Cow Milk Samples Research Articles

Draft genome sequencing of multidrug-resistant Pseudomonas asiatica strains isolated from dairy cows with clinical mastitis and their farm environment.

We report, for the first time, the draft genomes of four multidrug-resistant Pseudomonas asiatica strains isolated from milk (2M1), feces (2F1 and 2F2), and farm soil (2S1) samples of dairy cows with clinical mastitis. The assembled genomes of these strains were 5.7 Mbp, 62.8% G + C content, and 50× genome coverage.

Prevalence of pathogens and antimicrobial resistance of isolated Staphylococcus spp. in bovine mastitis milk in South Korea, 2018-2022.

Staphylococcus spp. are one of the most predominant isolates in milk samples of dairy cows with mastitis worldwide. The aims of this study were to investigate the prevalence of bacterial pathogens in bovine mastitis milk samples in South Korea and the antimicrobial resistance profiles of staphylococcal isolates. In total, 1,245 strains were isolated from 1,260 mastitis quarter milk samples (with somatic cell counts ≥200,000 cells/mL) from 66 dairy farms between 2018 and 2022. The bacterial genus with the highest prevalence in bovine mastitis milk samples was Staphylococcus spp. (33.9%), followed by Streptococcus spp. (11.5%). S. aureus and non-aureus staphylococci (NAS) accounted for 11.0% and 89.0% of staphylococcal isolates, respectively. S. chromogenes was the most prevalent species among the 22 NAS species detected. S. aureus showed the highest resistance rates to penicillin (25.0%) and ampicillin (20.8%), whereas NAS showed the highest resistance rates to penicillin (18.3%), tetracycline (11.4%) and erythromycin (10.1%). Sixteen multidrug-resistant (MDR) isolates were only isolated from NAS, and the most commonly detected antimicrobial resistance gene in the 16 MDR isolates was mecA (75.0%), followed by tetK (62.5%), blaZ (50.0%), ermC (50.0%), and lnuA (43.8%). In conclusion, NAS were the most common isolates from mastitis milk in South Korea and MDR isolates carried a variety of antibiotic resistance genes. Our study suggests that continuous monitoring of the distribution and antimicrobial resistance in Staphylococcus spp., particularly NAS, is needed to improve the effectiveness of management and treatment strategies in dairy farms.

Effectiveness of pasteurization for the inactivation of H5N1 influenza virus in raw whole milk

Highly pathogenic avian influenza (HPAI) clade 2.3.4.4b H5Nx viruses continue to cause episodic incursions and have been detected in more than 12 taxonomic orders encompassing more than 80 avian species, terrestrial and marine mammals, including lactating dairy cows. HPAI H5N1 spillover to dairy cattle creates a new interface for human exposure and raises food safety concerns. The presence of H5N1 genetic material in one out of five retail pasteurized milk samples in the USA has prompted the evaluation of the pasteurization processes for the inactivation of influenza viruses. Our study examined whether pasteurization could effectively inactivate HPAI H5N1 spiked into raw whole milk. First, we heated 1 mL of non-homogenized cow milk samples to attain an internal temperature of 63°C or 72°C and spiked with 6.3 log10 EID50 of clade 2.3.4.4b H5N1 virus. Complete inactivation was achieved after incubation of the H5N1 spiked raw milk at 63°C for 30 min. In addition, viral inactivation was observed in seven of eight experimental replicates when treated at 72°C for 15s. In one of the replicates, a 4.44 log10 virus reduction was achieved, which is about 1 log higher than the average viral quantities detected in bulk milk in affected areas. Therefore, we conclude that pasteurization of milk is an effective strategy for mitigation of the risk of human exposure to milk contaminated with H5N1 virus.

Novel electrochemical sensor based on poly([Cu(H2O)2P2]I2)/GCE for the determination of trimethoprim in clinical samples and cow's milk samples

A Novel bioanalytical detector based on Poly(Diaquabis(1,10-phenanthroline copper (II) Iodide) (poly([Cu(H2O)2P2]I2)/GCE) has been fabricated by potentiodynamic polymerization of [Cu(H2O)2P2]I2. The synthesized complex and the fabricated electrodes showed a promising electrocatalytic behavior towards the electrooxidation of Trimethoprim (TPM). Based on the regression coefficient value of scan rate with peak current and square root of peak current, the oxidation of TMP at poly([Cu(H2O)2P2]I2)/GCE was dominated by diffusion. Under the optimized experimental conditions and square wave voltammetric parameters, the poly([Cu(H2O)2P2]I2)/GCE revealed very wide responses in the range of concentration of 500 nM–160 μM with a limit of detection of 3.91 nM and a Limit of quantification of 13.02 nM with the relative standard deviation below 1.75 %. The valuable applicability of the fabricated sensor for the determination of TMP in real samples, including cow's milk, blood serum, and human urine, was successfully investigated. The electroanalysis results from the spike recovery and interference study provided an excellent range of recovery with an error percent of below 3.0 % in the combination effect with the potential interferents. The sensor exhibited excellent reproducibility, sensitivity, long-term stability, high accuracy, and fast response. The developed bioanalytical sensor revealed the best application prospect for biomedicine and environmental monitoring activities.

Molecular detection and phylogeny analysis of Coxiella burnetii detected from cattle and buffalo milk based on plasmid cbhE gene in West Azerbaijan of Iran

Humans and animals may get Q fever, which is caused by the Gram-negative coccobacillus Coxiella burnetii. The symptoms of Q fever may include a self-limiting febrile illness, pneumonia, endocarditis, or hepatitis. Infections are classified as either acute or persistent. Cattle, sheep, and goats are the most prevalent reservoir animals for this zoonosis. This research was conducted to identify C. burnetii using transposable and isocitrate dehydrogenase genes (IS1111, icd) and QpH1 plasmids. A total of 142 samples of raw buffalo and cow milk were collected from various locations within the West Azerbaijan region (see map). We used "nested" PCR techniques using primers based on the IS1111 and icd genes of C. burnetii, as well as conserved and variable portions of plasmid sequences, to identify C. burnetii and their plasmids in milk samples from buffalo and calves. Out of 142 milk samples that were positive for the chromosomal transposable genes (IS1111 and icd) at a rate of 16.9 percent (95 percent CI: 14.5 percent to 19.6 percent) and 7.1% (95 percent CI: 5.59 percent to 9.08 percent), respectively, 86 samples were positive for the QpH1 plasmid at a rate of 60.5 percent (95 percent CI: 52.35 percent to 68.2 percent). Based on a phylogenetic study of the icd and QpH1 genes, the majority of the isolates had a similarity of 99.45 to 99.9 percent. Conclusion: It was determined that the buffalo population in West Azerbaijan province represents a significant epidemiological factor with respect to Q fever and consequently public health.

Exposure to Aflatoxins and Ochratoxin A From the Consumption of Selected Staples and Fresh Cow Milk in the Wet and Dry Seasons in Ghana.

Across sub-Saharan Africa, the heavy reliance on mycotoxin-susceptible staple foods means that populations in the region are particularly vulnerable to chronic mycotoxin exposure. This study assessed the exposure risk to ochratoxin A (OTA) and aflatoxins (AFs) from 18 samples of selected staple foods (maize, millet, groundnut) and 56 fresh cow milk samples collected from across Ghana. The foods were sampled simultaneously to maximise comparability, and at two timepoints in March/April (during the dry season) and July/August (during the rainy season) to assess the effects of duration of storage and seasonal conditions on the mycotoxin levels as measured by high-performance liquid chromatography. The margin of exposure (MOE) approach was used to assess the exposure risk from consumption of the sampled foods. Each of the sampled staples was contaminated with OTA (0.19-3.11 ng/g) and at least one AF (0.75-13.05 ng/g B1, ND-12.12 ng/g B2, 0.1-9.95 ng/g G1, ND-16.78 ng/g G2). Up to 67% had contamination above European Food Safety Authority (EFSA) maximum limits, and 50% were above Ghana Standards Authority (GSA) limits. The fresh cow milk samples were contaminated with AFM1 in the range of 0.05-1.49 ng/g, with 95% above EFSA limits and 36% above GSA limits. Aflatoxin contamination in the staples was high, particularly in July/August when the wet conditions may have adversely impacted the handling and storage of farm produce. Variation in AFM1 between the two sampling periods mirrored total aflatoxin in the staples, suggesting that even if dairy cattle were grazing in open pasture and not being rationed on stored feed, then there was a high environmental presence of aflatoxigenic fungi. The MOE estimates were ≤ 533.09, far below the safe cut-off of 10,000 for suspected carcinogenic compounds. The high mycotoxin levels indicate a priority risk to child nutrition which relies heavily on cereal mixes based on one or all the three sampled staples. The data from this study underscore the urgent need for interventions to better appreciate and address mycotoxin exposure for enhanced food security and public health in Ghana and across sub-Saharan Africa.

Supplementation of isoacids to lactating dairy cows fed low or high forage diets: Effects on performance, digestibility, and milk fatty acid profile

Our objective was to determine the effects of isoacids (ISO) on the lactation performance, digestibility, and milk fatty acid (FA) profile of Holstein cows fed 2 forage NDF levels (FL). The study was 10-wk long (including 2-wk for covariate) utilizing a randomized complete block design. Sixty-four mid-lactating Holstein cows [662 ± 71 kg BW, 119 ± 51 DIM, 2 ± 0.9 parity] were blocked by parity, DIM, and prior milk yield (MY) for multiparous cows or genetic merit for primiparous cows, and randomly assigned to 1 of the 4 diets (n = 16). Diets were arranged as a 2 × 2 factorial, with 2 FL containing 21 (HF) and 17% forage NDF (LF) without (WIA) or with ISO supplementation (IA, 7.85 mmol/kg DM and 3.44 mmol/kg DM for isobutyrate and 2-methylbutyrate, respectively). Diets were balanced for similar NEL (1.58 Mcal/kg DM), CP (16.0%) and total NDF (27.2%). Feed intake and MY were recorded daily. Nutrient digestibility for each cow was determined using indigestible NDF as a marker, and fecal samples were collected at 8-time points (4 h intervals between samples). Individual cow milk samples composited over a 10-wk period were analyzed using gas chromatography for FA profile. The statistical model included FL, ISO, and FL × ISO as fixed effects and block as a random effect (lme4 in R). The ISO did not affect DMI (P = 0.13), while LF had greater DMI than HF diets (27.8 vs. 26.0 kg/d; P < 0.01). However, ISO increased MY (34.7 vs. 37.2 kg/d; P < 0.01) and ECM (41.9 vs. 39.0 kg/d; P < 0.01) by 7% in HF but not in the LF diet, suggesting FL × ISO interaction (P = 0.04). Interestingly, ISO increased ADG (0.4 kg/d) but decreased MUN by 9% only in LF diet as indicated by FL × ISO interaction (P < 0.01). Additionally, ISO increased DM, OM, NDF, and CP digestibility by 10-24% in HF (P < 0.01), but not in LF (FL × ISO; P > 0.05). As expected, ISO increased milk odd chain FA profiles in the IA groups irrespective of FL, e.g., the IA had greater C15:0 (1.87 vs. 1.54 g/100g FA; P = 0.03) and a tendency to be greater C17:0 levels (0.86 vs. 0.76 g/100g FA; P = 0.05) compared with WIA groups. Overall, ISO improved MY and nutrient digestibility in the HF whereas it increased ADG and decreased MUN in LF diet. Additionally, ISO increased milk odd chain FA (C15:0 and C17:0) regardless of FL.

Influence of different genotype combinations of β-lactoglobulin and β-casein in cow milk on physicochemical and sensory properties of stirred yoghurt

In this study, stirred yoghurts were produced from Turkish Holstein cow milk with different genotype combinations of β-lactoglobulin and β-casein. The distribution of AA, AB, and BB genotypes of β-lactoglobulin and A1A1, A1A2, and A2A2 genotypes of β-casein was determined in a total of 135 cow milk samples. Raw cow milk samples containing AA genotype of β-LG exhibited higher non-fat total solids, protein, and fat contents in comparison to milk containing AB and BB genotypes of β-LG. Compared to the samples made from milk with other β-LG genotypes, the stirred yoghurt made from milk with β-LG AA genotype showed lower degree of syneresis and higher for hardness, apparent viscosity, and consistency coefficient. The lowest number of grains, the perimeter of grains, and the visual roughness values were obtained in the stirred yoghurts made from milk with BB genotype of β-LG and A2A2 genotype of β-CN. The sensory analysis revealed that β-CN genotypes of milk significantly influenced the overall acceptability scores of the stirred yoghurts, while β-LG genotypes did not significantly influence these scores except for the visual grainy score. The findings of this study showed that the selection of specific milk protein genotypes resulted in substantial differences in the physicochemical and sensory properties of stirred yoghurt.

Prussian-Blue-Nanozyme-Enhanced Simultaneous Immunochromatographic Control of Two Relevant Bacterial Pathogens in Milk

Salmonella typhimurium and Listeria monocytogenes are relevant foodborne bacterial pathogens which may cause serious intoxications and infectious diseases in humans. In this study, a sensitive immunochromatographic analysis (ICA) for the simultaneous detection of these two pathogens was developed. For this, test strips containing two test zones with specific monoclonal antibodies (MAb) against lipopolysaccharides of S. typhimurium and L. monocytogenes and one control zone with secondary antibodies were designed, and the double-assay conditions were optimized to ensure high analytical parameters. Prussian blue nanoparticles (PBNPs) were used as nanozyme labels and were conjugated with specific MAbs to perform a sandwich format of the ICA. Peroxidase-mimic properties of PBNPs allowed for the catalytic amplification of the colorimetric signal on test strips, enhancing the assay sensitivity. The limits of detection (LODs) of Salmonella and Listeria cells were 2 × 102 and 7 × 103 cells/mL, respectively. LODs were 100-fold less than those achieved due to the ICA based on the traditional gold label. The developed double ICA was approbated for the detection of bacteria in cow milk samples, which were processed by simple dilution by buffer before the assay. For S. typhimurium and L. monocytogenes, the recoveries from milk were 86.3 ± 9.8 and 118.2 ± 10.5% and correlated well with those estimated by the enzyme-linked immunosorbent assay as a reference method. The proposed approach was characterized by high specificity: no cross-reactivity with other bacteria strains was observed. The assay satisfies the requirements for rapid tests: a full cycle from sample acquisition to result assessment in less than half an hour. The developed ICA has a high application potential for the multiplex detection of other foodborne pathogens.

Analysis of Inflammatory and Regulatory Cytokines in the Milk of Dairy Cows with Mastitis: A Comparative Study with Healthy Animals

ABSTRACT Bovine mastitis remains a major problem in the global dairy cattle industry. The acute invasion of udder by pathogens induces innate immune response as the first defence mechanism in subclinical and clinical mastitis. The aim of the study was to determine inflammatory and regulatory cytokines IL-2, IL-4, TGF-β1, IL-17A, beta-defensin 3 and IL-10 and their potential changes in milk of dairy cows with subclinical and clinical mastitis, and to compare the findings with healthy animals. Milk samples from 15 holstein Friesian breed cows were used in the study. Cows were divided into three groups based on their health status (5 healthy, 5 subclinical and 5 clinical animals). All samples were tested using immunohistochemistry to evaluate IL-2, IL-4, IL-10, IL17A, TGF-β1 and β-Def 3 proteins. Expression of all proteins was detected in all milk samples. High expression of IL-2, IL-4, IL17A, TGF-β1 was detected in healthy cows’ milk and in milk of cows with subclinical and clinical mastitis. However, expression of IL-10 and β-Def 3 in milk samples of healthy cows was significantly higher compared to the milk of cows with subclinical and clinical mastitis (p < .001). IL-10 and β-Def 3 can be considered as informative biomarkers in diagnosis of subclinical and clinical mastitis.

Determination of antibacterial and anti-biofilm activities of Terpinen-4-ol loaded polydopamine nanoparticles against Staphylococcus aureus isolates from cows with subclinical mastitis.

Mastitis in cows is one of the most important diseases that give rise to economic losses in dairy farms. Increasing antimicrobial resistance in Staphylococcus aureus, one of the most common causes of mastitis, is a significant health problem. Due to the problems encountered in treating infections caused by resistant strains, developing alternative treatment methods, such as Nanomaterial systems and natural agents, are important. The essential oil of Melaleuca alternifolia is used as an antibacterial and the primary active component is terpinen-4-ol. This study aimed to investigate the antibacterial and anti-biofilm activity of terpinen-4-ol and terpinen-4-ol loaded polydopamine (T-PDA) nanoparticles against S. aureus isolates, which were resistant to at least one group of antibiotics isolated from milk samples of subclinical mastitis cows. The S. aureus strains were identified by biochemical tests and verified with the API Staph kit. The antibiotic susceptibility of the isolates was determined by the disc diffusion method. The broth microdilution method determined the antimicrobial activities of the terpinen-4-ol and T-PDA nanoparticles, and anti-biofilm activities were assessed using the modified crystal violet method. All of the isolates were resistant to benzylpenicillin and susceptible to trimethoprim/sulfamethoxazole. Multi-antibiotic resistance was detected in the 11 S. aureus isolates used in this study. For the terpinen-4-ol and T-PDA nanoparticles, MIC values were determined in the range of 0.125-0.5% (µL/mL) and 0.125-0.25% (µL/mL), respectively. None of the isolates formed biofilms. As a result, it was found that the antibacterial efficacy of the T- PDA nanoparticles was higher against nine of the S. aureus isolates than against the terpinen-4-ol.

Dispersive solid phase extraction of some sulfonamide antibiotics from milk combined with dispersive liquid-liquid microextraction

A covalent organic framework based dispersive solid phase extraction was developed for extraction of several antibiotics from raw cow's milk samples. For this purpose, first, the milk proteins were precipitated by zinc sulfate and after centrifugation, the analytes were extracted by the sorbent. Then, the analytes were desorbed by a proper eluent and were more concentrated by a microextraction procedure. The extractant was used for the analysis of the analytes by high-performance liquid chromatography-diode array detector. Based on the results, acceptable extraction recoveries (62–71 %) and sensitive limits of detection and quantification in the ranges of 0.11–0.19 and 0.37–0.63 ng mL−1, respectively, were obtained. The method can analyze the analytes in broad concentration range. The introduced approach was used in the analysis of fifteen raw cow's milk samples. The obtained data showed that all samples were free of the analytes. According to these results, the method can be considered an efficient procedure for extracting the analytes from raw milk samples.

Draft genome sequencing of Pediococcus acidilactici strains isolated from cow's milk: unlocking insights into functional traits and applications.

Pediococcus acidilactici is a potential probiotic bacteria isolated from diverse sources. However, strains isolated from milk, especially from raw milk of healthy cows, have not been thoroughly studied. Here, we report the draft genome sequence of P. acidilactici strains MBBL5 and MBBL7, isolated from milk samples of healthy cows.

Seasonal Prevalence of Major Mastitis Pathogens Isolated from Crossbred Cow Milk Samples in Sub-tropical India

The dairy industry suffers significant financial losses due to mastitis. In order to control and prevent mastitis, it is imperative to continuously monitor the bacteriology, prevalence, and incidence of major mastitis pathogens. Thus, the objective of this research was to find out how often mastitis causing bacteria were isolated from milk samples of crossbred cows over various seasons in India's sub-tropical environment. 240 milk samples from 80 different cows were collected over the course of three seasons [Hot Dry (April to June), Hot Humid (July to September), and Autumn (October to November)] in order to correlate the prevalence of four main mastitis pathogens (Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, and Escherichia coli) with the season. The most prevalent isolate during all seasons was Staphylococcus aureus. Our findings demonstrated a discernible relationship between seasonal change and the isolation rate of the bacterium associated with bovine mastitis, with the hot-humid season having the greatest pathogen isolation rate.

Isolasi dan karakterisasi bakteri asam laktat dari susu sapi di Indonesia

Cow's milk is a source of nutrition that has a good impact on health and contains a variety of microorganisms, one of which is lactic acid bacteria (LAB) such as Streptococcus thermophilus and Lactobacillus sp. Therefore, this study aimed to isolate and characterize LAB from the milk of Friesian Holstein dairy cows in Indonesia. In addition, BAL enumeration was carried out to determine the population of LAB in cow's milk samples. Based on the results obtained, as many as 4.36 log CFU/mL of LAB was successfully enumerated in the sample. Cell morphology observations showed that there were 15 Streptococcus, and 35 Lactobacillus candidate isolates which were Gram positive, did not form endospores, and did not have a wax coating on their cell walls. Furthermore, negative results of the catalase test were shown by 10 Streptococcus and 35 Lactobacillus candidate isolates. Carbohydrate fermentation test showed that isolate STRP1 and STRP4 were suspected to be Streptococcus sp., while the Lactobacillus isolates were possibly L. delbrueckii, L. acidophilus, and L. helveticus. The hemolytic test indicated that STRP1 is S. thermophilus with alpha hemolytic activity. Confirmation of the species of the isolates should be done through molecular identification and further characterization.

Friesian Holstein (FH) Dairy Cows Milk Quality that Experienced Repeated Breeding in Sendang District, Tulungagung Regency

This study observe the milk quality decrease in Friesian Holstein (FH) dairy cows that experience repeated breeding (repeat breedings) at KUD Tani Wilis Sendang Tulungagung when viewed from density, fat content, Total Solid (TS), and Solid Non Fat (SNF). The milk samples to be used in this study were 32 with a ratio of 10 normal cow's milk samples as a control. The milk sample was examined using a lactoscan. The data obtained were analyzed using the Independent T-Test test. The results of the repeat breeding cow's milk samples for specific gravity, fat content, and Total Solids (TS) showed a significant difference (p &lt;0.05) between the treatment group and the control of normal cow's milk. Samples of repeat breeding cow's milk on Solid Non Fat (SNF) showed that it was not significantly different (p&gt;0.05). The average specific gravity of repeat breeding cows was 1.0282 and that of normal cow's milk was 1.0260, which means that there is an increase in repeat breeding cow's milk when compared to normal cow's milk. The fat content of repeat breeding cows was 1.08% and that of normal cows was 4.18%. Total Solid (TS) of repeat breeding cows was 9.38% and normal cows was 12.73%.

Detection and characterization of Brucella species in rodents: A threat for the persistence of brucellosis in livestock farms

Brucellosis, caused by various Brucella species, poses a significant threat to global public health and livestock industries. This study aims to fill the knowledge gap concerning the presence of Brucella spp. in rodents on livestock farms in Iran. Both bacteriological and molecular surveys were conducted to assess the prevalence of Brucella spp. in these rodent populations. A total of 16 rodents were captured in four seropositive dairy cattle farms (n = 7) and two seropositive sheep farms (n = 9) and were then examined for the presence of the Brucella-infection. Five cow milk samples and 53 bovine lymph node samples from these farms were also tested for Brucella spp. Lymph node samples from dairy cattle farms contained 32 B. abortus biovar 3 isolates and one B. melitensis Rev1 vaccine isolate. The bacterial culture of rodents identified 12.5% of them (Mus musculus and Rattus norvegicus) harboring Brucella strains in dairy cattle farms. The rodents had B. abortus biovar 3 and B. melitensis biovar 1, suggesting a reservoir for these bacteria. A two-step molecular assay, utilizing the Omp28 sequences in tissue samples of rodents, demonstrated that 68.75% (n = 11) of the tested rodents yielded positive results. Bruce-ladder PCR and wboA typing on isolated bacteria revealed a close relationship to field strain of Brucella species. The study reveals that rodents on seropositive livestock farms in Iran harbor Brucella spp., indicating a potential reservoir for these bacteria. This highlights the importance of monitoring rodent populations through the molecular and bacterial methods to manage and control brucellosis in livestock.

Effect of selected bacteria of the genus Pseudomonas on the quality of raw cow’s milk

Pseudomonas spp. are a psychrotrophic species associated with milk spoilage caused by its enzymatic activities. The aim of this study was to identify Pseudomonas spp. in raw cow’s milk and to investigate their associated enzymatic properties and the ability to produce pyoverdine pigment. For microbiological analysis, 2 ml of milk samples was taken in sterile sample boxes. Milk sampling was carried out according to the principles of STN EN ISO 707. By identification using the PCR method, of n=320 samples of raw cow milk a total of 73 isolates of Pseudomonas spp. were identified as P. putida (34.25%); P. fragi (13.70%); P. lundensis (9.59%) and Pseudomonas spp. (42.47%). Proteolytic activity determined at a temperature of 7°C was positive from n=20 selected isolates of Pseudomonas spp. (60%) isolates and a temperature of 25°C was positively detected (85%). Lipolytic activity determined at a temperature of 7°C was confirmed in 35% of isolates and a temperature of 25°C it was confirmed in 70% isolates. Pyoverdine pigment production was detected in 65% of isolates. The results reveal the enzymatic activity of Pseudomonas spp. present in raw cow’s milk and its spoilage potential at different temperatures in relation to pigment production.

Mastitis challenges in Serbian dairy farming: a study on somatic cell counts and pathogen distribution

Mastitis is pressing concern for dairy herds due to its economic impact and potential health risks. Somatic cell counts (SCC), reflecting udder health, plays a crucial role in mastitis diagnosis. Current research explores the distribution of SCC and its correlation with various mastitis-causing pathogens in dairy farms in Serbia. The study analyzed 194 individual cow milk samples and microbiological testing was conducted under aseptic conditions to isolate and identify mastitis pathogens. The microscopic reference method was employed for assessing SCC in the milk samples. Among mastitis-associated isolates, bacteria were present in 28.87 %, yeast in 12.38 %, while in 5.15 % of milk samples, both bacteria and yeast were present. The relationship between SCC in various sample types (negative, bacteria-positive, yeast-positive, and samples with both bacteria and yeast) was noted. Importantly, samples with both bacteria and yeast presence had the highest SCC. While SCC is a valuable tool for monitoring udder health and the effectiveness of mastitis control programs, its response to specific pathogens is complex and doesn’t allow differentiation between pathogen types easily. This research highlights the challenges in distinguishing pathogen types based solely on SCC.

Occurrence and health risk assessment of mineral composition and aflatoxin M1 in cow milk samples from different areas of Sicily, Italy

This study aimed to determine 16 mineral elements (Cd, Pb, As, Na, Mg, Al, Ca, K, Cr, Mn, Fe, Ni, Cu, Zn and Se) using inductively coupled plasma mass spectrometry (ICP-MS) and a direct mercury analyzer (DMA-80) for Hg evaluation. Aflatoxin M1 was determined by high-performance liquid chromatography with fluorescence detection (HPLC-FLD) in cow milk samples. This research considered 180 milk samples, 20 by province (Palermo, Catania, Messina), collected for a period of three years (2020–2022) to assess the potential risks for consumer, the safety status and nutritional quality related to mineral intake by consuming of milk. All samples showed a Pb concentration below the limit reported by European Regulation 915/2023. Cadmium and Hg concentrations were below the Limit Of Quantification (LOQ) in all samples analyzed. The milk samples analyzed proved to be a good source of Ca (up to 44.5 % of the dietary reference values), with well percentages also for Na (up to 7.6 %), K (up to 23.1 %) and Mg (up to 11.1 %). Regarding trace elements, the results reported that chromium requires attention; its value was always higher than 168.8 % in all samples analyzed. Levels of arsenic and lead were up to 20.2 % and up 7.1 % respectively. Aflatoxin M1 concentrations were below the limit of detection (< 0,009 mcg/kg) in all milk analyzed. Therefore, further studies are needed to safeguard consumer health, the quality of the product and to assess the state of animal health.