EVALUATION OF THE MICROBIAL LOAD AND IDENTIFICATION OF POSSIBLE SOURCES OF CONTAMINATION OF RAW COW’S MILK IN JOANNA, BLACK BUSH POLDER, REGION 6, GUYANA

Milk is one of the main sources of nutrients to animals, but due to its high water activity, it serves as an ideal medium for the growth of microorganisms. The purpose of this research was to evaluate the microbial load in raw cow’s milk and to identify the possible sources of raw milk contamination in Joanna. Fifteen (15) raw milk samples were collected randomly according to the simple random sampling method and farmers were interviewed. Raw milk samples were analysed for Escherichia coli and aerobic bacteria. From the 15 samples of raw milk, contamination with E. coli (93.33%) and aerobic bacteria (100%) was observed. Also, several factors, milk handling practices, unhygienic practices, extensive farming systems, and lack of general zoonoses exposure practices and awareness, predisposed raw milk to microbial contamination. This research concluded that the quality of milk was unsatisfactory since it was heavily contaminated with bacteria. It is recommended that there should be an increase in the agriculture extension education and awareness programme to help improve milk quality.

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Longitudinal Analysis of the Microbiological Quality of Raw Cow's Milk Samples Collected from Three Small Family Dairy Farms in Mexico Over a 2-Year Period

Journal of Food Protection ◽

10.4315/0362-028x.jfp-19-155 ◽

2019 ◽

Vol 82 (12) ◽

pp. 2194-2200 ◽

Cited By ~ 1

Author(s):

DIANA RIOS-MUÑIZ ◽

JORGE F. CERNA-CORTES ◽

CATALINA LOPEZ-SAUCEDO ◽

ERIKA ANGELES-MORALES ◽

MIRIAM BOBADILLA-del VALLE ◽

...

Keyword(s):

Salmonella Enterica ◽

Microbiological Quality ◽

Dairy Farms ◽

Raw Milk ◽

Cow’S Milk ◽

Cow's Milk ◽

E Coli ◽

Milk Samples ◽

Three Samples ◽

Raw Cow’S Milk

ABSTRACT In Mexico, the total milk production that family dairy farms (FDF) contribute is ca. 35%, but this milk is not evaluated for microbiological quality. Forty percent of the milk and dairy products consumed by Mexicans is unpasteurized. In total, 24 raw cow's milk samples from three FDF (one sample per each season from each FDF for two sequent years) were characterized for the presence of food quality indicator organisms, Staphylococcus aureus, Salmonella enterica, Listeria monocytogenes, and Mycobacterium spp., by standard procedures. Escherichia coli presence was also evaluated by a direct count method and diarrheagenic E. coli (DEC) by molecular methods. On the basis of Mexican guidelines for raw milk entering production, 42% of samples exceeded the aerobic mesophilic bacteria limits. A total of 83% raw milk samples were positive for total coliforms, 54% for fecal coliforms, and 46% for E. coli. Forty-three E. coli isolates were selected and characterized for the presence of 11 DEC loci; of theses, 40 isolates were negative for all DEC loci, and 3 isolates, all collected from the same sample, were Shiga toxin 2 (stx2) positive and O157 antigen negative, and one stx2 isolate was resistant to 6 of the 16 antibiotics tested. None of the 24 raw milk samples were positive for Salmonella enterica, L. monocytogenes, or staphylococcal enterotoxin. S. aureus was isolated from nine samples, of which only three samples harbored resistant isolates. From three samples, four nontuberculous mycobacterial isolates were recovered (Mycobacteroides chelonae, Mycobacteroides porcinum, and two Mycobacteroides abscessus). All four isolates produced biofilm and had sliding motility, and three isolates (M. porcinum and two M. abscessus) were resistant to the two antibiotics tested (clarithromycin and linezolid). FDF provide raw milk to a large proportion of the Mexican population, but its consumption could be harmful to health, emphasizing the need to implement national microbiological quality guidelines for raw milk intended for direct human consumption. HIGHLIGHTS

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Isolation and Molecular Identification and Antimicrobial Susceptibility of Providencia spp. from Raw Cow’s Milk in Baghdad, Iraq

Veterinary Medicine International ◽

10.1155/2020/8874747 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Nagham Mohammed Ayyal Al‐Gburi

Keyword(s):

Antimicrobial Susceptibility ◽

Raw Milk ◽

Diffusion Method ◽

Cow’S Milk ◽

Biochemical Tests ◽

Street Vendors ◽

Cow's Milk ◽

Milk Samples ◽

Biolog Gn ◽

Raw Cow’S Milk

A total of sixty raw milk samples were collected from (street vendors and shops) from Baghdad city, Iraq. The samples were inoculated into peptone water and, then, subcultured onto McConkey agar and Blood agar. Identification of isolates was confirmed by microscopic examination, cultural characteristic, biochemical tests, Vitek (VITEK®2 system), and Biolog GN substrate reactions followed by 16S rRNA and specific genes sequencing. Of 60 raw cow’s milk samples, Providencia spp. were identified only in 4 samples (6.67%) and P. rettgeri was the most common, 2/4 (50%), followed by P. stuartii and P. vermicola, 1/4 (25%) . Antimicrobial susceptibility tests were conducted against ten antibiotics by the disc diffusion method. All Providencia isolates showed multidrug resistance (MDR), and the absolute resistant was 100% to tetracycline, erythromycin, and doxycycline and 50% against ampicillin\sulbactam and amoxicillin/clavulanic acid. They were highly susceptible (100%) to trimethoprim, imipenem, and chloramphenicol. These findings indicate that milk might be contaminated with Providencia spp. leading to transmission to humans causing poisoning, diarrhea, and other infections. This is the first study of isolated Providencia spp. from raw cow’s milk.

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The effect of season on the microbiological status of raw milk

Acta Agraria Debreceniensis ◽

10.34101/actaagrar/1/3774 ◽

2020 ◽

pp. 95-99

Author(s):

Flóra Mária Szabóné Petróczki ◽

Béla Béri ◽

Ferenc Peles

Keyword(s):

Microbiological Quality ◽

Raw Milk ◽

Coliform Bacteria ◽

Plate Count ◽

Cow’S Milk ◽

Cow's Milk ◽

Milk Samples ◽

Significant Difference ◽

The Mean ◽

Raw Cow’S Milk

Many factors can influence the microbiological quality of raw cow’s milk. In this study, our aim was to determine whether there was any difference between the microbiological statuses of milk produced in different seasons. Samples were collected and analysed from five dairy farms in Hajdú-Bihar County, from February to November in 2019. During our studies, total plate count (TPC), coliform count and Staphylococcus aureus count of raw cow’s milk samples were determined. There was no significant difference (P>0.05) between the mean TPC values detected in the milk collected in winter and autumn, but that values were significantly (P<0.05) lower than in the milk samples collected in spring and summer. Similarly to the TPC, in the case of coliform bacteria the lowest mean colony count was detected in the samples collected in winter. The difference was significant (P<0.05), compared to the values observed in the samples collected in summer. S. aureus was detected in bulk milk of only two farms in excess of 1.0 log10 cfu/ml. Also in case of S. aureus, there was a significant difference (P<0.05) between the values observed in the samples collected in winter and in summer. Samples from spring and summer contained the highest amount of S. aureus. Based on the results of our studies, in the case of almost all farms the mean TPC, coliform and S. aureus counts were lower in the samples collected in winter, than in the samples collected in summer. The fact that the samples collected in winter contained the lowest amount of colonies could be attributed to the inhibition of growth of mesophilic microorganisms below 8 °C. Furthermore, the fact that we observed the highest colony counts in samples collected in summer, can be related to the heat stress of cows during the summer due to unfavorable weather conditions (high temperature and humidity).

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Direct Inhibition of the Allergic Effector Response by Raw Cow’s Milk—An Extensive In Vitro Assessment

Cells ◽

10.3390/cells9051258 ◽

2020 ◽

Vol 9 (5) ◽

pp. 1258

Author(s):

Suzanne Abbring ◽

Bart R. J. Blokhuis ◽

Julie L. Miltenburg ◽

Kiri G. J. Romano Olmedo ◽

Johan Garssen ◽

...

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Cell Activation ◽

Allergic Diseases ◽

Raw Milk ◽

Mast Cell Activation ◽

Cow’S Milk ◽

Cow's Milk ◽

Ige Mediated ◽

Raw Cow’S Milk

The mechanisms underlying the allergy-protective effects of raw cow’s milk are poorly understood. The current focus is mainly on the modulation of T cell responses. In the present study, we investigated whether raw cow’s milk can also directly inhibit mast cells, the key effector cells in IgE-mediated allergic responses. Primary murine bone marrow-derived mast cells (BMMC) and peritoneal mast cells (PMC), were incubated with raw milk, heated raw milk, or shop milk, prior to IgE-mediated activation. The effects on mast cell activation and underlying signaling events were assessed. Raw milk was furthermore fractionated based on molecular size and obtained fractions were tested for their capacity to reduce IgE-mediated mast cell activation. Coincubation of BMMC and PMC with raw milk prior to activation reduced β-hexosaminidase release and IL-6 and IL-13 production, while heated raw milk or shop milk had no effect. The reduced mast cell activation coincided with a reduced intracellular calcium influx. In addition, SYK and ERK phosphorylation levels, both downstream signaling events of the FcεRI, were lower in raw milk-treated BMMC compared to control BMMC, although differences did not reach full significance. Raw milk-treated BMMC furthermore retained membrane-bound IgE expression after allergen stimulation. Raw milk fractionation showed that the heat-sensitive raw milk components responsible for the reduced mast cell activation are likely to have a molecular weight of > 37 kDa. The present study demonstrates that raw cow’s milk can also directly affect mast cell activation. These results extend the current knowledge on mechanisms via which raw cow’s milk prevents allergic diseases, which is crucial for the development of new, microbiologically safe, nutritional strategies to reduce allergic diseases.

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Suppression of Food Allergic Symptoms by Raw Cow’s Milk in Mice is Retained after Skimming but Abolished after Heating the Milk—A Promising Contribution of Alkaline Phosphatase

Nutrients ◽

10.3390/nu11071499 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1499 ◽

Cited By ~ 7

Author(s):

Suzanne Abbring ◽

Joseph Thomas Ryan ◽

Mara A.P. Diks ◽

Gert Hols ◽

Johan Garssen ◽

...

Keyword(s):

Alkaline Phosphatase ◽

Protective Effect ◽

Raw Milk ◽

Fat Content ◽

Cow’S Milk ◽

Protective Effects ◽

Pasteurized Milk ◽

Cow's Milk ◽

Allergic Symptoms ◽

Raw Cow’S Milk

Raw cow’s milk was previously shown to suppress allergic symptoms in a murine model for food allergy. In the present study, we investigated the contribution of fat content and heat-sensitive milk components to this allergy-protective effect. In addition, we determined the potency of alkaline phosphatase (ALP), a heat-sensitive raw milk component, to affect the allergic response. C3H/HeOuJ mice were treated with raw milk, pasteurized milk, skimmed raw milk, pasteurized milk spiked with ALP, or phosphate-buffered saline for eight days prior to sensitization and challenge with ovalbumin (OVA). Effects of these milk types on the allergic response were subsequently assessed. Similar to raw milk, skimmed raw milk suppressed food allergic symptoms, demonstrated by a reduced acute allergic skin response and low levels of OVA-specific IgE and Th2-related cytokines. This protective effect was accompanied by an induction of CD103+CD11b+ dendritic cells and TGF-β-producing regulatory T cells in the mesenteric lymph nodes. Pasteurized milk was not protective but adding ALP restored the allergy-protective effect. Not the fat content, but the heat-sensitive components are responsible for the allergy-protective effects of raw cow’s milk. Adding ALP to heat-treated milk might be an interesting alternative to raw cow’s milk consumption, as spiking pasteurized milk with ALP restored the protective effects.

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Enumeration and Confirmation of Aeromonas hydrophila, Aeromonas caviae, and Aeromonas sobria Isolated from Raw Milk and Other Milk Products in Northern Greece

Journal of Food Protection ◽

10.4315/0362-028x-62.5.463 ◽

1999 ◽

Vol 62 (5) ◽

pp. 463-466 ◽

Cited By ~ 20

Author(s):

DIMITRIOS S. MELAS ◽

DEMETRIOS K. PAPAGEORGIOU ◽

ANTONIOS I. MANTIS

Keyword(s):

Raw Milk ◽

Cow’S Milk ◽

Aeromonas Species ◽

Northern Greece ◽

Cow's Milk ◽

Milk Samples ◽

Aeromonas Sobria ◽

Aeromonas Caviae ◽

Feta Cheese ◽

Ewe's Milk

A total of 138 raw cow's and 57 raw ewe's milk samples; 80 pasteurized cow's milk samples; 39 Anthotyros cheese, 36 Manouri cheese, and 23 Feta cheese samples; and 15 rice pudding samples were examined for the presence and any countable population of Aeromonas species. Twenty-two (15.9%) of the 138 cow's milk samples analyzed were contaminated with A. hydrophila. In 13 of these samples, populations of 3.0 × 102 to 5.0 × 103 CFU/ml were counted in starch ampicillin agar (SAA). Eighteen cow's milk samples (13.0%) were contaminated with A. caviae, and in eight of these samples, populations of 2.0 × 102 to 3.0 × 103 CFU/ml were counted in SAA. Five cow's milk samples (3.6%) were contaminated with A. sobria, and in two of these samples, populations of 2.5 × 103 and 5.0 × 103 CFU/ml were counted in SAA. Eleven cow's milk samples (7.9%) were contaminated with other Aeromonas spp. not classified. Eight (14.0%) of the 57 ewe's milk samples analyzed were contaminated with A. hydrophila. In these samples, populations of 5.0 × 102 to 5.0 × 103 CFU/ml were counted in SAA. Six ewe's milk samples (10.5%) were contaminated with A. caviae, and populations of 1.5 × 102 to 1.0 × 103 CFU/ml were counted in SAA. Two ewe's milk samples (3.5%) were contaminated with A. sobria, and populations counted in SAA were 5.0 × 102 and 1.0 × 103 CFU/ml. Four samples (7.0%) were contaminated with other Aeromonas spp. not classified. A. hydrophila was recovered in 4 (10.2%) and 3 (8.3%) of the Anthotyros and Manouri cheese samples analyzed, respectively, but no countable populations were noted in SAA. None of the pasteurized milk, Feta cheese, and rice pudding samples yielded Aeromonas spp. The results of this work indicate that motile Aeromonas are common in raw milk in Greece. Also, the presence of A. hydrophila in the whey cheeses Anthotyros and Manouri indicates that postprocessing contaminations of these products with motile Aeromonas may occur during production.

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A survey on the occurrence of aflatoxin M1 in raw milk samples in Bafq and Bahabad, Iran

Journal of Food Safety and Hygiene ◽

10.18502/jfsh.v5i3.5694 ◽

2021 ◽

Author(s):

Vahid Safavizadeh ◽

Mozhgan Mojkar

Keyword(s):

Aspergillus Parasiticus ◽

Raw Milk ◽

National Standard ◽

Aflatoxin M1 ◽

Cow’S Milk ◽

Elisa Method ◽

Cow's Milk ◽

Milk Samples ◽

The City

Aflatoxins are a group of mycotoxins mostly produced by the fungi called Aspergillus flavus, Aspergillus parasiticus, and Aspergillus nomium. Aflatoxin M1 (AFM1) is the major metabolite of aflatoxin B1 and is a hepatotoxic and carcinogenic toxin. The aim of this study was to determine the level of contamination of cow's milk with aflatoxin M1 in Bafq and Bahabad. For this study, samples of raw cow's milk were collected randomly from milk collection centers around the city of Bafq and Bahabad from March to April. The determination of aflatoxin M1 levels was based on the ELISA method. Contamination was observed in 100% of milk samples. According to the results of the study, the rate of contamination with aflatoxin M1 in 43.3% of milk samples was above the acceptable level (50 ng/L) in Iranian national standard. It is concluded that further monitoring of milk production should be carried out in the spring and winter seasons.

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Towards Simazine Monitoring in Agro-Zootechnical Productions: A Yeast Cell Bioprobe for Real Samples Screening

Biosensors ◽

10.3390/bios8040112 ◽

2018 ◽

Vol 8 (4) ◽

pp. 112 ◽

Cited By ~ 2

Author(s):

Gerardo Grasso ◽

Ludovico Caracciolo ◽

Giulia Cocco ◽

Chiara Frazzoli ◽

Roberto Dragone

Keyword(s):

Drinking Water ◽

Cellular Proliferation ◽

Dose Effect ◽

Yeast Cells ◽

Cow’S Milk ◽

Aerobic Respiration ◽

Real Samples ◽

Cow's Milk ◽

Milk Samples ◽

Raw Cow’S Milk

Simazine is an herbicide that is able to contaminate surface waters, ground waters, and milk/dairy products, thus posing concerns in both environmental health and food safety. A yeast-based bioprobe was utilized to detect simazine in spiked real samples of livestock drinking water and raw cow’s milk. Yeast aerobic respiration was taken as short-term toxicological endpoint. We carried out comparative measures of yeast oxygen consumption between simazine-spiked samples and blank samples. Percentage interference (%ρ) on yeast aerobic respiration was calculated through the comparison of aerobic respiration of simazine-exposed and non-exposed yeast cells. The method was optimized for raw cow’s milk samples by using boric acid as fungistatic agent in order to avoid cellular proliferation. Overall, the results have shown that simazine can be detected up to concentrations five times below the EU legal concentration limits for drinking water (0.02 ppb) and cow’s milk (2 ppb) (%ρ values of 18.53% and 20.43% respectively; %RSD ≤ 15%). Dose-effect relationships of simazine were assessed. The findings of the bioassays match reasonably well with known mechanisms of toxicity and intracellular detoxification in yeast. A correlation between fat content in milk samples and analytical performance of the bioprobe was established. Results suggest the involvement of a matrix effect, presumably due to lipid sequestration of simazine. The yeast-based bioprobe has proved to be sensitive and suitable for the detection of simazine in real samples in concentrations of interest.

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Detection of Aflatoxin M1 in Human Breast Milk and Raw Cow's Milk in Istanbul, Turkey

Journal of Food Protection ◽

10.4315/0362-028x-72.4.885 ◽

2009 ◽

Vol 72 (4) ◽

pp. 885-889 ◽

Cited By ~ 32

Author(s):

YAŞAR KESKIN ◽

RUHTAN BAŞKAYA ◽

SEHER KARSLI ◽

TÜRKAN YURDUN ◽

OĞUZ ÖZYARAL

Keyword(s):

Breast Milk ◽

High Performance ◽

Aflatoxin M1 ◽

Cow’S Milk ◽

Enzyme Linked Immunosorbent Assay ◽

Human Breast Milk ◽

Human Breast ◽

Cow's Milk ◽

Milk Samples ◽

Raw Cow’S Milk

This survey was undertaken to determine the extent of aflatoxin M1 (AFM1) contamination in human breast milk and raw cow's milk in Istanbul, Turkey. Samples of human and raw cow's milk were collected randomly and analyzed for AFM1 using an enzyme-linked immunosorbent assay and high-performance liquid chromatography with fluorescence detection in which the samples were cleaned up with immunoaffinity columns. In this study, AFM1 was detected in 8 (13.1%) of 61 human breast milk samples examined (mean ± SD level, 5.68 ± 0.62 ng/liter; range, 5.10 to 6.90 ng/liter) and 20 (33.3%) of 60 raw cow's milk samples examined (range, 5.40 to 300.20 ng/liter). Five (8.3%) of the positive raw cow's milk samples had AFM1 levels (153.52 ± 100.60 ng/liter; range, 61.20 to 300.20 ng/liter) that were higher than the maximum tolerance limit (0.05 ppb) stipulated by regulations in Turkey and some other countries.

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