days, followed by a relatively stable condition as manufacturing proceeded and throughout the ripening of the final product. In two cheesemaking trials, Clostridium perfringens and Salmonella spp. were detected, the first originating from the milk and the second from the environment. The use of good-quality raw milk under sanitary conditions, the application of good manufacturing practices and a maturation period in a controlled environment were found to be the necessary prerequisites for the production of safe raw cheese products.
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Affiliation(s)
- Ioannis Sakaridis
- Department of Hygiene and Technology of Food of Animal Origin, Veterinary Research Institute, Hellenic Agricultural Organization-Demeter, Campus of Thermi, 57001 Thessaloniki, Greece
- Correspondence:
| | - Evdoxios Psomas
- Department of Hygiene and Technology of Food of Animal Origin, Veterinary Research Institute, Hellenic Agricultural Organization-Demeter, Campus of Thermi, 57001 Thessaloniki, Greece
| | - Maria-Anastasia Karatzia
- Research Institute of Animal Science, Hellenic Agricultural Organization-Demeter, 58100 Giannitsa, Greece
| | - Georgios Samouris
- Department of Hygiene and Technology of Food of Animal Origin, Veterinary Research Institute, Hellenic Agricultural Organization-Demeter, Campus of Thermi, 57001 Thessaloniki, Greece
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3
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Bacterial Milk Quality along the Value Chain in Smallholder Dairy Production. ScientificWorldJournal 2022; 2022:7967569. [PMID: 36187286 PMCID: PMC9519332 DOI: 10.1155/2022/7967569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/05/2022] [Indexed: 11/18/2022] Open
Abstract
This study aimed to evaluate the microbial quality of raw milk along the milk value chain at Africa University (AU). Eighteen Holstein-Friesian cows were used in this experiment. A total of 270 milk samples were collected for laboratory analysis at three different stages, during milking (DM), from the bulk tank (BT), and at the dining hall (DH), to determine the total bacterial count (TBC), Escherichia coli, and Salmonella enterica. Samples were cultured in Petri dishes using an appropriate medium for 48 hours. The plate count method was used to determine the quantity of bacteria. Data were analyzed using GLM SPSS. The results indicated that TBC increased (
< 0.05) from one site to the next along the value chain, yet it undulates when measured over time. Escherichia. coli and S. enterica counts increased (
< 0.05) at the last site of collection and the highest counts were recorded in week two. In conclusion, the current study indicates the hygiene of the dairy parlor with very low TBC, E. coli, and S. enterica counts during milking and bulk tank storage and that the relationship between TBC and E. coli is nonlinear with respect to time.
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4
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Garbaj AM, Gawella TBB, Sherif JA, Naas HT, Eshamah HL, Azwai SM, Gammoudi FT, Abolghait SK, Moawad AA, Barbieri I, Eldaghayes IM. Occurrence and antibiogram of multidrug-resistant Salmonella enterica isolated from dairy products in Libya. Vet World 2022; 15:1185-1190. [PMID: 35765472 PMCID: PMC9210834 DOI: 10.14202/vetworld.2022.1185-1190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 03/21/2022] [Indexed: 11/16/2022] Open
Abstract
Background and Aim: Foodborne illnesses are a serious challenge to human health and the economic sector. For example, salmonellosis remains a burden in developed and developing nations. Rapid and reliable molecular methods to identify Salmonella strains are essential for minimizing human infection. This study aimed to identify Salmonella spp. in raw milk and dairy products using conventional and molecular techniques and to test the antibiotic susceptibility of the isolated strains.
Materials and Methods: One hundred and thirty-one milk and dairy product samples were randomly collected from different localities in Libya. Samples were examined for the presence of Salmonella by conventional culture techniques, including cultivation in Rappaport-Vassiliadis broth and streaking on xylose lysine deoxycholate agar. Identification also used polymerase chain reaction and partial sequencing of 16S rDNA. Twenty-four antibiotics were used for the examination of antimicrobial resistance of Salmonella spp. isolates with the agar disk diffusion method (Kirby–Bauer technique). Multi-antibiotic resistance index and antibiotic resistance index (ARI)for Salmonella enterica isolates were calculated.
Results: Twenty-one of 131 samples (16%) were positive for Salmonella spp. recovered from 9 (16%), 2 (11%), 4 (22.2%), and 6 (46%) samples of raw cow milk, fermented raw milk, and fresh locally made soft cheeses, Maasora and Ricotta), respectively. Samples of ice cream, milk powder, and infant formula showed no Salmonella spp. contamination. Only 9 of 21 (42.8%) isolates were confirmed as S. enterica by partial sequence 16S rDNA analysis. All isolates were resistant to amoxycillin, bacitracin, penicillin G, lincomycin, vancomycin, clindamycin, and cloxacillin with an ARI of 0.042. In contrast, all tested strains were sensitive to levofloxacin, doxycycline, and ciprofloxacin. In addition, all of the tested isolates (100%) were resistant to more than one antibiotic.
Conclusion: This study demonstrated the applicability of molecular techniques, compared with conventional methods, as preferable for the identification of Salmonella in milk and dairy products and thus reduction of milk-borne transmission to the consumers. From the view of public health, isolation and identification of Salmonella multidrug-resistant strains from raw cow's milk and locally prepared dairy products sold in the Libyan markets indicate the need to improve the handling and processing of milk and dairy products to minimize the prevalence of Salmonella, one of the most important foodborne microorganisms that cause food poisoning.
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Affiliation(s)
- Aboubaker M. Garbaj
- Department of Food Hygiene and Control, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
| | - Tahani B. Ben Gawella
- Department of Food Hygiene and Control, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
| | - Jihan A. Sherif
- Department of Food Hygiene and Control, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
| | - Hesham T. Naas
- Department of Food Hygiene and Control, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
| | - Hanan L. Eshamah
- Department of Food Hygiene and Control, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
| | - Salah M. Azwai
- Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
| | - Fatim T. Gammoudi
- Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
| | - Said K. Abolghait
- Department of Food Hygiene and Control, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Ashraf A. Moawad
- Department of Food Hygiene and Control, Faculty of Veterinary Medicine, Cairo University, 12211 Giza 12211, Egypt
| | - Ilaria Barbieri
- Department of Genetics, The Lombardy and Emilia Romagna Experimental Zootechnic Institute, Via Bianchi 9, Brescia 25124, Italy
| | - Ibrahim M. Eldaghayes
- Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya
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5
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Taghizadeh M, Nematollahi A, Bashiry M, Javanmardi F, Mousavil M, Hosseini H. The global prevalence of Campylobacter spp. in milk A systematic review and meta-analysis. Int Dairy J 2022. [DOI: 10.1016/j.idairyj.2022.105423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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6
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A European-wide dataset to uncover adaptive traits of Listeria monocytogenes to diverse ecological niches. Sci Data 2022; 9:190. [PMID: 35484273 PMCID: PMC9050667 DOI: 10.1038/s41597-022-01278-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 03/23/2022] [Indexed: 02/08/2023] Open
Abstract
Listeria monocytogenes (Lm) is a ubiquitous bacterium that causes listeriosis, a serious foodborne illness. In the nature-to-human transmission route, Lm can prosper in various ecological niches. Soil and decaying organic matter are its primary reservoirs. Certain clonal complexes (CCs) are over-represented in food production and represent a challenge to food safety. To gain new understanding of Lm adaptation mechanisms in food, the genetic background of strains found in animals and environment should be investigated in comparison to that of food strains. Twenty-one partners, including food, environment, veterinary and public health laboratories, constructed a dataset of 1484 genomes originating from Lm strains collected in 19 European countries. This dataset encompasses a large number of CCs occurring worldwide, covers many diverse habitats and is balanced between ecological compartments and geographic regions. The dataset presented here will contribute to improve our understanding of Lm ecology and should aid in the surveillance of Lm. This dataset provides a basis for the discovery of the genetic traits underlying Lm adaptation to different ecological niches. Measurement(s) | whole genome sequencing | Technology Type(s) | Illumina Sequencing | Factor Type(s) | Multi-locus sequence types • Geographic location • Animal associated environment isolates • Food product and food production environment isolates | Sample Characteristic - Organism | Listeria monocytogenes | Sample Characteristic - Environment | Farm • Ruminant • Agricultural soil • Wild animals • food processing building • dairy food product • meat or meat product (from mammal) (us cfr) • chicken meat food product • fish food product • vegetable or vegetable product (us cfr) | Sample Characteristic - Location | Europe |
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7
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Calahorrano-Moreno MB, Ordoñez-Bailon JJ, Baquerizo-Crespo RJ, Dueñas-Rivadeneira AA, B. S. M. Montenegro MC, Rodríguez-Díaz JM. Contaminants in the cow's milk we consume? Pasteurization and other technologies in the elimination of contaminants. F1000Res 2022; 11:91. [PMID: 35186276 PMCID: PMC8822143 DOI: 10.12688/f1000research.108779.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/19/2022] [Indexed: 11/30/2022] Open
Abstract
Cow's milk is currently the most consumed product worldwide. However, due to various direct and indirect contamination sources, different chemical and microbiological contaminants have been found in cow's milk. This review details the main contaminants found in cow's milk, referring to the sources of contamination and their impact on human health. A comparative approach highlights the poor efficacy and effects of the pasteurization process with other methods used in the treatment of cow's milk. Despite pasteurization and related techniques being the most widely applied to date, they have not demonstrated efficacy in eliminating contaminants. New technologies have appeared as alternative treatments to pasteurization. However, in addition to causing physicochemical changes in the raw material, their efficacy is not total in eliminating chemical contaminants, suggesting the need for new research to find a solution that contributes to improving food safety.
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Affiliation(s)
- Micaela Belen Calahorrano-Moreno
- Departamento de Procesos Químicos, Facultad de Ciencias Matemáticas, Físicas y Químicas, Universidad Técnica de Manabí, Portoviejo, Manabí, 130104, Ecuador
| | - Jonathan Jerry Ordoñez-Bailon
- Departamento de Procesos Químicos, Facultad de Ciencias Matemáticas, Físicas y Químicas, Universidad Técnica de Manabí, Portoviejo, Manabí, 130104, Ecuador
| | - Ricardo José Baquerizo-Crespo
- Departamento de Procesos Químicos, Facultad de Ciencias Matemáticas, Físicas y Químicas, Universidad Técnica de Manabí, Portoviejo, Manabí, 130104, Ecuador
| | - Alex Alberto Dueñas-Rivadeneira
- Departamento de Procesos Agroindustriales, Facultad de Ciencias Zootécnicas, Universidad Técnica de Manabí, Portoviejo, Manabí, 130104, Ecuador
| | | | - Joan Manuel Rodríguez-Díaz
- Departamento de Procesos Químicos, Facultad de Ciencias Matemáticas, Físicas y Químicas, Universidad Técnica de Manabí, Portoviejo, Manabí, 130104, Ecuador
- Laboratorio de Análisis Químicos y Biotecnológicos, Instituto de Investigación, Universidad Técnica de Manabí, Portoviejo, Manabí, 130104, Ecuador
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8
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Wemmenhove E, Wells-Bennik MHJ, Zwietering MH. A model to predict the fate of Listeria monocytogenes in different cheese types - A major role for undissociated lactic acid in addition to pH, water activity, and temperature. Int J Food Microbiol 2021; 357:109350. [PMID: 34455130 DOI: 10.1016/j.ijfoodmicro.2021.109350] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 07/20/2021] [Accepted: 07/24/2021] [Indexed: 10/20/2022]
Abstract
Undissociated lactic acid has been shown to play a major role in complete growth inhibition of Listeria monocytogenes in Gouda cheese. In addition, low water activity conditions may contribute to growth inhibition. In the current study, it was assessed whether the major factors that inhibit growth of L. monocytogenes in Gouda cheese are the factors that determine growth in other types of ready-to-eat cheese as well. Various types of cheeses were selected, some of which had been associated with listeriosis, while others had not. Based on the composition of the different cheese types, the concentrations of undissociated lactic acid were calculated for each type. The ability to support growth of L. monocytogenes was predicted using the Gamma model, based on literature data on total lactic acid content, moisture content, fat content, pH, Aw, and temperature, and optimal growth rates in milk at 30-37 °C. In addition, the actual specific growth rates of L. monocytogenes in the various cheeses were calculated based on available experimental growth data. In 9 out of the 10 RTE cheeses reviewed, the undissociated lactic acid concentrations and aw determined growth/no growth of L. monocytogenes. No growth was correctly predicted for feta, Cheddar and Gouda, and growth was correctly predicted for ricotta, queso fresco, Camembert, high-moisture mozzarella, cottage and blue cheese. Growth of L. monocytogenes was not observed in practice upon inoculation of Emmental, whereas growth in this cheese type was predicted when including the above mentioned factors in the models. Other factors, presumably acetic and propionic acid, are thought to be important to inhibit growth of the pathogen in Emmental. The results from our study show that for cheeses in which lactic acid is a main acid, our model based on undissociated lactic acid, temperature, pH and aw gives a good prediction of potential outgrowth of L. monocytogenes. Implications for L. monocytogenes legislation are discussed per type of RTE cheese reviewed.
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Affiliation(s)
- E Wemmenhove
- NIZO, Ede, the Netherlands; Food Microbiology, Wageningen University, the Netherlands
| | | | - M H Zwietering
- Food Microbiology, Wageningen University, the Netherlands.
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9
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Detection, virulence genes and antimicrobial resistance of Yersinia enterocolitica in sheep and goat raw milk. Int Dairy J 2021. [DOI: 10.1016/j.idairyj.2021.105011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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10
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Kürekci C, Aydın M, Tekeli İO, Ambarcıoğlu P, Şengül SA, Sakin F. Occurrence and characterization of ciprofloxacin‐resistant
Escherichia coli
from bovine and ovine bulk tank milk samples in Turkey. J Food Saf 2021. [DOI: 10.1111/jfs.12881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Cemil Kürekci
- Department of Food Hygiene and Technology, Faculty of Veterinary Medicine Mustafa Kemal University Antakya Hatay Turkey
| | - Muhsin Aydın
- Department of Biology, Faculty of Science and Letters Adıyaman University Adıyaman Turkey
| | - İbrahim Ozan Tekeli
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine Mustafa Kemal University Antakya Hatay Turkey
| | - Pınar Ambarcıoğlu
- Department of Biostatistics, Faculty of Veterinary Medicine Mustafa Kemal University Antakya Hatay Turkey
| | - Seydi Ahmet Şengül
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine Mustafa Kemal University Antakya Hatay Turkey
| | - Fatih Sakin
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine Mustafa Kemal University Antakya Hatay Turkey
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11
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Khalid DM, Abbas BA. Prevalence, antibiotic susceptibility, and virulence factors of Yersinia enterocolitica isolated from raw milk in Basrah, Iraq. BULGARIAN JOURNAL OF VETERINARY MEDICINE 2021. [DOI: 10.15547/bjvm.2019-0044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A total of one hundred and fifty cow, buffalo, and sheep milk samples were collected from several markets in Basrah, Iraq (50 samples from each species). All milk samples were subjected to enrichment in TSB and cold enrichment in PBS, then cultured on YSA agar in order to obtain Yersinia species. The highest growth obtained by TSB enrichment was seen in cow milk (24%) followed by buffalo milk (22%) and sheep milk (12%). The results of PBS enrichment showed the highest growth in cow milk (14%) followed by buffalo (8%) and sheep milk (2%). The results showed that both cow and buffalo milk samples were contaminated by Y. enterocolitica at 8% while the prevalence in sheep milk was 4%. Ten isolates from different sources in the current study were examined for their susceptibility to 10 antibiotics. The highest susceptibility (100%) was found towards streptomycin, azithromycin and gentamicin, followed by ciprofloxacin and chloramphenicol, 93.3% for each. Low susceptibility was found toward vancomycin (6.66%) and cloxacillin (33.3%). 16S rRNA sequencing showed homology with previously annotated strains at GenBank of National Centre for Biotechnology (NCBI). Multiple sequence alignments exhibited one difference between the sequences at the locus 764. The phylogenic tree of the results demonstrated that the local isolates were closely related to strains previously reported from China. All Yersinia enterocolitica strains had the inv gene. In contrast, the ail gene was found in one strain (10%) while the yad gene appeared in 50% of the investigated strains.
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12
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Shimojima Y, Kodo Y, Soeda K, Koike H, Kanda M, Hayashi H, Nishino Y, Fukui R, Kuroda S, Hirai A, Suzuki J, Sadamasu K. [Prevalence of Cereulide-Producing Bacillus cereus in Pasteurized Milk]. Food Hygiene and Safety Science (Shokuhin Eiseigaku Zasshi) 2020; 61:178-182. [PMID: 33132361 DOI: 10.3358/shokueishi.61.178] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
To recognize the risk of Bacillus cereus in pasteurized milk, we investigated the prevalence of B. cereus and the rate of the production of cereulide from B. cereus isolates. B. cereus was found in 66 out of 101 (65.3%) domestically pasteurized milk samples in Japan. The ces gene was identified in 3 out of 90 B. cereus isolates that were isolated from three samples (one product) among the 101 samples. The ces gene positive isolate, the reference strain F4810/72 and a B. cereus isolate collected in a food poisoning incident were shown the productivity of cereulide using an LC-MS/MS analysis. The LC-MS/MS analysis was confirmed the ability of identification and quantification of cereulide produced in the milk samples. In this study, it was shown that B. cereus strains are prevalent in pasteurized milk, some of these strains produce cereulide, and confirmed usefulness of LC-MS/MS analysis to detect cereulide in milk.
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Affiliation(s)
| | | | - Kana Soeda
- Tokyo Metropolitan Institute of Public Health
| | | | - Maki Kanda
- Tokyo Metropolitan Institute of Public Health
| | | | | | - Rie Fukui
- Tokyo Metropolitan Institute of Public Health
| | | | | | - Jun Suzuki
- Tokyo Metropolitan Institute of Public Health
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13
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Fusco V, Chieffi D, Fanelli F, Logrieco AF, Cho G, Kabisch J, Böhnlein C, Franz CMAP. Microbial quality and safety of milk and milk products in the 21st century. Compr Rev Food Sci Food Saf 2020; 19:2013-2049. [DOI: 10.1111/1541-4337.12568] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 04/03/2020] [Accepted: 04/03/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Vincenzina Fusco
- Institute of Sciences of Food Production National Research Council of Italy (CNR‐ISPA) Bari Italy
| | - Daniele Chieffi
- Institute of Sciences of Food Production National Research Council of Italy (CNR‐ISPA) Bari Italy
| | - Francesca Fanelli
- Institute of Sciences of Food Production National Research Council of Italy (CNR‐ISPA) Bari Italy
| | - Antonio F. Logrieco
- Institute of Sciences of Food Production National Research Council of Italy (CNR‐ISPA) Bari Italy
| | - Gyu‐Sung Cho
- Department of Microbiology and BiotechnologyMax‐Rubner Institut Kiel Germany
| | - Jan Kabisch
- Department of Microbiology and BiotechnologyMax‐Rubner Institut Kiel Germany
| | - Christina Böhnlein
- Department of Microbiology and BiotechnologyMax‐Rubner Institut Kiel Germany
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14
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Reduction in microbial infection risks from raw milk by Electron Beam Technology. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2019.108567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Use of indicator bacteria for monitoring sanitary quality of raw milk cheeses – A literature review. Food Microbiol 2020; 85:103283. [DOI: 10.1016/j.fm.2019.103283] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 06/06/2019] [Accepted: 07/30/2019] [Indexed: 11/17/2022]
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16
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Flink C, Nyberg K. Occurrence of
Campylobacter
spp.,
Salmonella
spp. and shiga toxin‐producing
Escherichia coli
in inline milk filters from Swedish dairy farms. J Food Saf 2019. [DOI: 10.1111/jfs.12726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Karin Nyberg
- Science Division, Swedish Food Agency Uppsala Sweden
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17
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Wuytack A, De Visscher A, Piepers S, Boyen F, Haesebrouck F, De Vliegher S. Non-aureus staphylococci in fecal samples of dairy cows: First report and phenotypic and genotypic characterization. J Dairy Sci 2019; 102:9345-9359. [PMID: 31421888 DOI: 10.3168/jds.2019-16662] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 05/28/2019] [Indexed: 01/30/2023]
Abstract
The aims of this study were to determine whether non-aureus staphylococci (NAS) are present in rectal feces of healthy dairy cows, and if so, to delineate species to which they belong and to study several phenotypic and genotypic traits as a first step toward determining the potential impact of fecal shedding of NAS on bovine udder health. Fecal samples were aseptically collected from the rectum of 25 randomly selected clinically healthy dairy cows in a commercial dairy herd using an automated milking system. Fecal NAS were isolated and then identified at the species level using transfer RNA-intergenic spacer PCR and sequencing of the 16S rRNA housekeeping gene. Strain typing was performed using random amplification of polymorphic DNA (RAPD)-PCR. The antimicrobial resistance profiles, biofilm formation, and growth and inhibitory characteristics of all NAS isolates were evaluated. Half of the cows were shedding NAS, resulting in 31 NAS isolates belonging to 11 different species. The most prevalent species were Staphylococcus rostri (23%, n = 7), Staphylococcus cohnii (16%, n = 5), and Staphylococcus haemolyticus (13%, n = 4) with all Staphylococcus agnetis, Staphylococcus chromogenes, and Staph. rostri isolates belonging to the same strain according to RAPD banding patterns. Acquired antimicrobial resistance was observed in 28 of the 31 NAS isolates, mainly due to β-lactamase production. Most of the isolates (84%, n = 27) had a weak biofilm-forming potential, but only 2 contained the bap gene. The ica and aap genes were not detected in any of the isolates. In vitro growth of Staphylococcus aureus and Streptococcus dysgalactiae was inhibited by Staph. agnetis isolates, and Staph. chromogenes isolates were able to inhibit the growth of Strep. dysgalactiae and Streptococcus uberis. All fecal isolates were able to grow when oxygen and iron were limitedly available, mimicking the growth conditions in the mammary gland.
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Affiliation(s)
- A Wuytack
- M-team and Mastitis and Milk Quality Research Unit, Department of Reproduction, Obstetrics, and Herd Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - A De Visscher
- Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Technology and Food Science, Agricultural Engineering, Burg. Van Gansberghelaan 115 bus 1, 9820 Merelbeke, Belgium
| | - S Piepers
- M-team and Mastitis and Milk Quality Research Unit, Department of Reproduction, Obstetrics, and Herd Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - F Boyen
- Department of Pathology, Bacteriology, and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - F Haesebrouck
- Department of Pathology, Bacteriology, and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - S De Vliegher
- M-team and Mastitis and Milk Quality Research Unit, Department of Reproduction, Obstetrics, and Herd Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium.
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18
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Leclair RM, McLean SK, Dunn LA, Meyer D, Palombo EA. Investigating the Effects of Time and Temperature on the Growth of Escherichia coli O157:H7 and Listeria monocytogenes in Raw Cow's Milk Based on Simulated Consumer Food Handling Practices. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E2691. [PMID: 31357682 PMCID: PMC6696089 DOI: 10.3390/ijerph16152691] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/15/2019] [Accepted: 07/24/2019] [Indexed: 11/16/2022]
Abstract
Consumption of raw cow's milk (RCM) is increasing in popularity in developed countries despite the associated foodborne disease risks. While previous research has focused on consumer motivations for drinking RCM, there is limited research on how consumer handling practices may impact the microbiological safety of RCM. In this study, consumer handling practices associated with transport, storage, and freezing and thawing were simulated to investigate the impact of time and temperature variables on the concentrations of either Escherichia coli O157:H7 or Listeria monocytogenes in RCM. We found that the type of storage during simulated transport had a large (η2 = 0.70) and significant (p < 0.001) effect on both pathogens. The refrigeration temperature also had a large (η2 = 0.43) and significant (p < 0.001) effect on both pathogens during refrigerated storage. The interaction between pathogen species and initial pathogen inoculum level had a large (η2 = 0.20) and significant (p = 0.012) effect on the concentration of the pathogens during ambient temperature storage. We found that freezing and thawing practices did not have a significant effect on the pathogens (p > 0.05). However, we were able to recover L. monocytogenes, but not E. coli O157:H7, from RCM after freezing for 365 days. The results from this study highlight that consumer transport and storage practices can have significant effects on the growth of E. coli O157:H7 and L. monocytogenes in RCM. Consumer food handling practices should be considered when developing public health strategies aimed at reducing the risks of RCM consumption.
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Affiliation(s)
- Roselyn M Leclair
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia.
| | - Sarah K McLean
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Louise A Dunn
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Denny Meyer
- Department of Statistics, Data Science and Epidemiology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Enzo A Palombo
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
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19
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Prevalence of Yersinia enterocolitica in milk and dairy products and the effects of storage temperatures on survival and virulence gene expression. Int Dairy J 2019. [DOI: 10.1016/j.idairyj.2019.02.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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20
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Castro H, Jaakkonen A, Hakakorpi A, Hakkinen M, Isidro J, Korkeala H, Lindström M, Hallanvuo S. Genomic Epidemiology and Phenotyping Reveal on-Farm Persistence and Cold Adaptation of Raw Milk Outbreak-Associated Yersinia pseudotuberculosis. Front Microbiol 2019; 10:1049. [PMID: 31156582 PMCID: PMC6528616 DOI: 10.3389/fmicb.2019.01049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 04/25/2019] [Indexed: 11/13/2022] Open
Abstract
Packaged raw milk contaminated with Yersinia pseudotuberculosis mediated a large yersiniosis outbreak in southern Finland in 2014. The outbreak was traced back to a single dairy farm in southern Finland. Here we explore risk factors leading to the outbreak through epidemiologic investigation of the outbreak farm and through genomic and phenotypic characterization of the farm’s outbreak and non-outbreak associated Y. pseudotuberculosis strains. We show that the outbreak strain persisted on the farm throughout the 7-month study, whereas the non-outbreak strains occurred sporadically. Phylogenomic analysis illustrated that the outbreak strain was related to previously published genomes of wild animal isolates from Finland, implying that wild animals were a potential source of the outbreak strain to the farm. We observed allelic differences between the farm’s outbreak and non-outbreak strains in several genes associated with virulence, stress response and biofilm formation, and found that the outbreak strain formed biofilm in vitro and maintained better growth fitness during cold stress than the non-outbreak strains. Finally, we demonstrate the rapid growth of the outbreak strain in packaged raw milk during refrigerated storage. This study provides insight of the risk factors leading to the Y. pseudotuberculosis outbreak, highlights the importance of pest control to avoid the spread of pathogens from wild to domestic animals, and demonstrates that the cold chain is insufficient as the sole risk management strategy to control Y. pseudotuberculosis risk associated with raw drinking milk.
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Affiliation(s)
- Hanna Castro
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Anniina Jaakkonen
- Microbiology Unit, Laboratory and Research Division, Finnish Food Authority, Helsinki, Finland
| | - Anna Hakakorpi
- Microbiology Unit, Laboratory and Research Division, Finnish Food Authority, Helsinki, Finland
| | - Marjaana Hakkinen
- Microbiology Unit, Laboratory and Research Division, Finnish Food Authority, Helsinki, Finland
| | - Joana Isidro
- National Reference Laboratory for Gastrointestinal Infections, Department of Infectious Diseases, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal.,Innovation and Technology Unit, Department of Human Genetics, National Institute of Health Dr. Ricardo Jorge, Lisbon, Portugal
| | - Hannu Korkeala
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Miia Lindström
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Saija Hallanvuo
- Microbiology Unit, Laboratory and Research Division, Finnish Food Authority, Helsinki, Finland
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Longitudinal Study of Shiga Toxin-Producing Escherichia coli and Campylobacter jejuni on Finnish Dairy Farms and in Raw Milk. Appl Environ Microbiol 2019; 85:AEM.02910-18. [PMID: 30709824 PMCID: PMC6585499 DOI: 10.1128/aem.02910-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 01/28/2019] [Indexed: 01/12/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) and Campylobacter jejuni are notable health hazards associated with the consumption of raw milk. These bacteria may colonize the intestines of asymptomatic cattle and enter bulk tank milk via fecal contamination during milking. We studied the frequency of STEC O157:H7 and C. jejuni contamination in tank milk (n = 785) and the in-line milk filters of milking machines (n = 631) versus the frequency of isolation from cattle feces (n = 257) on three Finnish dairy farms for 1 year. Despite simultaneous isolation of STEC O157:H7 (17%) or C. jejuni (53%) from cattle, these bacteria were rarely isolated from milk filters (2% or <1%, respectively) and milk (0%). As revealed by phylogenomics, one STEC O157:H7 strain at a time was detected on each farm and persisted for ≤12 months despite rigorous hygienic measures. C. jejuni strains of a generalist sequence type (ST-883 and ST-1080) persisted in the herds for ≥11 months, and several other C. jejuni types were detected sporadically. The stx gene carried by STEC was detected more frequently from milk filters (37%) than from milk (7%), suggesting that milk filters are more suitable sampling targets for monitoring than milk. A questionnaire of on-farm practices suggested lower stx contamination of milk when major cleansing in the barn, culling, or pasturing of dairy cows was applied, while a higher average outdoor temperature was associated with higher stx contamination. Because pathogen contamination occurred despite good hygiene and because pathogen detection from milk and milk filters proved challenging, we recommend heat treatment for raw milk before consumption.IMPORTANCE The increased popularity of raw milk consumption has created demand for relaxing legislation, despite the risk of contamination by pathogenic bacteria, notably STEC and C. jejuni However, the epidemiology of these milk-borne pathogens on the herd level is still poorly understood, and data are lacking on the frequency of milk contamination on farms with cattle shedding these bacteria in their feces. This study suggests (i) that STEC contamination in milk can be reduced, but not prevented, by on-farm hygienic measures while fecal shedding is observable, (ii) that milk filters are more suitable sampling targets for monitoring than milk although pathogen detection from both sample matrices may be challenging, and (iii) that STEC and C. jejuni genotypes may persist in cattle herds for several months. The results can be utilized in developing and targeting pathogen monitoring and risk management on the farm level and contributed to the revision of Finnish legislation in 2017.
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22
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Listeria monocytogenes in Milk: Occurrence and Recent Advances in Methods for Inactivation. BEVERAGES 2019. [DOI: 10.3390/beverages5010014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Milk is one of the most important food items consumed by humans worldwide. In addition to its nutritional importance, milk is an excellent culture medium for microorganisms, which may include pathogens such as Listeria monocytogenes (L. monocytogenes). Traditional processing of milk for direct consumption is based on thermal treatments that efficiently eliminate pathogens, including pasteurization or sterilization. However, the occurrence of L. monocytogenes in milk as a consequence of failures in the pasteurization process or postpasteurization contamination is still a matter of concern. In recent years, consumer demand for minimally processed milk has increased due to the perception of better sensory and nutritional qualities of the products. This review deals with the occurrence of L. monocytogenes in milk in the last 10 years, including regulatory aspects, and recent advances in technologies for the inactivation of this pathogen in milk. The results from studies on nonthermal technologies, such as high hydrostatic pressure, pulsed electric fields, ultrasounds, and ultraviolet irradiation, are discussed, considering their potential application in milk processing plants.
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Artursson K, Schelin J, Thisted Lambertz S, Hansson I, Olsson Engvall E. Foodborne pathogens in unpasteurized milk in Sweden. Int J Food Microbiol 2018; 284:120-127. [PMID: 29887505 DOI: 10.1016/j.ijfoodmicro.2018.05.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 05/11/2018] [Accepted: 05/17/2018] [Indexed: 11/15/2022]
Abstract
Raw milk may be a risk for public health if it is contaminated with zoonotic pathogens. To study the prevalence in unpasteurized milk from Swedish farms, bovine and small ruminant dairy farms were sampled. Since the sampling method and transport conditions may influence the outcome of analyses, efforts were made to optimize the methodology. Culturing of bacteria was done from in-line milk filters collected from the milk pipe at the point where it enters the milk bulk tank at the farms and this way of sampling was compared to sampling bulk tank milk (BTM) directly. Analysing milk filters were found to be superior to analysing BTM directly. Conditions for transport of milk filter samples were further improved by the addition of Cary Blair transport medium, which significantly increased the number of positive samples for pathogenic bacteria. The isolation of several foodborne pathogens from milk filters was demonstrated. The prevalence of samples with Staphylococcus aureus was 71% and 64%, and Listeria spp. 21% and 29% from dairy cow and goat/sheep farms, respectively. Campylobacter jejuni, Yersinia enterocolitica and verotoxigenic Escherichia coli (VTEC) O157 were detected in 9%, 2% and 2% of samples from bovine milk, respectively. We conclude that the choice of sampling method and sample handling influence the results of bacterial culturing. From the results of this study, we strongly recommend to sample in-line milk filters instead of BTM directly and to use Cary Blair medium during transport, especially if the samples are to be analysed for Campylobacter spp. and/or Listeria spp. The findings also show that unpasteurized milk from Swedish farms occasionally contain bacteria with zoonotic potential.
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Affiliation(s)
- Karin Artursson
- National Veterinary Institute, Uppsala, Sweden; Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Sweden.
| | - Jenny Schelin
- Applied Microbiology, Faculty of Engineering, Lund University, Lund, Sweden
| | - Susanne Thisted Lambertz
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Sweden; National Food Agency, Uppsala, Sweden
| | - Ingrid Hansson
- National Veterinary Institute, Uppsala, Sweden; Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Sweden
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24
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Castro H, Jaakkonen A, Hakkinen M, Korkeala H, Lindström M. Occurrence, Persistence, and Contamination Routes of Listeria monocytogenes Genotypes on Three Finnish Dairy Cattle Farms: a Longitudinal Study. Appl Environ Microbiol 2018; 84:e02000-17. [PMID: 29222098 PMCID: PMC5795088 DOI: 10.1128/aem.02000-17] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 11/30/2017] [Indexed: 11/20/2022] Open
Abstract
The molecular epidemiology of Listeria monocytogenes was investigated in a longitudinal study of three Finnish dairy farms during 2013 to 2016. A total of 186 bulk tank milk (BTM), 224 milk filter sock (MFS), and 1,702 barn environment samples were analyzed, and isolates of L. monocytogenes were genotyped using pulsed-field gel electrophoresis. L. monocytogenes occurred throughout the year in all sample types, and the prevalence in MFS increased significantly during the indoor season. L. monocytogenes was more prevalent in MFS (29%) than in BTM (13%) samples. However, the prevalence of L. monocytogenes varied more between farms in samples of MFS (13 to 48%) than in BTM (10 to 16%). For each farm, the L. monocytogenes genotypes detected were classified by persistence (defined as persistent if isolated from ≥3 samples during ≥6 months) and predominance (defined as predominant if >5% prevalence on at least one farm visit). The prevalence of sporadic genotypes was 4 to 5% on all three farms. In contrast, the prevalence of persistent predominant genotypes varied between farms by 4% to 16%. The highest prevalence of persistent predominant genotypes was observed on the farm with the poorest production hygiene. Persistent predominant genotypes were most prevalent on feeding surfaces, water troughs, and floors. Genotypes isolated from the milking system or from cow udders had a greater relative risk of occurring in BTM and MFS than genotypes that only occurred elsewhere in the farm, supporting the hypothesis that L. monocytogenes is transmitted to milk from contamination on the udder surface or in the milking equipment.IMPORTANCEListeria monocytogenes is a ubiquitous environmental bacterium and the causative agent of a serious foodborne illness, listeriosis. Dairy products are common vehicles of listeriosis, and dairy cattle farms harbor L. monocytogenes genotypes associated with human listeriosis outbreaks. Indeed, dairy cattle farms act as a reservoir of L. monocytogenes, and the organism is frequently detected in bulk tank milk (BTM) and in the feces of clinically healthy cows. The ecology of L. monocytogenes in the farm environment is complex and poorly understood. Isolates of the same L. monocytogenes genotype can occur in the farm for years, but the factors contributing to the persistence of genotypes on dairy farms are unknown. Knowledge of the persistence patterns and contamination routes of L. monocytogenes on dairy farms can improve management of the contamination pressure in the farm environment and aid in the development of focused control strategies to reduce BTM contamination.
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Affiliation(s)
- Hanna Castro
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Anniina Jaakkonen
- Microbiology Research Unit, Finnish Food Safety Authority (Evira), Helsinki, Finland
| | - Marjaana Hakkinen
- Microbiology Research Unit, Finnish Food Safety Authority (Evira), Helsinki, Finland
| | - Hannu Korkeala
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Miia Lindström
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
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25
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Wemmenhove E, van Valenberg H, van Hooijdonk A, Wells-Bennik M, Zwietering M. Factors that inhibit growth of Listeria monocytogenes in nature-ripened Gouda cheese: A major role for undissociated lactic acid. Food Control 2018. [DOI: 10.1016/j.foodcont.2017.08.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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26
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Bradley AJ, Leach KA, Green MJ, Gibbons J, Ohnstad IC, Black DH, Payne B, Prout VE, Breen JE. The impact of dairy cows' bedding material and its microbial content on the quality and safety of milk - A cross sectional study of UK farms. Int J Food Microbiol 2017; 269:36-45. [PMID: 29421356 DOI: 10.1016/j.ijfoodmicro.2017.12.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 11/13/2017] [Accepted: 12/18/2017] [Indexed: 10/18/2022]
Abstract
The introduction of bedding dairy cows on recycled manure solids (RMS) in the UK led to concern by competent authorities that there could be an increased, unacceptable risk to animal and human health. A cross-sectional study was designed to evaluate the microbial content of different bedding materials, when used by dairy cows, and its impact on the microbial content of milk. Data were collected from farms bedding lactating cows on sand (n=41), sawdust (n=44) and RMS (n=40). The mean duration of RMS use prior to sampling was 13months. Total bacterial count, and counts of Streptococcus/Enterococcus spp., Staphylococcus spp., Bacillus cereus, thermophilic, thermoduric and psychrotrophic bacteria were determined in used bedding and milk. Samples were evaluated for the presence/absence of Listeria monocytogenes, Salmonella spp. and Yersinia enterocolitica. Data on milking practices were collected to investigate their potential to reduce microbial transfer from bedding to milk. There were substantial differences in bacterial counts both within and between bedding materials. However, there were no significant differences between bedding groups in counts in milk for any of the organisms studied, and no significant correlations between bacterial load in used bedding and milk. Fore-milking was associated with a reduced total bacterial count in milk. Dipping teats with disinfectant and drying, prior to milking, was associated with lower numbers of Streptococcus/Enterococcus spp. in milk. Disinfecting clusters between milking different cows was associated with a reduction in thermophilic and psychrotrophic counts in milk. This study did not provide evidence that use of RMS bedding increased the risk of presence of Y. enterocolitica, Salmonella spp. or L. monocytogenes in milk. However, the strength of this conclusion should be tempered by the relatively small number of farms on which Y. enterocolitica and Salmonella spp. were isolated. It is concluded that, despite the higher bacterial load of RMS, its use as bedding for lactating dairy cows need not be associated with a higher bacterial load in milk than the use of sand or sawdust. However, this finding must be interpreted in the light of the relatively recent introduction of RMS as a bedding material on the farms studied. Teat preparation provides a control point for the potential transfer of microorganisms from bedding to milk. The detection of zoonotic pathogens in a small proportion of milk samples, independent of bedding type, indicates that pasteurisation of milk prior to human consumption remains an important control measure.
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Affiliation(s)
- Andrew J Bradley
- QMMS Ltd, Cedar Barn, Easton, Wells, Somerset BA5 1DU, UK; School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Leicestershire LE12 5RD, UK.
| | | | - Martin J Green
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Leicestershire LE12 5RD, UK.
| | - Jenny Gibbons
- AHDB Dairy, Stoneleigh Park, Kenilworth, Warwickshire CV8 2TL, UK.
| | - Ian C Ohnstad
- The Dairy Group, New Agriculture House, Blackbrook Park Avenue, Taunton, Somerset TA1 2PX, UK.
| | - David H Black
- Paragon Veterinary Group, Carlisle House, Townhead Road, Dalston, Carlisle, Cumbria CA5 7JF, UK.
| | - Barbara Payne
- QMMS Ltd, Cedar Barn, Easton, Wells, Somerset BA5 1DU, UK
| | | | - James E Breen
- QMMS Ltd, Cedar Barn, Easton, Wells, Somerset BA5 1DU, UK; School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Leicestershire LE12 5RD, UK
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27
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Kunová S, Golian J, Zeleňáková L, Lopašovský Ľ, Čuboň J, Haščík P, Kačániová M. Microbiological quality of fresh and heat treated cow's milk during storage. POTRAVINARSTVO 2017. [DOI: 10.5219/799] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aim of the present study was to evaluate the microbiological quality of raw milk from milk vending machine and heat treated milk during storage. There were analyzed 120 samples of milk (30 samples of fresh milk, 30 samples of raw milk stored 4 day at 4 °C, 30 samples of heat treated milk - 70 °C stored 4 day at 4 °C and 30 samples of heat treated milk - 100 °C stored 4 day at 4 °C). Total viable counts (TVC), coliform bacteria (CB) and microscopic filamentous fungi (MFF) were determined by microbiological analysis. Plate dilution method were used for microbiological analysis. The number of total viable counts (TVC) in fresh milk ranged from 4.08 log KTJ.mL-1 to 4.89 CFU.mL-1. TVC in raw milk after storage ranged from 5.31 log CFU.mL-1 to 6.81 log CFU.mL-1. TVC in heat treated milk with temperature 70 °C after storage ranged from 3.89 log CFU.mL-1 to 4.45 log CFU.mL-1 and TVC in heat treated milk with temperature 100 °C after storage ranged from 2.96 log KTJ.mL-1 to 3.91 log KTJ.mL-1 in heat treated milk with temperature 100 °C after storage. The number of CB were in range from 1.49 log CFU.mL-1 to 1.89 log CFU.mL-1 in fresh milk, from 1.99 log CFU.mL-1 to 2.61 log CFU.mL-1 in raw stored milk. Coliform bacteria were not present in heat-treated milk samples. The values of MFF ranged from 0 log CFU.mL-1 to 2.01 log CFU.mL-1 in fresh milk, from 1.43 log CFU.mL-1 to 3.98 log CFU.mL-1 in raw milk after storage, from 1.33 log CFU.mL-1 to 3.41 log CFU.mL-1 in heat treated milk with temperature 70 °C after storage and from 1.30 log CFU.mL-1 to 3.32 log CFU.mL-1 in heat treated milk with temperature 100 °C after storage.
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28
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Castro H, Ruusunen M, Lindström M. Occurrence and growth of Listeria monocytogenes in packaged raw milk. Int J Food Microbiol 2017; 261:1-10. [PMID: 28850852 DOI: 10.1016/j.ijfoodmicro.2017.08.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 06/30/2017] [Accepted: 08/20/2017] [Indexed: 10/19/2022]
Abstract
The increased availability of packaged raw drinking milk necessitates the investigation of the occurrence and growth of Listeria monocytogenes in raw milk during distribution and storage. The occurrence of L. monocytogenes in 105 retailed raw milk bottles, 115 bulk tank milk samples, 23 in-line milk filter socks and in 50 environmental samples collected from an on-farm dairy establishment were investigated. Growth of inoculated low-level L. monocytogenes contamination was also investigated in two types of raw milk packaging, namely in 1-litre plastic bottles and 3-litre bag-in-boxes, both stored at three different storage temperatures of 6, 8 and 10°C. The occurrence of L. monocytogenes was higher (4.8%) in bottled raw milk stored until the use-by-date of the package compared to fresh bulk tank milk (1.7%). L. monocytogenes counts were ≤13CFU/ml in bottled raw milk and ≤1CFU/ml in bulk tank milk. L. monocytogenes was not detected in the packaging facility, but occurred very frequently (39%) in the milk filter socks. Subtyping of L. monocytogenes isolates using pulsed-field gel-electrophoresis revealed seven pulsotypes, of which two occurred in multiple samples. Targeted inoculum levels of 1-2CFU/ml yielded L. monocytogenes counts≥100CFU/ml within seven days of storage in 22% of the raw milk packages stored at 6°C, and in all of the raw milk packages stored at 8°C. The frequent occurrence of L. monocytogenes in raw milk and the ability of a low-level L. monocytogenes contamination to grow at refrigeration temperatures highlight the importance of consumer education regarding the appropriate raw milk storage and handling.
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Affiliation(s)
- Hanna Castro
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Marjo Ruusunen
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Miia Lindström
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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29
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Lan X, Wang J, Zheng N, Zhao S, Li S, Li F. Prevalence and risk factors forBacillus cereusin raw milk in Inner Mongolia, Northern China. INT J DAIRY TECHNOL 2017. [DOI: 10.1111/1471-0307.12416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xinyi Lan
- Faculty of Animal Science and Technology; Gansu Agricultural University; Gansu 730070 Lanzhou China
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing); Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
- College of Animal Science and Technology; Hunan Agricultural University; Changsha Hunan Province China
- Ministry of Agriculture - Milk and Dairy Product Inspection Center (Beijing); Beijing 100193 China
| | - Jiaqi Wang
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing); Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
- Ministry of Agriculture - Milk and Dairy Product Inspection Center (Beijing); Beijing 100193 China
| | - Nan Zheng
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing); Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
- Ministry of Agriculture - Milk and Dairy Product Inspection Center (Beijing); Beijing 100193 China
| | - Shengguo Zhao
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing); Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
- Ministry of Agriculture - Milk and Dairy Product Inspection Center (Beijing); Beijing 100193 China
| | - Songli Li
- Ministry of Agriculture Laboratory of Quality and Safety Risk Assessment for Dairy Products (Beijing); Institute of Animal Science; Chinese Academy of Agricultural Sciences; Beijing 100193 China
- Ministry of Agriculture - Milk and Dairy Product Inspection Center (Beijing); Beijing 100193 China
| | - Fadi Li
- Faculty of Animal Science and Technology; Gansu Agricultural University; Gansu 730070 Lanzhou China
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30
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Lan XY, Zhao SG, Zheng N, Li SL, Zhang YD, Liu HM, McKillip J, Wang JQ. Short communication: Microbiological quality of raw cow milk and its association with herd management practices in Northern China. J Dairy Sci 2017; 100:4294-4299. [PMID: 28434737 DOI: 10.3168/jds.2016-11631] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 03/02/2017] [Indexed: 01/26/2023]
Abstract
Contamination of raw milk with bacterial pathogens is potentially hazardous to human health. The aim of this study was to evaluate the total bacteria count (TBC) and presence of pathogens in raw milk in Northern China along with the associated herd management practices. A total of 160 raw milk samples were collected from 80 dairy herds in Northern China. All raw milk samples were analyzed for TBC and pathogens by culturing. The results showed that the number of raw milk samples with TBC <2 × 106 cfu/mL and <1 × 105 cfu/mL was 146 (91.25%) and 70 (43.75%), respectively. A total of 84 (52.50%) raw milk samples were Staphylococcus aureus positive, 72 (45.00%) were Escherichia coli positive, 2 (1.25%) were Salmonella positive, 2 (1.25%) were Listeria monocytogenes positive, and 3 (1.88%) were Campylobacter positive. The prevalence of S. aureus was influenced by season, herd size, milking frequency, disinfection frequency, and use of a Dairy Herd Improvement program. The TBC was influenced by season and milk frequency. The correlation between TBC and prevalence of S. aureus or E. coli is significant. The effect size statistical analysis showed that season and herd (but not Dairy Herd Improvement, herd size, milking frequency, disinfection frequency, and area) were the most important factors affecting TBC in raw milk. In conclusion, the presence of bacteria in raw milk was associated with season and herd management practices, and further comprehensive study will be powerful for effectively characterizing various factors affecting milk microbial quality in bulk tanks in China.
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Affiliation(s)
- X Y Lan
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture (Beijing), Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China; College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, Hunan Province, P. R. China; College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, Gansu Province, P. R. China
| | - S G Zhao
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture (Beijing), Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - N Zheng
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture (Beijing), Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - S L Li
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture (Beijing), Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - Y D Zhang
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture (Beijing), Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - H M Liu
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture (Beijing), Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China
| | - J McKillip
- Department of Biology, Ball State University, Muncie, IN 47306
| | - J Q Wang
- Laboratory of Quality and Safety Risk Assessment for Dairy Products of Ministry of Agriculture (Beijing), Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, P. R. China.
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31
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Jaakkonen A, Salmenlinna S, Rimhanen-Finne R, Lundström H, Heinikainen S, Hakkinen M, Hallanvuo S. Severe Outbreak of Sorbitol-Fermenting Escherichia coli O157 via Unpasteurized Milk and Farm Visits, Finland 2012. Zoonoses Public Health 2017; 64:468-475. [PMID: 28045227 DOI: 10.1111/zph.12327] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Indexed: 12/31/2022]
Abstract
Shiga toxin-producing, sorbitol-fermenting Escherichia coli O157 (SF O157) has emerged as a cause of severe human illness. Despite frequent human findings, its transmission routes and reservoirs remain largely unknown. Foodborne transmission and reservoir in cattle have been suspected, but with limited supporting evidence. This study describes the outbreak of SF O157 that occurred in Finland in 2012. The outbreak originated from a recreational farm selling unpasteurized milk, as revealed by epidemiologic and microbiological investigations, and involved six hospitalized children and two asymptomatic adults with culture-confirmed infection. An identical strain of SF O157 was isolated from patients, cattle and the farm environment, and epidemiologic analysis suggested unpasteurized milk as the vehicle of transmission. This study reports the first milkborne outbreak of SF O157, provides supporting evidence of cattle as a reservoir and highlights the health risks related to the consumption of unpasteurized milk.
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Affiliation(s)
- A Jaakkonen
- Finnish Food Safety Authority Evira, Helsinki, Finland
| | - S Salmenlinna
- National Institute for Health and Welfare (THL), Helsinki, Finland
| | - R Rimhanen-Finne
- National Institute for Health and Welfare (THL), Helsinki, Finland
| | | | - S Heinikainen
- Finnish Food Safety Authority Evira, Kuopio, Finland
| | - M Hakkinen
- Finnish Food Safety Authority Evira, Helsinki, Finland
| | - S Hallanvuo
- Finnish Food Safety Authority Evira, Helsinki, Finland
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32
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Christidis T, Pintar KDM, Butler AJ, Nesbitt A, Thomas MK, Marshall B, Pollari F. Campylobacter spp. Prevalence and Levels in Raw Milk: A Systematic Review and Meta-Analysis. J Food Prot 2016; 79:1775-1783. [PMID: 28221843 DOI: 10.4315/0362-028x.jfp-15-480] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Campylobacteriosis is the leading bacterial gastrointestinal disease internationally, contributing significantly to the enteric illness burden. Cases have been associated with the consumption of raw milk, a behavior that has garnered attention recently. Estimates of the prevalence and levels of Campylobacter spp. in raw milk are lacking, which hinders risk assessment attempts. This article is a systematic review and meta-analysis of reported prevalence and levels of zoonotic Campylobacter spp. in the raw milk of cows, goats, and sheep in Canada, the United States, Europe, Australia, and New Zealand. The relevant literature was reviewed, and trained reviewers examined the results for inclusion of articles in the meta-analysis. Relevant data (prevalence and/or level of Campylobacter in raw milk, country of origin, animal species, sample source, Campylobacter species identified, etc.) were extracted, and a meta-analysis was performed in Stata v. 12 (Metaprop command). The weighted mean prevalence of Campylobacter spp. in raw milk samples was 1.18%. Subgroup analyses were conducted to examine how prevalence varied by study characteristics, with the highest prevalence values in studies from the United Kingdom (by country, 6.4%), about cows (by animal species, 1.3%), and including samples taken from inline filters (by sample source, 1.75%) and in studies that included species that are not pathogenic to humans (by Campylobacter species, 1.14%). Two articles each included a single Campylobacter level, 0.16 ± 0.3 and approximately 0.047 most probable number per ml. Despite a relatively low prevalence, consumption of raw milk is inherently risky because no treatment has been used to inactivate pathogens. This potential risk further supports maintaining regulations to limit the sales of raw milk.
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Affiliation(s)
- T Christidis
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada K1A 0K9
| | - K D M Pintar
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada K1A 0K9
| | - A J Butler
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada K1A 0K9
| | - A Nesbitt
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada K1A 0K9
| | - M K Thomas
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada K1A 0K9
| | - B Marshall
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada K1A 0K9
| | - F Pollari
- Centre for Food-borne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Ottawa, Ontario, Canada K1A 0K9
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33
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Odenthal S, Akineden Ö, Usleber E. Extended-spectrum β-lactamase producing Enterobacteriaceae in bulk tank milk from German dairy farms. Int J Food Microbiol 2016; 238:72-78. [PMID: 27592073 DOI: 10.1016/j.ijfoodmicro.2016.08.036] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 08/22/2016] [Accepted: 08/28/2016] [Indexed: 11/26/2022]
Abstract
Although the dairy farm environment is a known source of extended-spectrum β-lactamase (ESBL)-producing bacteria, surveillance data on ESBL in the milk production chain are still scarce. This study aimed at estimating the dimensions of the problem for public health and animal welfare by surveying ESBL-producing Enterobacteriaceae in raw bulk tank milk in Germany. Samples from 866 dairy farms, comprising about 1% of the total number of dairy farms in Germany, were first screened for presence of cefotaxime-resistant bacteria by selective enrichment. Suspect colonies were identified phenotypically and further characterized by biochemical and molecular methods, including analysis of resistance genes and clonal diversity in ESBL-producing isolates. Bulk tank milk from 82 (9.5%) farms yielded Enterobacteriaceae with confirmed ESBL-production. The most frequent ESBL-producing species was Escherichia coli (75.6%), followed by Citrobacter spp. (9.6%), Enterobacter cloacae (6.1%), and Klebsiella oxytoca (3.7%), a few isolates belonged to other species within the genera Hafnia, Raoutella and Serratia. The majority of isolates (95.1%) harbored the β-lactamase blaCTX-M gene, which has gained increased importance among ESBL-producing strains worldwide; the CTX-M group 1 was found to be the dominating (88.4%) phylogenetic group. All ESBL-positive Escherichia coli isolates were clonally heterogeneous, as determined by pulsed-field gel electrophoresis. The results from this survey demonstrate that ESBL-producing bacteria are distributed widely in the dairy farm environment in Germany. Therefore, raw milk is a potential source of exposure for the consumer, which is of increasing importance considering the trend of farmer-to-consumer direct marketing. Furthermore, dairy farm staff have an increased likelihood of exposure to ESBL-producing bacteria. Finally, ESBL-producing bacteria may also be transferred via waste milk to calves, thus further spreading antibiotic resistance in the farm environment.
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Affiliation(s)
- Sabrina Odenthal
- Dairy Sciences, Institute of Veterinary Food Science, Justus-Liebig University Giessen, Ludwigstrasse 21, D-35390 Giessen, Germany
| | - Ömer Akineden
- Dairy Sciences, Institute of Veterinary Food Science, Justus-Liebig University Giessen, Ludwigstrasse 21, D-35390 Giessen, Germany.
| | - Ewald Usleber
- Dairy Sciences, Institute of Veterinary Food Science, Justus-Liebig University Giessen, Ludwigstrasse 21, D-35390 Giessen, Germany
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34
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Zhu K, Hölzel CS, Cui Y, Mayer R, Wang Y, Dietrich R, Didier A, Bassitta R, Märtlbauer E, Ding S. Probiotic Bacillus cereus Strains, a Potential Risk for Public Health in China. Front Microbiol 2016; 7:718. [PMID: 27242738 PMCID: PMC4876114 DOI: 10.3389/fmicb.2016.00718] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 04/29/2016] [Indexed: 12/14/2022] Open
Abstract
Bacillus cereus is an important cause of foodborne infectious disease and food poisoning. However, B. cereus has also been used as a probiotic in human medicine and livestock production, with low standards of safety assessment. In this study, we evaluated the safety of 15 commercial probiotic B. cereus preparations from China in terms of mislabeling, toxin production, and transferable antimicrobial resistance. Most preparations were incorrectly labeled, as they contained additional bacterial species; one product did not contain viable B. cereus at all. In total, 18 B. cereus group strains-specifically B. cereus and Bacillus thuringiensis-were isolated. Enterotoxin genes nhe, hbl, and cytK1, as well as the ces-gene were assessed by PCR. Enterotoxin production and cytotoxicity were confirmed by ELISA and cell culture assays, respectively. All isolated B. cereus group strains produced the enterotoxin Nhe; 15 strains additionally produced Hbl. Antimicrobial resistance was assessed by microdilution; resistance genes were detected by PCR and further characterized by sequencing, transformation and conjugation assays. Nearly half of the strains harbored the antimicrobial resistance gene tet(45). In one strain, tet(45) was situated on a mobile genetic element-encoding a site-specific recombination mechanism-and was transferable to Staphylococcus aureus and Bacillus subtilis by electro-transformation. In view of the wide and uncontrolled use of these products, stricter regulations for safety assessment, including determination of virulence factors and transferable antimicrobial resistance genes, are urgently needed.
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Affiliation(s)
- Kui Zhu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural UniversityBeijing, China; Department of Veterinary Sciences, Ludwig Maximilian University of MunichOberschleißheim, Germany
| | - Christina S Hölzel
- Department of Veterinary Sciences, Ludwig Maximilian University of Munich Oberschleißheim, Germany
| | - Yifang Cui
- National Center for Veterinary Drug Safety Evaluation, China Agricultural University Beijing, China
| | - Ricarda Mayer
- Department of Veterinary Sciences, Ludwig Maximilian University of Munich Oberschleißheim, Germany
| | - Yang Wang
- National Center for Veterinary Drug Safety Evaluation, China Agricultural University Beijing, China
| | - Richard Dietrich
- Department of Veterinary Sciences, Ludwig Maximilian University of Munich Oberschleißheim, Germany
| | - Andrea Didier
- Department of Veterinary Sciences, Ludwig Maximilian University of Munich Oberschleißheim, Germany
| | - Rupert Bassitta
- Department of Veterinary Sciences, Ludwig Maximilian University of Munich Oberschleißheim, Germany
| | - Erwin Märtlbauer
- Department of Veterinary Sciences, Ludwig Maximilian University of Munich Oberschleißheim, Germany
| | - Shuangyang Ding
- National Center for Veterinary Drug Safety Evaluation, China Agricultural University Beijing, China
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35
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Marshall JC, Soboleva TK, Jamieson P, French NP. Estimating Bacterial Pathogen Levels in New Zealand Bulk Tank Milk. J Food Prot 2016; 79:771-80. [PMID: 27296424 DOI: 10.4315/0362-028x.jfp-15-230] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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.
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Affiliation(s)
- J C Marshall
- Institute of Fundamental Sciences, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North 4474, New Zealand.
| | - T K Soboleva
- Ministry for Primary Industries, Pastoral House, The Terrace, Wellington 6011, New Zealand
| | - P Jamieson
- MilkTestNZ, 1344 Te Rapa Road, Hamilton 3288, New Zealand
| | - N P French
- mEpiLab, Infectious Disease Research Centre, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North 4474, New Zealand
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36
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Pärn T, Hallanvuo S, Salmenlinna S, Pihlajasaari A, Heikkinen S, Telkki-Nykänen H, Hakkinen M, Ollgren J, Huusko S, Rimhanen-Finne R. Outbreak of Yersinia pseudotuberculosis O:1 infection associated with raw milk consumption, Finland, spring 2014. ACTA ACUST UNITED AC 2016; 20:30033. [PMID: 26537540 DOI: 10.2807/1560-7917.es.2015.20.40.30033] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 06/04/2015] [Indexed: 11/20/2022]
Abstract
In March 2014, a Yersinia pseudotuberculosis (YP) outbreak was detected by a municipal authority in southern Finland. We conducted epidemiological, microbiological and traceback investigations to identify the source. We defined a case as a person with YP infection notified to the National Infectious Disease Registry between February and April 2014, or their household member, with abdominal pain and fever≥38 °C or erythema nodosum. Healthy household members were used as household-matched controls. We identified 43 cases and 50 controls. The illness was strongly associated with the consumption of raw milk from a single producer. The odds ratio of illness increased with the amount of raw milk consumed. Also previously healthy adults became infected by consuming raw milk. Identical YP strains were identified from cases' stool samples, raw milk sampled from a case's refrigerator and from the milk filter at the producer's farm. The producer fulfilled the legal requirements for raw milk production and voluntarily recalled the raw milk and stopped its production. We advised consumers to heat the raw milk to 72 °C for 15 s. Current legislation for raw milk producers should be reviewed and public awareness of health risks linked to raw milk consumption should be increased.
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Affiliation(s)
- Triin Pärn
- National Institute for Health and Welfare (THL), Department of Infectious Diseases Surveillance and Control, Helsinki, Finland
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37
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Survey of prevalence and seasonal variability of Listeria monocytogenes in raw cow milk from Northern Italy. Food Control 2016. [DOI: 10.1016/j.foodcont.2015.08.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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38
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Hou Q, Xu H, Zheng Y, Xi X, Kwok LY, Sun Z, Zhang H, Zhang W. Evaluation of bacterial contamination in raw milk, ultra-high temperature milk and infant formula using single molecule, real-time sequencing technology. J Dairy Sci 2015; 98:8464-72. [PMID: 26476945 DOI: 10.3168/jds.2015-9886] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 07/28/2015] [Indexed: 01/07/2023]
Abstract
The Pacific Biosciences (Menlo Park, CA) single molecule, real-time sequencing technology (SMRT) was reported to have some advantages in analyzing the bacterial profile of environmental samples. In this study, the presence of bacterial contaminants in raw milk, UHT milk, and infant formula was determined by SMRT sequencing of the full length 16S rRNA gene. The bacterial profiles obtained at different taxonomic levels revealed clear differences in bacterial community structure across the 16 analyzed dairy samples. No indicative pathogenic bacteria were found in any of these tested samples. However, some of the detected bacterial species (e.g., Bacillus cereus, Enterococcus casseliflavus, and Enterococcus gallinarum) might potentially relate with product quality defects and bacterial antibiotic gene transfer. Although only a limited number of dairy samples were analyzed here, our data have demonstrated for the first time the feasibility of using the SMRT sequencing platform in detecting bacterial contamination. Our paper also provides interesting reference information for future development of new precautionary strategies for controlling the dairy safety in large-scale industrialized production lines.
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Affiliation(s)
- Qiangchuan Hou
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Haiyan Xu
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Yi Zheng
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Xiaoxia Xi
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Lai-Yu Kwok
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Zhihong Sun
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Heping Zhang
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China
| | - Wenyi Zhang
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, China, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China.
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39
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Özdemir F, Arslan S. Genotypic and phenotypic virulence characteristics and antimicrobial resistance ofYersiniaspp. isolated from meat and milk products. J Food Sci 2015; 80:M1306-13. [DOI: 10.1111/1750-3841.12911] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 04/20/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Fatma Özdemir
- Abant Izzet Baysal Univ, Faculty of Arts and Sciences; Dept. of Biology; 14280 Gölköy/Bolu Turkey
| | - Seza Arslan
- Abant Izzet Baysal Univ, Faculty of Arts and Sciences; Dept. of Biology; 14280 Gölköy/Bolu Turkey
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40
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Kalmus P, Kramarenko T, Roasto M, Meremäe K, Viltrop A. Quality of raw milk intended for direct consumption in Estonia. Food Control 2015. [DOI: 10.1016/j.foodcont.2014.11.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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41
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Scientific Opinion on the public health risks related to the consumption of raw drinking milk. EFSA J 2015. [DOI: 10.2903/j.efsa.2015.3940] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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42
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Revez J, Huuskonen M, Ruusunen M, Lindström M, Hänninen ML. Arcobacter species and their pulsed-field gel electrophoresis genotypes in Finnish raw milk during summer 2011. J Food Prot 2013; 76:1630-2. [PMID: 23992510 DOI: 10.4315/0362-028x.jfp-13-083] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The aim of this study was to investigate the occurrence of Arcobacter species in raw milk in Finland. A total of 177 raw milk samples, each from a separate farm, were examined from June to August 2011. Arcobacter species were isolated using an enrichment and selective detection procedure. Overall, 26 (15 % ) of the 177 samples yielded Arcobacter spp. Samples from 25 farms were positive for Arcobacter butzleri and from 1 farm for Arcobacter cryaerophilus. Moreover, both Arcobacter butzleri and A. cryaerophilus were recovered from 1 positive sample. To evaluate a possible genetic variability, one strain of A. butzleri from each farm and the A. cryaerophilus sample were analyzed by pulsed-field gel electrophoresis. Genotyping revealed that Arcobacter spp. populations are heterogeneous, and no dominant clone has spread in the investigated samples. Our study is the first report on the isolation of both A. butzleri and A. cryaerophilus in raw milk in Finland. Based on our findings, the presence of Arcobacter species in raw milk may pose a potential hazard for human health, in particular for consumers who prefer drinking unpasteurized milk.
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Affiliation(s)
- Joana Revez
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, P.O. Box 66, FI-00014, Helsinki, Finland.
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