Cow Milk Samples Research Articles

Dispersive solid phase extraction-dispersive liquid–liquid microextraction of mycotoxins from milk samples and investigating their decontamination using microwave irradiations

Metal organic framework based dispersive solid phase extraction combined with dispersive liquid–liquid microextraction has been developed for the extraction of aflatoxin M1 and ochratoxin A from milk samples. The analytes were determined by high performance liquid chromatography–fluorescent detector. After optimization of the effective parameters, the analytical characters of method were studied. Based on the data, the proposed method provided satisfactory results such as low limits of detection (0.25 and 0.37 ng L–1 for ochratoxin A and aflatoxin M1, respectively) and quantification (0.83 and 1.23 ng L–1), high extraction recoveries (87 and 75%) and enrichment factors (305 and 263), and good repeatability (relative standard deviations equal or less than 4.9 and 5.1% for intra– and inter day precisions, respectively). After validation the method, the suggested approach was applied for the quantification of the aflatoxin M1 and ochratoxin A in various raw cow's milk samples and the effect of microwave irradiations in decontaminating them from milk samples were studied.

Functional Characterization of Lactobacillus plantarum Isolated from Cow Milk and the Development of Fermented Coconut and Carrot Juice Mixed Beverage.

Screening probiotics are crucial for assessing their safety, security, and further production of functional foods for human health. The present study aimed to isolate and identify bacteria from raw cow's milk samples that exhibit health benefits upon consumption. We characterized the probiotic properties of Lactobacillus plantarum (also called Lactiplantibacillus plantarum) strains CMGC2 and CMJC7 isolated from cow milk by in vitro study. The strains exhibited tolerance to simulated gastric conditions and were further identified by 16S rRNA sequencing as Lactobacillus plantarum (L. plantarum) CMGC2 and CMJC7. Both isolates were evaluated in vitro for their probiotic attributes, viz. hydrophobicity, autoaggregation, co-aggregation, lysozyme tolerance, antibacterial activity, antibiotic susceptibility, hemolytic activity, and phenol tolerance. The isolates CMGC2 and CMJC7 showed excellent probiotic attributes; hence, both strains were selected to produce coconut and carrot juice mixed beverages (CCMB). The CCMB was evaluated for the pH, acid-production rate, and total viable bacterial counts. The results showed that the CCMB was an excellent medium for the growth of CMGC2 and CMJC7 as it supported adequate growth of organisms (8.93CFU/mL and 8.68CFU/mL, respectively) even after 48h of incubation. In conclusion, CMGC2 and CMJC7 can be used to develop different beverages possessing nutritive and probiotic values, and these beverages can be used for producing unique products.

Antimicrobial and anti-biofilm effects of carotenoid pigment extracted from Rhodotorula glutinis strain on food-borne bacteria.

Carotenoid pigments are among the most important pigments and have many applications in various food, cosmetics, hygiene industries and biotechnology. These pigments are produced by plants and microorganisms including Rhodotorula spp. This research intended to study the antimicrobial and antibiofilm effects of the carotenoid pigment from Rhodotorula glutinis on food spoilage bacteria (Staphylococcus aureus and Salmonella Typhimurium). The R. glutinis was isolated from milk samples of cows with mastitis and ITS sequence-based typing was performed on them. After extracting the pigment from R. glutinis, its purity was examined using thin-layer chromatography. Following that, the broth microdilution method was used to evaluate antimicrobial effects of the pigment and MtP assay and subsequently scanning electron microscopy were used to assess the antibiofilm effects. In addition, the sub-MIC effects of the pigment on expression of quorum-sensing (QS) genes in S. Typhimurium isolates (sdiA and luxS) and S. aureus isolates (hld) were studied. Finally, the degree of toxicity of the pigment was analyzed using the MTT assay. ITS sequence analysis of R. glutinis revealed that the recently separated isolates exhibited strong differences with the strains recorded in NCBI database in genetic structure. The pigment produced by R. glutinis had strong antimicrobial effects and its mean MIC against S. Typhimurium isolates (17.0 μl.ml-1) was higher than the mean MIC against the S. aureus isolates (4.1 μl.ml-1). Electron microscope images and real-time observations indicated that the sub-MIC values of the pigment suppressed biofilm formation by suppressing expression of QS genes. In addition, the mentioned pigment at high MIC concentrations did not have toxic effects on Vero cells. This research suggests that R. glutinis pigment is effective in destroying the planktonic form of food spoilage bacteria and degrading food spoilage biofilm-forming bacteria. Moreover, considering the low toxicity level of R. glutinis pigment for eukaryotic cells, we can suggest its use as a natural antibacterial preservative in various food materials.

Detection of Soybean-Derived Components in Dairy Products Using Proofreading Enzyme-Mediated Probe Cleavage Coupled with Ladder-Shape Melting Temperature Isothermal Amplification (Proofman–LMTIA)

Food adulteration is a serious problem all over the world. Establishing an accurate, sensitive and fast detection method is an important part of identifying food adulteration. Herein, a sequence-specific ladder-shape melting temperature isothermal amplification (LMTIA) assay was reported to detect soybean-derived components using proofreading enzyme-mediated probe cleavage (named Proofman), which could realize real-time and visual detection without uncapping. The results showed that, under the optimal temperature of 57 °C, the established Proofman-LMTIA method for the detection of soybean-derived components in dairy products was sensitive to 1 pg/μL, with strong specificity, and could distinguish soybean genes from those of beef, mutton, sunflower, corn, walnut, etc. The established Proofman-LMTIA detection method was applied to the detection of actual samples of cow milk and goat milk. The results showed that the method was accurate, stable and reliable, and the detection results were not affected by a complex matrix without false positives or false negatives. It was proved that the method could be used for the detection and identification of soybean-derived components in actual dairy products samples.

Detection of multidrug-resistant Staphylococcus aureus isolated from dairies milk in Medowo Village of Kediri District, Indonesia

Abstract. Putra GDS, Khairullah AR, Effendi MH, Lazuardi M, Kurniawan SC, Afnani DA, Silaen OSM, Waruwu YKK, Millannia SK, Widodo A, Ramadhani S, Farizqi MTI, Riwu KHP. 2023. Detection of multidrug-resistant (MDR) Staphylococcus aureus isolated from dairies milk in Medowo Village of Kediri District, Indonesia. Biodiversitas 24: 423-430. Bacterial resistance has emerged as a major concern in dairy farms in Indonesia due to the pervasive usage of antibiotics. Furthermore, no specific research has been done to explain the prevalence of Staphylococcus aureus in isolated milk from dairy cows in Kediri, particularly in Medowo Village, and their antibiotic resistance. Moreover, to control the emergence of diseases in humans brought on by dairy cow's milk or infections transmitted through milk, additional research on the prevalence and resistance of bacteria in dairy farms in the Kediri district is urgently required. In Medowo, the Village Kandangan of District, Kediri Regency, Indonesia, 100 dairy cow's milk samples were taken from farms in numerous hamlets. The Kirby-Bauer method performed an antibiotic sensitivity test using disk diffusion. The sensitivity test was attached with antibiotic discs on tetracycline, penicillin, gentamicin, erythromycin, and cefoxitin. According to sample evaluation results, S. aureus was detected in 94 (94%) of the 100 isolated milk samples based on morphological culture features, Gram staining, and biochemical assays. According to the profile of antibiotic resistance derived from the findings of the S. aureus antibiotic resistance test, 23 isolates (24.47%) were proven to be multidrug-resistant (MDR) because they were resistant to three to four classes of antibiotics. The use of antibiotics typically rises in response to an increase in the prevalence of disease in cattle, which could lead to higher levels of antibiotic residue in milk and possibly higher levels of bacterial resistance to antibiotics. Therefore, dairy farming requires methods for prudently and correctly employing antibiotics.

Biofilm expression and antimicrobial resistance patterns of Streptococcus uberis isolated from milk samples of dairy cows in South Africa.

The research described in this Research Communication addresses the hypothesis that intramammary infections with Streptococcus uberis (S. uberis) are associated with biofilm formation, which limits antibiotic efficacy. This retrospective study investigated biofilm expression and antimicrobial resistance (AMR) patterns of 172 S. uberis infections. Isolates were recovered from milk samples of subclinical, clinical, and intramammary infection cases on 30 commercial dairy herds. We determined the presence and intensity of biofilm expression of S. uberis isolates in vitro in three somatic cell count categories to recognise their AMR patterns. An automated minimum inhibitory concentration system with a commercially available panel of 23 antimicrobial agents evaluated AMR, while biofilm determination was conducted using a microplate method. The study established that all the S. uberis isolates assessed expressed biofilm with the following varying degrees of intensities: 30 (17.8%) strong, 59 (34.9%) medium and 80 (47.3%) weak biofilms. The newly registered UBAC mastitis vaccine containing biofilm adhesion components may, therefore, be a viable option for proactive mastitis management under field conditions. No differences were identified between biofilm intensity and the three somatic cell count groups. Most S. uberis isolates indicated a high-level sensitivity to the antimicrobial agents tested. Resistances were present in 8.7, 8.1 and 7.0% cases to rifampin, minocycline and tetracycline, respectively. Multidrug resistance was observed in 6.4%, emphasising AMR to antibiotics used in human medicine only. The low overall resistance suggests that farmers adhere to the prudent use of antimicrobials in the dairy industry.

Replacing alfalfa hay with industrial hemp ethanol extraction byproduct and Chinese wildrye hay: Effects on lactation performance, plasma metabolites, and bacterial communities in Holstein cows.

This trial was designed to investigate the effects of industrial hemp ethanol extraction byproduct (IHEEB) and Chinese wildrye hay (CWH) replacement of alfalfa hay (AH) on digestibility, and lactation performance, plasma metabolites, ruminal fermentation, and bacterial communities in Holstein dairy cows. Nine healthy multiparous Holstein cows (parity = 3) with similar body weights (584 ± 12.3 kg), days in milk (108 ± 11.4), and milk yields (30 ± 1.93 kg; all mean ± standard deviation) were used in a replicated 3 × 3 Latin square design with 3 periods of 21 d. During each period, each group consumed 1 of 3 diets: (1) 0% IHEEB (0IHEEB); (2) 6.0% IHEEB and 1.7% Chinese wildrye hay (6IHEEB); (3) 10.8% IHEEB and 4.3% Chinese wildrye hay (11IHEEB). The diets in each group were isocaloric and isonitrogenous, with similar contents of concentrate and silage but different ratios of IHEEB and CWH to replace AH. The results showed that increasing the substitute did not affect the total-tract apparent nutrient digestibility. There was no difference in lactation performance of dairy cows fed the three diets, except for the cows' somatic cell count (SCC), which decreased with the increase in the amount of the substitute. Cannabidiol and tetrahydrocannabinol were not detected in milk samples of dairy cows in the different treatment groups. 6IHEEB and 11IHEEB-fed cows showed a linear decrease in total volatile fatty acids (VFA) and butyrate compared to the 0IHEEB cows. Plasma IL-1β content quadratically decreased with feeding IHEEB and CWH, and other blood parameters were unaffected. The rumen fluid's relative abundances of Bacteroidota, Fibrobacterota, and Prevotellaceae quadratically increased, while Firmicutes tended to decrease quadratically as the substitution increased. Feeding IHEEB and CWH linearly increased the relative abundances of Firmicutes, Lachnospiraceae, Monoglobaceae, and Butyricicoccaceae in the feces. As the substitution increased, the cost of dairy farming was reduced. In summary, substituting AH with IHEEB and CWH in diets did not affect the total-tract apparent nutrient digestibility, improved milk composition, and plasma immune indices. It changed the bacterial composition in rumen fluid and feces and improved dairy farming benefits.

A Sensitive and Selective Electrochemical Aptasensor Based On Gold Nanoflower/Polyethyleneimine (Pei)-Functionalized Metal Organic Framework Nanocomposites for Label-Free Determination of Streptomycin in Milk Samples

Rapid, accurate, sensitive, and real-time detection of streptomycin (STR) residues in dairy products is very important. In this work, for the first time, the gold nanoflower/polyethyleneimine-functionalized metal organic framework (AuNF-PEI-MIL-101(Cr)) nanocomposites were synthesized via hydrothermal method and characterized using various techniques (SEM, TEM, XRD, FT-IR, and XPS). Then, a novel electrochemical aptasensor was constructed for the detection of STR based on AuNF-PEI-MIL-101(Cr) nanocomposites. The gold electrode (GE) modified with AuNF-PEI-MIL-101(Cr) can immobilize a large number of thiolated STR aptamer via the Au–S bond. When the target STR was in the presence, the current signal was reduced due to the specific binding of STR towards the aptamer. The results indicated that the aptasensor had a wide linear range towards STR (0.01–400 nM) with a low detection limit of 0.003 nM under the optimal conditions. Moreover, the aptasensor exhibited good selectivity, reproducibility, and stability. In addition, the STR in the cow, sheep, and goat milk samples was detected by the spiked recovery method, and satisfactory results were obtained. The method provides an efficient pathway for the sensitive detection of STR.

The Effective Dose Equivalent for potassium K40 in Cow's Milk of Salah-Din Governorate/ Iraq

Radioactivity was measured for 170 cow's milk samples in Salah-Din governorate. Samples were measured by a gamma spectrometry system, using a high purity germanium (HPGe) detector. The detector was shielded by 10 cm all sides with cadmium copper in the inner sides. The selected characteristic gamma peaks for the detection of different ware 1460kev for K-40. The energy calibration was performed using a set of standard gamma ray calibration sources Eu-152. The results of show the presence of in all samples of milk. The maximum radioactivity was seen in Baiji city was (424 Bq/kg), while the minimum was seen in Abayaji (256 Bq/kg) and the average of all samples was (341.3 Bq/kg) and the annual effective dose was 0.302`mSv/y.That considered as the annual limit of rang of public recommended by the FAO.
 

Handling, Processing and Composition of Cow Milk Under Two Traditional Farming Systems in Kebribeyah District of Fafan Zone, Somali Regional State, Ethiopia

The aim of this study was to assess handling, processing & chemical composition of cow milk in Kebribeyah district. The study had a survey and laboratory works. For the survey study, two production systems namely pastoral and agro-pastoral were considered. From each production system, two kebeles were selected purposively based on accessibility and potential of cow milk production. One hundred twenty households were randomly selected from purposively selected kebeles. For the laboratory part, forty samples of cow milk were analysed for chemical composition. The overall average lactation length and daily milk off-take of cow in this study were 256 days and 2.06 litres, respectively. None of the respondents washed the udder of the cow and only 6.7% of the pastoralists and 20% agro-pastoralists wash their hands before milking. Milk handling equipment were mainly plastic materials. Acacia ethaica, B. minimifolia, Blanites galabra and Solanum carense were the most commonly used smoking plant species in the area. The majority of the respondents (85.8%) produced traditional butter (Subag) and few households (10%) produced sour milk (Ciir), while very few (4.2%) households produced traditional cheese (Burcad). However, milk processing in the area is limited to wet season; when there is abundance of fodder. The average values of total solids, fat, protein, lactose and ash were 13.19%, 4.67%, 3.45%, 5.18% and 0.72%, respectively. However, significance differences (P<0.05) were found between pastoral and ago-pastoral production systems in terms of total solids, fat, and protein. The chemical properties of milk samples obtained from pastoral and agro-pastoral areas were within the acceptable standard levels settled by different scholars. In general, milk producers should also be supported with strong extension service by way of introducing improved dairy technologies, improved milk handling and processing equipments. Furthermore, there is a need for further investigations on composition with various farming systems.

Changes in the total amount of antioxidants in cow milk with milking time at the peak of lactation

Relevance. Milk contains a large number of biologically active compounds (including antioxidants) and is deservedly considered one of the main food products both in its original form and after technological processing. Materials and methods. In this work, the measurements of the total amount of antioxidants (TOA) in milk samples of cows (from the «Ladozhskoye» breeding farm) at the peak of lactation were carried out by the amperometric method, and milk parameters during morning and evening milking were assessed by classical methods. Results. As a result of the study, new data of TOA were obtained for 38 milk samples of Black-and-White breed cows of 5 groups depending on the lactation period: 1) 151–165 days; 2) 166–180 days; 3) 181–210 days; 4) 211–225 days; 5) 226–240 days, respectively. Moderate and strong correlations were obtained between TOA data and single milk yields (morning and evening milking), which are not only fundamentally new, but also important for assessing the total antioxidant activity in certain periods of lactation. Since the level of antioxidants significantly affects the shelf life, nutritional value, and many other parameters of milk, the authors suggest using the TOA level as an additional parameter in the overall assessment of milk quality. The data obtained are of great importance in assessing the physiological-biochemical status, including the state of the system of antioxidant defense of the body of cows.

Antimicrobial efficacy of Thymus vulgaris extract against some Staphylococcus species isolated from subclinical mastitis in cattle in Basrah province, Iraq.

Thymus vulgaris extracts can play a significant role as alternatives for antimicrobial agents against bovine staphylococcus mastitis. This research's goal was to evaluate the antibacterial properties of an extract from T. vulgaris as an alternative to antibiotics for bovine Staphylococcus mastitis. In addition, it is important to know the effect of the extraction methods (hot alcoholic, cold alcoholic, and hot water extract) on their effectiveness. Two hundred ten cow milk samples from different areas of Basrah province had been suffering subclinical mastitis reported by using the California mastitis test (CMT). Staphylococcus species were identified by conventional microbiological technique, GP24 Kit, and nuc gene. Antimicrobial activity of various concentrations of T. vulgaris extracted (75, 50, 25) mg/ml with different methods of extraction (hot alcoholic, cold alcoholic, and hot water extract). Out of 210 samples, 99 (47.1%) were positive for the CMT, and the identification rate of Staphylococci spp. by conventional microbiological technique and GP24 kit was 78 (78.8%). Out of 78 isolates of Staphylococcus spp. 48 (61.5%) were identified as Staphylococcus aureus, by using both molecular techniques using PCR and miniaturized Kit GP24 and employing the miniature GP24, the remaining 30 (38.5%) were determined to be different species of Staphylococcus. Antibacterial activity of various concentrations of T. vulgaris extracted (75, 50, 25) mg/ml with different methods of extraction revealed that hot alcoholic extract (100%) was more effective than cold alcoholic extract (66.7%), whereas there is no effect on the bacteria species with the hot water extract. Thymus vulgaris extracts can play a significant role as alternatives for antimicrobial agents against bovine staphylococcus mastitis.

Detection of Antimicrobial Drug Residues in Raw Cow Milk samples in Logar and Maidan Wardak Province, Afghanistan

Background: Nowadays, various types of antibiotics are being used worldwide in the veterinary sector particularly, for the promotion of growth and treatment of livestock. Significant portions of antibiotics are released through the milk of dairy animals inviolate and exert serious harmful effects on human health. Milk that utilizes by human consumption should also comply with safety criteria regarding antibiotic residues. The objective of this study was to determine the level of antibiotic residues in raw milk conferred by the milk producer’s cooperatives of Logar and Maidan Wardak provinces to Guzargah dairy union for further processing and distribution. Materials and Methods: In this research 110, raw cow milk samples for a one-year period were collected and analyzed (n=110). 55 samples were collected from Logar province and 55 samples were collected from Maidan Wardak province. Milk samples were tested by Betastar Combo Test Kit. All samples considering the laboratory procedures were transported to the laboratory and tested for the presence of Tetracycline and Beta lactams as these antibiotics are widely used for the treatment of bovine mastitis. Finding: Out of 110 milk samples, 12 samples were positive for the presence of Tetracycline residues and 7 samples were positive for the presence of Beta lactams. For further accuracy of the result, all the positive samples were tested by Microbial Inhibition Assay (MIA), and the same result is obtained. Conclusion: The study results show and indicate that antibiotic residues are present in the samples which paves the way for the contamination of human food chains. Considering that milk is mostly consumed by the elderly and kids, hence, it can be the main concern for public health.

Screening of beef and raw cow milk from central Kerala for Campylobacter spp. using multiplex PCR

Campylobacter spp. is considered one of the leading causes of diarrhoeal disease. Due to the prevalence of this organism in the gut microbiota of all warm-blooded animals, the chance of contamination is more through animal products. The present study was conducted to assess the occurrence of Campylobacter spp. in milk and beef of central Kerala. A total of 200 beef and 200 raw cow milk samples were collected from various retail outlets and milk societies of Thrissur and Ernakulam districts. Campylobacter spp. were isolated by conventional culture technique on Modified charcoal-cefoperazone-deoxycholate agar. A molecular technique targeting the genusspecific 16S rRNA gene further confirmed the culture and biochemically positive isolates. The species-specific mapA and ceuE genes were targeted for C. jejuni and C. coli, respectively. None of the milk samples collected were positive for Campylobacter spp. However, three per cent of beef samples were tested positive for Campylobacter spp.

Occurrence of Klebsiella pneumoniae and Salmonella spp. in beef and cow milk from central Kerala

Klebsiella pneumoniae is a clinically important opportunistic pathogen and Salmonella spp. is a major food-borne pathogen causing gastroenteritis worldwide. The present study was conducted to determine the occurrence of K. pneumoniae and Salmonella spp. in beef and cow milk collected from central Kerala. The study was conducted in a span of 10 months from, January 2022 to October 2022. A total of 400 samples, comprising of 200 raw cow milk samples and 200 beef samples, were collected from different milk societies and retail shops of Thrissur and Palakkad districts. The K. pneumoniae and Salmonella spp. were isolated by conventional culture techniques on MacConkey agar and Xylose lysine deoxycholate agar, respectively. When conventional culture technique was used, 57.50 per cent and 10.25 per cent samples were positive for K. pneumoniae and Salmonella spp., respectively. The molecular confirmation of K. pneumoniae was carried out by PCR targeting genus specific gyrA followed by species specific rpoB gene. Salmonella spp. was confirmed on PCR by amplifying species specific invA gene and spvC gene was targeted to evaluate the virulent nature of the isolates. Out of the 400 milk and beef samples analysed 50.75 per cent were positive for K. pneumoniae and 10.25 per cent were positive for Salmonella spp. Implementation of standard hygiene practices during production, distribution chain are required to avoid the contamination of milk and beef samples indented for human consumption.

Burdur İli Çiğ İnek Sütü Örneklerinde Aflatoksin M1 Kalıntısının İncelenmesi

Bu çalışma, gıdalarda aflatoksin bulunmasından kaynaklanan ekonomik kayıplar ve halk sağlığı endişeleri nedeniyle aflatoksin M1 (AFM1) düzeyini belirlemek amacıyla yapılmıştır. Burdur ilindeki çiftliklerden toplam 82 çiğ inek sütü örneği rastgele alındı ve Enzyme-Linked Immunosorbent Assay (ELISA) yöntemi kullanılarak AFM1 açısından analiz edildi. İncelenen 82 çiğ inek sütü örneğinin 48'inde (%58,5) AFM1 seviyesinin 5,06 ila 50,63 ng kg-1 arasında ve ortalama kontaminasyon oranının 15,53 ±1,49 ng kg-1 olduğu tespit edildi. Süt örneklerinin 1'inde (%1,2) AFM1 düzeyi Türk Gıda Kodeksi ve AB Yönetmeliği'nde belirtilen yasal sınırların üzerinde olduğu belirlendi. Sonuç olarak çiğ süt örneklerinde belirlenen AFM1 seviyesi maksimum kalıntı limitlerinin altında ve insan tüketimine uygun bulunmuştur. Ayrıca Türkiye'deki yetişkin tüketici için AFM1'in tahmini günlük alım miktarı (EDI) belirlenmiştir. Yetişkin tüketicinin ortalama EDI'si (0,19 ng kg-1 vücut ağırlığı gün-1), önerilen günlük 0,2 ng kg-1 vücut ağırlığı gün-1 AFM1 alımına yakın bulunmuştur. Ancak bu konudaki çalışmaların düzenli bir program dahilinde tekrarlanması ve hem üreticilerin hem de tüketicilerin konu hakkında bilgilendirilmesi önerilmektedir.

Characterization of mammary pathogenic Escherichia coli reveals the diversity of Escherichia coli isolates associated with bovine clinical mastitis in Brazil

Mammary pathogenic Escherichia coli (MPEC) is one of the most common pathogens associated with clinical mastitis. We analyzed isolates obtained from milk samples of cows with clinical mastitis, collected from 10 farms in Brazil, to verify molecular and phenotypic characteristics. A total of 192 (4.5%) mammary pathogenic E. coli isolates were obtained from 4,275 milk samples analyzed, but we tested 161. We assigned most of these isolates to E. coli phylogroups B1 (52.8%) and A (36.6%), although phylogroups B2, C, D, E, and unknown also occurred. All isolates were assessed for the presence of several genes encoding virulence factors, such as adhesins (sfaDE, papC, afaBC III, ecpA, fimH, papA, and iha), toxins (hlyA, cnf1, sat, vat, and cdt), siderophores (iroN, irp2, iucD, ireA, and sitA), an invasion protein (ibeA), and serum resistance proteins (traT, KpsMTII, and ompT), and isolates from phylogroups B1, B2, and E showed up to 8 genes. Two isolates harbored the locus of enterocyte effacement (escN+) and lack the bundle-forming pilus (bfpB-) operon, which corresponds to a molecular profile of a subgroup of diarrheagenic E. coli (aEPEC), thus being classified as hybrid MPEC/aEPEC isolates. These isolates displayed a localized adherence-like pattern of adherence in HeLa cells and were able to promote F-actin polymerization underneath adherent bacteria. Based on the pulsed-field gel electrophoresis analyses, considerable genetic variability was observed. A low index of antimicrobial resistance was observed and 2 extended-spectrum β-lactamase-producing E. coli were identified, both harboring blaCTX-M15 gene, and were classified as ST10 and ST993 using multilocus sequence typing. A total of 148 (91.2%) isolates were weak biofilm producers or formed no biofilm. Because raw milk is still frequently consumed in Brazil, the occurrence of virulence factor-encoding genes from extraintestinal or diarrheagenic E. coli added to the presence of extended-spectrum β-lactamase-producing isolates can turn this veterinary medicine problem into a public health concern.

Investigation of Beta-lactam Group Antibiotics Residue in Raw Cow Milk in Sivas Province

In this study, beta-lactam group antibiotic residues were investigated in raw cow's milk. For this purpose, a total of 86 raw milk samples were used as material. Samples were collected periodically from farms in various outlets and surrounding villages in the province of Sivas. Beta-lactam group antibiotic levels in raw cow's milk were determined by ELISA method with commercial test kit. According to the analysis results, beta-lactam levels were between 0.35-0.70 ng/mL in 64 (74.4%) and between 0.71-3.7 ng/mL in 22 samples (25.6%) determined of 86 raw cow milk samples. The residue levels detected in the samples are in accordance with the legal limits declared by the European Union (EU) commission and Turkish Food Codex Communique.

Occurrence of Aflatoxin M1 in Cow, Goat, Buffalo, Camel, and Yak Milk in China in 2016.

In this present study, 195 cow milk, 100 goat milk, 50 buffalo milk, 50 camel milk, and 50 yak milk samples were collected in China in May and October 2016. The presence of aflatoxin M1 (AFM1) was determined using enzyme-linked immunosorbent assay method. For all cow milk samples, 128 samples (65.7%) contained AFM1 in concentrations ranging from 0.005 to 0.191 µg/L, and 6 samples (3.1%) from Sichuan province in October were contaminated with AFM1 above 0.05 µg/L (EU limit). For all goat milk samples, 76.0% of samples contained AFM1 in concentrations ranging from 0.005 to 0.135 µg/L, and 9 samples (9.0%) from Shanxi province in October were contaminated with AFM1 above 0.05 µg/L. For all buffalo milk samples, 24 samples (48.0%) contained AFM1 in concentrations ranging from 0.005 to 0.089 µg/L, and 2 samples collected in October were contaminated with AFM1 above 0.05 µg/L. Furthermore, 28.0% of samples contained AFM1 in concentrations ranging from 0.005 to 0.007 µg/L in camel milk samples, and 18.0% of samples contained AFM1 in concentrations ranging from 0.005 to 0.007 µg/L in yak milk samples. Our survey study has expanded the current knowledge of the occurrence of AFM1 in milk from five dairy species in China, in particular the minor dairy species.

Isolation of Lactococcus garvieae NEP21 from raw cow (Bos indicus) milk in Nepal

Lactococcus garvieae is an emerging zoonotic pathogen impacting both humans and animals. Infection of this bacterium is known to cause mastitis in cattle, and endocarditis, osteomyelitis, liver abscess, and gastrointestinal problems are reported in immunocompromised and elderly people that regularly consume or handle raw meat, milk, dairy products, and seafood. This study aimed at investigating and detecting lactic acid bacteria in raw cow (Bos indicus) milk samples from a smallholder farm in Nepal. Based on the plate culture, biochemical tests, and molecular sequencing of 16 s ribosomal RNA coding nuclear DNA region followed by phenotypic and genotypic analyses, L. garvieae NEP21 was detected and identified for the first time in Nepal in raw cow milk samples. This finding suggests the prevalence of L. garvieae NEP21 in raw cow milk and recommends further research and surveillance for understanding the extent of its presence in Nepal and globally for informed management of its infection in cattle and humans.