Goat Milk Samples Research Articles

Molecular insights into antimicrobial resistant Staphylococcus aureus strains: A potential zoonosis of goat origin

Antimicrobial-resistant (AMR) Staphylococcus aureus (S. aureus) strains have attained global attention due to their life-threatening zoonotic nature. Being a member of ESKAPE group, S. aureus has an ability to escape the biocidal action of antimicrobial drugs. The current study investigated the prevalence and molecular characterization of methicillin-resistant S. aureus (MRSA), β-lactam-resistant S. aureus (BRSA), aminoglycoside-resistant S. aureus (ARSA), tetracycline-resistant S. aureus (TRSA), and fluoroquinolones-resistant S. aureus (FRSA) associated with goat subclinical mastitis (SCM). Furthermore, the antimicrobial resistance and susceptibility profile of various antibiotics and non-antibiotics (NSAIDs, nisin, N-acetylcysteine, vitamin-C) along with their possible role in modulating the antibiotic resistance of MDR isolates was also investigated. A total of 768 goat milk samples were subjected to California mastitis test for SCM followed by bacteriological and molecular characterization of S. aureus. Moreover, in-vitro susceptibility of resistant antibiotics, non-antibiotics, and their combination against MDR S. aureus were conducted through well diffusion and broth microdilution assays. The results depicted that 55.47% and 26.82% of milk samples were positive for SCM and S. aureus, respectively. The molecular assay confirmed 35.92% of isolates as MRSA, 45.63% as BRSA, 50.49% as ARSA, and 32.52% but no isolate was confirmed as FRSA on molecular basis. The multidrug resistance was observed in 62.13% and 47.09% isolates, respectively. Molecular characterized MDR S. aureus revealed high homology of study isolates with the isolates of neighboring countries like India, Korea, Iran, and China. Antimicrobial susceptibility trials on well diffusion assay showed higher efficacy of different non-antibiotics with resistant antibiotics as penicillin with ketoprofen and gentamicin with flunixin meglumine while oxytetracycline with N-acetylcystiene. The synergy testing by checkerboard assay revealed synergistic activity of penicillin with ketoprofen, gentamicin with flunixin meglumine, and oxytetracycline with N-acetylcysteine. The current study highlighted the emergence and spread of AMR S. aureus strains from goat SCM and provided insights into possible drug repurposing of various non-antibiotics to modulate the multidrug resistance of S. aureus which will be helpful in devising the therapeutic options and control measures for this pathogen.

Folic acid, cobalamin, and biotin concentrations in milk samples of sheep, goats, and cows

Milk is an important food obtained from mammals, containing almost all of the nutrients needed for metabolism. The vitamin composition of milk, the first food of mammals, is valuable data for the food industry and public health. This study aimed to determine the levels of folic acid (vitamin B9), cobalamin (vitamin B12), and biotin (vitamin B7) in different milk samples (cow, sheep, goat) using the ELISA method. For this purpose, milk samples from Holstein Cows (n:50), Awassi Sheep (n:50), and Kilis Goats (n:50) available for retail in the Şanlıurfa province of Turkey were collected and analyzed. In this study, the average folic acid content of sheep, goat, and cow milk was found to be 3.45 µg/100 mL, 7.23 µg/100 ml, and 6.64 µg/100 mL, respectively. The average cobalamin content of sheep, goat, and cow milk was 0.70 µg/100 ml, 7.43 µg/100 ml, and 0.58 µg/100 mL, respectively, while the average biotin content of sheep, goat, and cow milk was 2.21 µg/100 mL, 2.21 µg/100 mL, and 2.09 µg/100 mL, respectively. It was noted that the average biotin levels in sheep, goat, and cow milk did not differ significantly. However, significant differences were observed in the quantities of folic acid and cobalamin (P<0.05). Different levels of folic acid were found in milk samples from these three species. Cobalamin levels in goat milk samples were significantly higher, while biotin levels were similar in each milk sample of the species. This study underscores the importance of understanding and considering the diverse vitamin compositions of milk from different mammalian species to ensure comprehensive nutritional intake.

Hygienic-sanitary quality in family farm goat milk production

Dairy goat farming became on a profitable activity for small and medium family producers. Thus, goat milk constitutes excellent culture media for the development of undesirable, spoiling and pathogenic microorganisms. Thus, the present study evaluated the microbiological quality of goat milk and dairy derivatives, in order to provide family farmers support and encouragement to adoption of food safety in production chain. A total of 25 samples were evaluated, including refrigerated raw goat milk, goat cheese with or without spices and goat milk caramel. Microbiological analyzes included mesophilic and psychrotrophic bacteria, total coliforms and Escherichia coli, Staphylococcus aureus, yeast and molds enumeration and Salmonella spp detection. Mesophilic and psychrotrophic bacteria, total coliforms and fungi enumerations of most goat milk and cheese samples presented values above the limit established by Brazilian legislation. In only five samples Staphylococcus aureus were detected, being four of goat milk and one of cheese, and most of the isolates were susceptible to antimicrobials of animal and human use. All samples were absent to Salmonella spp.. Goat milk caramel was the best microbiological profile product.

Development of a cell culture-based method for detecting infectious tick-borne encephalitis virus (TBEV) in milk products

Tick-borne encephalitis outbreaks have been reported in Europe after consumption of raw milk products from infected animals. While molecular methods are commonly used in viral foodborne outbreak investigations due to their sensitivity, specificity and rapidity, there are very few methods to detect infectious tick-borne encephalitis virus (TBEV) in milk products for routine use/analyses. To address this gap, we developed a cell culture-based method to detect infectious TBEV in artificially contaminated raw goat milk and raw goat cheese, and evaluated the sensitivity of TBEV infectivity assays. Raw goat milk samples were spiked with TBEV to achieve inoculation levels ranging from 106 to 100 TCID50/mL, and Faisselle and Tomme cheese samples were spiked so their TBEV concentrations ranged from 9.28 × 105 to 9.28 × 101 TCID50 per 2.5g. To detect infectious TBEV, Vero cells were infected by raw goat milk. For cheese samples, after homogenisation and membrane filtration, Vero cells were infected with samples adsorbed on the filter (method A) or with samples eluted from the filter (method B). After 5 days, cytopathic effects (CPEs) were observed and TBEV replication in Vero cells was confirmed by an increase in the number of genome copies/mL that were detected in cell supernatant. Infected Vero cells exhibited CPEs for both milk and cheese samples. Infectious TBEV was detected to 103 TCID50/mL in raw milk samples and to 9.28 × 101 TCID50 from Faisselle samples using both methods A and B. For Tomme samples, method A was able to detect TBEV to 9.28 × 102 TCID50/2.5g and method B to 9.28 × 103 TCID50/2.5g. The number of positive samples detected was slightly higher with method A than with method B. To conclude, this qualitative cell culture-based method can detect infectious TBEV artificially inoculated into raw milk and cheese; it should be further evaluated during foodborne outbreak investigations to detect infectious TBEV from naturally contaminated milk and cheese.

Isolation and Molecular Characterization of Therapeutic Probiotic Lactobacillus from Different Sources in Ernakulam-Kerala

This study aims to present knowledge on therapeutic potential bacteriocin producing bacterial strains. Samples (n=35) from diverse Ernakulam sources yielded 26 lactic acid bacteria (LAB) isolates on De Man Rogosa Sharpe (MRS) medium. Among the isolates potent antimicrobial activity observed against known pathogens in one of the isolates from goat milk sample number 3, labelled as GO3. Microscopic and biochemical test revealed the isolate is Gram-positive rod, non-sporulating and resilience to pH and bile salts, with adaptability to gastric enzymes and surfactants. Genetic and physiological traits of the positive strains were confirmd by 16S rRNA technique. Blast analysis revealed that sequence of the strain GO3 from goat milk identified as Lactobacillus casei, exhibited antibiotic sensitivity, auto-aggregation, co-aggregation, and antibiofilm assays highlighted inhibitory properties as a promising therapeutic potential probiotic bacterium. LAB isolates can be further investigated at the genetic level to enhance their probiotic characteristics such as resistance and cellular adhesion. Additionally, the identification of gene responsible for expressing bacteriocins can be conducted on these isolates.

Screening of lactic acid bacteria with the ability to reduce goaty flavor related fatty acids in goat milk

In this study, we conducted sensory evaluation and gas chromatography–mass spectrometry analysis on fermented goat milk samples prepared by 12 strains of lactic acid bacteria (LAB) isolated from goat milk to screen for strains with the ability to reduce the goaty flavor. The bacterial counts of fermented goat milk was 7.07–9.01 log CFU/mL. The electronic nose distinguished fresh goat milk (FGM) and fermented goat milk, and the electronic tongue results showed that Leuconostoc citreum 1, 4, 20, 22, 32, and 57, Latilactobacillus curvatus 144 and 147 imparted fermented goat milk a taste different from FGM. Overall, Leuconostoc citreum 57, Leuconostoc citreum 126, Latilactobacillus curvatus 142, Latilactobacillus curvatus 143, and Latilactobacillus curvatus 147 were screened with the ability to improve the flavor of goat milk. They gave fermented goat milk a goat flavor score lower than or equal to FGM. And the fermented goat milk samples 57, 126, 142, 143, and 147 contained 25, 22, 15, 24, and 17 volatile flavor compounds, respectively, with a greater variety and content of ketones and aldehydes and lower levels of hexanoic acid, octanoic acid, and decanoic acid than FGM. However, the pH and WHC results indicated that the application of these strains as secondary cultures is necessary. Our finding provides basic research data to improve the flavor of goat milk products.

Analysis of milk adulteration by means of a potentiometric electronic tongue

The adulteration of milk presents significant challenges in the food industry, promoting the need for efficient detection methods. This study introduces a potentiometric electronic tongue for rapid and accurate milk adulteration detection. Utilizing polymeric membranes integrated with various additives, the electronic tongue distinguishes between different milk types and detects common adulterants. Experimental results demonstrate its effectiveness in discriminating raw, pasteurized, and medicated cow milk, as well as goat milk. Moreover, it successfully identifies adulterants like water and bovine milk in goat milk samples. Chemometric analyses, including Principal Component Analysis and Partial Least Squares regression, correlate sensor responses with traditional milk parameters such as fat, protein, and lactose content with up to a 0.97 R2 on the validation step. Strong correlations validate the electronic tongue's potential for rapid milk quality assessment. This innovative approach offers a cost-effective, reliable solution for detecting milk adulteration in contrast with current techniques that require numerous, time consuming experiments.

Effect of Milk Sources on Whey Protein and Fractions of Casein

Aim: Milk from Cow, Buffalo and goat was used for the study of isolation and fractionation of casein and whey proteins. Buffalo and goat milk were subjected to physicochemical attribute studies and a detailed protein profile namely total protein, casein fractions α-, β- and κ casein and whey protein were separated by urea fractionation method. The aim of this study was to compare various casein fractions isolated from cows, Buffalo and Goat milk. The method of separating casein into its fractions is based on the solubility of the individual components in urea the solution. The separation of casein fractions was carried out in dissolving molar concentration of urea and the yield of fractions and total protein percentages were calculated. Buffalo and goat milk have comparatively higher total protein and whey protein content as compared to cow milk. Maximum whey proteins found in goat milk (20.58%) whereas cow milk had the lowest whey protein (19.29%). Among casein fractions, α fraction (16.64%) was found maximum in Buffalo milk followed by cow (14.92%) and goat milk (5.42%). The goat milk showed the highest level of β casein (17.81%) whereas, the lowest concentration of β casein was found in cow milk (9.38%). Study Design: A significant contribution to the total milk production of India comes from buffalo milk and goat milk. Despite that, Buffalo milk and goat milk are not being utilized for many products because of difference in composition of different species milk and their inherent problems associated in the production of products. Place and Duration of Study: Karnataka Veterinary Animal and Fisheries Sciences University (KVAFSU), Dairy Science College, Hebbal, Bangalore Karnataka, India Materials: The Goat milk samples were collected from Sinchana Goat and Sheep farm, Marenahalli village (Bengaluru Rural Dist) and Buffalo milk was obtained from Country Delight Pvt. Ltd., J. P. Nagar, Bengaluru, Karnataka. Cow milk used in this investigation was collected from SEDP, Dairy Science College, Hebbal, Bengalore.. All the glassware used was soaked in chromic acid solution, repeatedly washed with water, rinsed with distilled water and dried before use. For microbiological analysis dried test tubes, conical flasks, pipettes were cotton plugged and sterilized in a hot air oven. The chemicals and reagents used in this study were mainly of analytical grade procured from Prince Laboratory Company Pvt. Limited, Bangalore. The protein molecular weight markers used for the electrophoretic study were procured from Bangalore Genei Pvt. Ltd. Methodology: Standard urea fractionation method adopted by Hipp et al was used for isolation and fractionation of caseins. Skim milk was prepared by subjecting whole milk for centrifugation, the skim milk obtained was acidified using 1 % hydrochloric acid at 200 C to obtain casein precipitate. Obtained whole casein was dissolved in 3.3 M urea at pH 7.5 and adjusted to pH 4.6 which precipitates the bulk of α casein and leaving k-caseins into soluble filtrates. Again the supernatant was adjusted to pH 4.9 diluted to 1.0 M urea and warmed to 300 C precipitating the β-caeisn. Further, addition of ammonium sulphate was used to isolate k-casein from the precipitate. Results: The sources of protein had a significant influence on the total casein, casein fractions and whey protein content of different species. The highest quantity of total caseins (34.30g/l) and whey protein (8.87 g/l) were observed in buffalo milk followed by cow (28.52 g/l) and lowest was observed in goat milk (28.45 g/l). Total protein, casein and whey protein contents were greatly affected by the source of milk. Conclusion: The significant effect of source of milk on total protein, casein, its fractions and their yield was observed. highest yield of casein (54.31%) was observed in cow milk than buffalo milk (48.95 %) and lower yield was found in goat milk. Amongst the three species, highest per cent of β casein was noted in goat milk (54.05 %) followed by buffalo (36.03%) and cow milk (34.14%). Recommendation: Rasagulla will be consumed universally by all age groups globally. Thus, the consumption of Rasagulla helps in providing overall nutritional requirements. However, the study has been conducted on a pilot scale. Moreover, commercial production may necessitate huge cost on enzymatic modification of proteins and separation peptides for value addition.

Novel and Sensitive Touchdown Polymerase Chain Reaction Assays for the Detection of Goat and Sheep Milk Adulteration with Cow Milk.

Milk is the most consumed liquid food in the world due to its high nutritional value and relatively low cost, characteristics that make it vulnerable to adulteration. One of the most common types of milk adulteration involves the undeclared addition of cow's milk to milk from other mammalian species, such as goats, sheep, buffalo or donkeys. The incidence of such adulteration not only causes a crisis in terms of commercial market and consumer uncertainty but also poses a risk to public health, as allergies can be triggered by proteins in undeclared cow's milk. In this study, a specific qualitative touchdown (TD) PCR method was developed to detect the undeclared addition of cow's milk in goat and sheep milk based on the discrimination of the peak areas of the melting curves after the modification of bovine-specific primers. The developed methodology has high specificity for the DNA templates of other species, such as buffalos and donkeys, and is able to identify the presence of cow's milk down to 1%. Repeatability was tested at low bovine concentrations of 5% and 1% and resulted in %RSD values of 1.53-2.04 for the goat-cow assay and 2.49-7.16 for the sheep-cow assay, respectively. The application of this method to commercial goat milk samples indicated a high percentage of noncompliance in terms of labeling (50%), while a comparison of the results to rapid immunochromatographic and ELISA kits validated the excellent sensitivity and applicability of the proposed PCR methodology that was able to trace more adulterated samples. The developed assays offer the advantage of multiple detection in a single run, resulting in a cost- and time-efficient method. Future studies will focus on the applicability of these assays in dairy products such as cheese and yogurt.

Enzymatic Modification of Cow, Buffalo and Goat Milk Proteins and their Effect on Anti-Oxidant Activity and Digestibility

Aim: Buffalo milk and goat milk were enzymatically hydrolyzed to have 5, 10 and 15 per cent DH to improve the techno-functional properties of milk proteins in order to utilize in production of channa based dairy products. Study Design: A significant contribution to total milk production of India comes from buffalo milk and followed by cow and goat milk. Inspite of that, Buffalo milk and goat milk are not being utilized for many products in view of their inherent problems associated in production of Chhana based dairy products. Buffalo milk and goat milk were enzymatically hydrolyzed to have 5, 10 and 15 per cent DH to improve the techno-functional properties of milk proteins in order to utilize in production of products. Place and Duration of Study: Karnataka Veterinary Animal and Fisheries Sciences University (KVAFSU), Dairy Science College, Hebbal, Bangalore Karnataka, India Methodology: The Goat milk samples were collected from Sinchana Goat and sheep farm, Marenahalli village (Bengaluru Rural Dist) and Buffalo milk was obtained from country Delight Pvt. Ltd., J. P. Nagar, Bengaluru, Karnataka. Cow milk used in this investigation was collected from SEDP, Dairy Science College, Hebbal, Bangalore. Commercially available pure Neutrase enzyme was purchased from DSM Nutritional Products India Pvt. Ltd, Bangalore. All the glassware used were soaked in chromic acid solution, repeatedly washed with water, rinsed with distilled water and dried before use. For microbiological analysis dried test tubes, conical flask, pipettes were cotton plugged and sterilized in hot air oven. The chemicals and reagents used in this study were mainly of analytical grade procured from Prince Laboratory Company Pvt limited, Bangalore. The protein molecular weight markers were used for the electrophoretic study were procured from Bangalore Genei Pvt Ltd. Results: Highest protein content was noted in buffalo casein hydrolysate (83.0 %) than cow (81.0 %) and goat (81.16 %) and lowest nitrogen and ash content was observed in goat casein hydrolysate (13.65 %) and (15.20 %) respectively. (Akshya pl include few lines of enzymatic modification on anti-oxidant property and digestibility copy from discussions) Conclusion: Though buffalo milk contributes nearly half of the total milk production of India and goat milk carries both nutritional and therapeutic benefits, the potential utilization of both these milks are very much limited due to the inherent problems associated with them. This investigation has shown that by enzymatically hydrolyzing buffalo milk and goat milk to 5 per cent DH results significant improvement in physico-chemical and functional attributes Rasagulla which is on par with cow’s milk protein hydrolysates. Recommendation: Scavenging activity or anti-oxidant activity and Digestibility of hydrolysates has been studied as influenced by the extent of enzymatic modification in this study.

Highly selective and sensitive immunoassays for flurogestone acetate analysis in goat milk: From rational hapten design and antibody production to assay development

The preparation of high specificity and affinity antibodies is challenging due to limited information on characteristic groups of haptens in traditional design strategy. In this study, we first predicted characteristic groups of flurogestone acetate (FGA) using quantitative analysis of molecular surface combined with atomic charge distribution. Subsequently, FGA haptens were rationally designed to expose these identified characteristic groups fully. As a result, seven monoclonal antibodies were obtained with satisfactory performance, exhibiting IC50 values from 0.17 to 0.45 μg/L and negligible cross-reactivities below 1% to other 18 hormones. The antibody recognition mechanism further confirmed hydrogen bonds and hydrophobic interactions involving predicted FGA characteristic groups and specific amino acids in the antibodies contributed to their high specificity and affinity. Finally, one selective and sensitive ic-ELISA was developed for FGA determination with a detection limit as low as 0.12 μg/L, providing an efficient tool for timely monitoring of FGA in goat milk samples.

Prevalence and antimicrobial resistance profiles of mastitis causing bacteria isolated from dairy goats in Mukurweini Sub-County, Nyeri County, Kenya.

Ruminant mastitis continues to be a cause of economic losses in the dairy industry and remains a major public health hazard globally. This cross-sectional study was carried out in Mukurweini Sub-County of Nyeri County, Kenya, to investigate the prevalence of bacteria causing mastitis, risk factors associated with goat mastitis and the antibiotic resistance profiles of bacteria isolated from the goat milk. Farm level data on risk factors for mastitis was obtained from 56 farmers using a semi structured questionnaire. A total of 189 goat milk samples were collected. The goat's udder was observed for signs of clinical mastitis and the California Mastitis Test (CMT) used to test the milk for sub-clinical mastitis. All samples were then cultured for morphological identification of bacteria and strain typing by Matrix Assisted Laser Desorption/Ionization (MALDI)-Time of Flight (ToF) technique. Antimicrobial susceptibility of the isolated Staphylococcus aureus, coagulase-negative Staphylococcus (CoNS), Escherichia coli, Klebsiella oxytoca, Pseudomonas spp., Enterobacter spp., Proteus vulgaris and Escherichia vulneris to eight commonly used antibiotics was done by the disc diffusion method and validated by determining the presence of antibiotic resistance genes (mecA and blaTEM) using polymerase chain reaction method. The prevalence of clinical mastitis was 1.1% (2/189) while that of sub-clinical mastitis was 84.7% (160/189). Higher (p<0.05) prevalence of mastitis was observed in goats whose houses were cleaned fortnightly and in cases where farmers used same towel to dry different does' udders during the milking process. Thirteen different bacterial species were isolated from the milk samples and identified by MALDI-ToF, and these included S. aureus (22.0%), CoNS (20.3%), E. coli (18.1%), Pseudomonas spp. (14.3%), Enterobacter spp. (10.4%), K. oxytoca (6.0%), E. vulneris (1.7%), P. vulgaris (1.7%), Raoutella ornithinolytica (1.7%), Stenotrophomonas maltophilia (1.1%), Pantoea agglomerans (1.1%), Serratia marcescens (1.1%) and Cedeceas spp. (0.6%). One hundred pathogenic bacterial isolates were randomly selected and tested for antibiotic sensitivity to eight antibiotics out of which S. aureus were 97.5% resistant to Oxacillin and 100% sensitive to Ciprofloxacin. The CoNSs were 100% resistant to Oxacillin and 100% sensitive to Ciprofloxacin. E. coli were 93.9% resistant to Oxacillin, 69.7% sensitive to Ciprofloxacin and 87.9% sensitive to both Amoxicillin/Clavulanic acid and Meropenem. The antimicrobial resistant genes detected in S. aureus and E. coli were mecA [66.7%, 0%], and blaTEM [20% and 78.3%], respectively. In conclusion, the study showed that most of the does were affected by subclinical mastitis with the main causative bacteria being Staphylococci spp. and coliforms. Farmers need to be trained on improved control of mastitis by adoption of good milking practices and use of CMT kit for early detection of mastitis. Occurrence of multidrug resistance by key mastitis causing pathogens was shown to be prevalent and therefore there is need for development of intervention strategies.

Qualitative characteristics of sheep's and goat's milk in Albania.

Cost-effective methods are crucial in small-scale operations to assess the physicochemical properties of milk, identify potential clinical or subclinical mastitis, and test β-lactams in small ruminants. The aim was to evaluate the importance of physicochemical characteristics, somatic cells, and antibacterial substances as factors for monitoring the quality and safety of bulk tank milk from sheep and goats. Furthermore, we aimed to elucidate the influence of grazing capacity on the composition of sheep milk. The fat content of sheep milk (n=119) was found to be 7.7%, with a range of 5.3% to 9.9%. The average fat content of dairy goats (n=33) was found to be 4.9%, with a range of 2.8-6.7%. The results indicate that 2.8% of sheep milk samples and 7.8% of goat milk samples exhibited clear positive reactions when assessed using the California mastitis test. β-lactam antibiotics were present in 0.7% of sheep milk samples, but not in any of the goat milk samples using lateral flow strips. This measurement method can be useful to detect adulterated milk and better understand the quality and safety of small ruminant milk before processing.

Unveiling the culturable bacterial diversity, pathogens and impact of seasonality on microflora of raw goat milk: A phylogenetic outlook

Goat milk can be beneficial in cardiac diseases, mouth ulcers, dengue fever, etc. but ingestion of raw goat milk may have severe side effects as it may comprise pathogenic bacteria. Raw goat milk samples (n-55) were collected from diverse villages of the Udaipur district, Rajasthan, India and analyzed for bacterial diversity and pathogens using biochemical, molecular, and bioinformatic methods. Goat milk samples displayed an incidence of 36.36% for bacterial pathogens and the most prevalent bacteria reported were Listeria spp. and Staphylococcus spp. Bacillus cereus and Staphylococcus xylosus showed high resistance to tested antibiotics followed by Listeria. The dominant phylum found in the raw goat milk was Firmicutes (67.47%) and the dominant genus was Bacillus (28.32%). Listeria sp. was found dominant during the winter season while Staphylococcus spp. was dominant during summer. Three novel species were identified viz. S. xylosus (GM61), Streptomyces sp. C7 (GM2) and Pantoea agglomerans (GM31) can be further explored for their potential applications as bacteriocin producers' which can be used as food preservatives. New antibiotics or any antimicrobial produced by these three novel species can be used for the treatment of diseases. Pseudomonas yangonensis and Streptomyces sp. have not been previously reported in goat milk at the global level while S. xylosus at the National level.

Solid phase extraction technology combined with UPLC-MS/MS: a method for detecting 20 β-lactamase antibiotics traces in goat's milk.

We develop and validate a method for the rapid determination and identification of 20 β-lactamase antibiotics traces in goat's milk by combining the solid phase extraction technology with ultra-high performance liquid chromatography-tandem mass spectrometry. Goat milk samples were extracted with acetonitrile twice. The supernatant was then extracted and cleaned by solid-phase extraction using divinylbenzene and N-vinylpyrrolidone copolymer. The method was validated, with limits of quantification (LOQs) of 0.3 μg kg-1, specificities of 1/3 LOQ, linearities (R2) > 0.99, recoveries of 80-110%, repeatabilities <10.0%, and intermediate precisions <10.0%. The developed method was suitable for the routine analysis of β-lactamase antibiotics residues in goat's milk and was used to test 76 goat milk samples produced in China.

Detection of Maedi Visna Virus (MVV) in milk samples of Indian goats

Detection of Maedi Visna Virus (MVV) in milk samples of Indian goats

Prevalence and antimicrobial drug resistance of methicillin-resistant Staphylococcus aureus isolated from nasal swabs and milk samples of sheep and goats

Prevalence and antimicrobial drug resistance of methicillin-resistant Staphylococcus aureus isolated from nasal swabs and milk samples of sheep and goats

Experimental Protocol to Toxoplasma gondii Detection in Fresh Goat Milk.

Toxoplasma gondii is a zoonotic parasite with global distribution capable of infecting homeothermic animals. Transmission of protozoan to humans includes ingestion of water and raw food contaminated with sporulated oocysts, ingestion of raw or undercooked meat with tissue cysts, and tachyzoites' transplacental transmission. Fresh goat milk intake has already been linked to human toxoplasmosis outbreaks, but little is known about the infectious potential of this biological sample. Accordingly, the aim of the present study is to assess the survival and infectivity of T. gondii tachyzoites in fresh goat milk samples through an experimental protocol to detect this parasite via bioassay carried out with a murine model, DNA amplification, and serology. Swiss Webster mice were inoculated with fresh goat milk samples contaminated with different T. gondii RH strain tachyzoite concentrations per milliliter and stored for different refrigeration times. Animals showing clinical signs compatible to toxoplasmosis were euthanized. Milk samples contaminated with high parasitic loads and kept for a shorter refrigeration time were the most lethal ones. No significant differences were observed between mean death rates recorded for different goat milk contamination concentrations (p = 0.1888), and for the refrigeration time, contaminated milk samples were kept under (p = 0.9440). T. gondii DNA was amplified in all contaminated milk samples, but only one of the surviving mice was serologically positive. Results of the present study have shown T. gondii survival and infectivity in fresh goat milk samples, and it highlights its significant risk for public health. Therefore, molecular methods must be the tests of choice when milk samples are used to assess infection caused by protozoan in goats' dairy products.

Antibacterial and Anti Diabetic Activities of Ethyl Acetate Fractions of Lactobacillus Isolated from Cow and Goat Milk

ABSTRACT: Antibiotics are one of our most important weapons in fighting with bacterial infections and diabetics. Drugs were derived from natural sources that play an important role in the treatment and prevention of human diseases. Traditional fermented foods containing lactic acid bacteria such as milk, yogurt, curd, etc., have historically been consumed by human. Lactobacilli are well known friendly bacteria for their probiotic activities against pathogens. In this investigation cow and goat milk samples were selected and collected for the study. The gram stain was used for morphological identification of Lactobacillus sp. in the two samples. The two isolated Lactobacillus sp. from goat and cow milk samples were subjected to the extraction of secondary metabolites using the solvent ethyl acetate. The two extracts of Lactobacillus spp. those were isolated from cow and goat milk samples, showed antibacterial activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa. The zone of inhibition was assessed by mm. The good results of zones were observed at 1000 and 2000 µg in cow milk and 2000 µg in goat milk extraction. These metabolites were also showed good results in antidiabetic activity using the alpha amylase inhibition activity. The IC50 value has showed moderate activity in the two crude extractions when compared to acarbose standard drug. Therefore, in this investigation the Lactobacillus sp. producing secondary metabolites was good source for the activity of antibacterial and antidiabetic activity.

Protein Stability in Pasteurized Cow and Goat Milk using Protein Gel Electrophoresis

Milk is a nutritious beverage that contains whey, casein, and milk fat globule membrane (MFGM) proteins. Pasteurization kills pathogenic microorganisms in milk, making it safe to drink. A high heat load during processing can affect the protein quality of milk. In this study, protein gel electrophoresis (Native and SDS-PAGE) was used to view the protein profiles of retail cow and goat milk samples pasteurized at different temperatures (145, 165, or 280 °F) compared to commercially spray dried milk (356–482 °F). SDS-PAGE provided better resolution of the milk proteins compared to Native-PAGE. There were clear species differences in the MFGM proteins. This could be used to spot adulteration of goat milk with cow milk, however none of the samples showed signs of adulteration. There were no overt patterns of protein degradation with increasing pasteurization temperature. However drying reduced band intensity, especially MFGM and whey proteins in the goat milk sample. Whereas most samples came from different herds where genetics and environmental conditions varied, two of the goat milk samples were from the same herd, one fresh and one spray dried. It was evident from these two samples that spray drying can alter proteins in goat milk. Even so, if fresh milk is unavailable or unaffordable, dry milk remains a valuable protein source.