Search Results (314)

The need for new feed ingredients that could reduce methane (CH₄) emissions from dairy cattle while maintaining rumen function is essential for sustainable milk production. This study aimed to evaluate the CH₄ mitigation potential of selected microalgae and macroalgae, along with an agro-industrial by-product, using two feeding strategies, and hypothesized that lipid- and polyphenol-rich materials would reduce CH₄ production in an inclusion-dependent manner. An in vitro batch culture study (24 h) was conducted to evaluate microalgae (Euglena gracilis and Aurantiochytrium spp.), macroalgae (Undaria pinnatifida), and an agro-industrial by-product (grape marc) either as feed additives (5%) or as a partial replacement of the concentrate mixture (30%, 50%, and 70%) in a basal diet consisting of 50% Klein grass hay and 50% concentrate mixture. As a feed additive, grape marc stands out for its potential to reduce CH₄ yield by about 43.3% without adversely affecting digestibility, pH, or total volatile fatty acid concentrations. When used as feed replacements, Euglena-, Aurantiochytrium-, and grape marc-based feeds reduced CH₄ yield at the highest replacement levels (50 and 70%); however, these effects were accompanied by decreased total gas production and volatile fatty acid concentrations, indicating reduced fermentation activity. Meanwhile, at a 30% replacement level, they showed promising efficiency as alternative feeds. Overall, CH₄ mitigation depends more strongly on inclusion strategy rather than feed type. Lipid-rich microalgae showed potential as concentrate replacements up to 30%, whereas grape marc was most effective as a feed additive for reducing CH₄ emissions. Full article

Rolled cheeses are a traditional specialty of the Vojvodina region in Serbia, produced through an artisanal process passed down across generations. This study evaluated the impact of the addition of selected herbs (a mixture of oregano and basil and chives added separately) on the microbiological, physicochemical, and sensory characteristics of rolled pasta filata cheese. Cheeses, both with and without herbs, were vacuum packed and stored at 4 °C for 60 days. The addition of oregano and basil significantly reduced aerobic mesophilic bacteria, Enterobacteriaceae, and Escherichia coli, while Salmonella spp. and Listeria monocytogenes remained undetectable throughout storage. Physicochemical analyses classified the cheeses as full-fat, semi-hard, with at least 45% milk fat in dry matter, and moisture in fat-free matter between 54% and 69%. All variants exhibited uniform shape, intact appearance, and a compact layered structure, while herbal-enriched cheeses developed a distinctive aroma and flavor. Sensory evaluation showed that all cheese types remained acceptable for up to 40 days, with minor deviations at day 60. Overall, the herbal addition enhanced sensory appeal, created new flavor profiles, and improved microbiological stability, demonstrating its potential as a natural strategy to extend the shelf life of traditional Serbian rolled pasta filata cheese. Full article

The combination of additives in ruminant diets is a growing strategy focused on cow health and productivity; therefore, the additives need to have synergistic effects when combined. Because of this, the objective of this study was to evaluate the effects of combining functional additives (biocholine, live yeasts, Yucca schidigera extract, and exogenous enzymes) on the productive performance, milk quality, rumen environment, oxidative status, and metabolic parameters of lactating Jersey cows maintained in an intensive system as well as verifying whether the effects on metabolism and the rumen environment (volatile fatty acids and microbiota) directly or indirectly influence productive efficiency. Eighteen Jersey cows in their second lactation were used, distributed in a completely randomized design into two groups: control, receiving a basal diet, and treatment, receiving the same diet plus the additive mixture. The experiment lasted 56 days. Dry matter intake, milk production and composition, feed efficiency, apparent digestibility, volatile fatty acid profile, rumen microbiota, hematological and biochemical parameters, and oxidative stress markers were evaluated. The combination of additives was able to increase milk production and production corrected for fat, protein, and energy, without altering dry matter intake, resulting in greater feed efficiency. There was an increase in milk protein content from day 28 onwards. In the rumen, a reduction in the protozoan population and an increase in the proportion of propionic acid were observed, without altering the ruminal pH or the total production of volatile fatty acids. The apparent digestibility of crude protein was higher in the treated group. The consumption of additives also promoted specific changes in the ruminal microbiota, with a greater abundance of microorganisms associated with carbohydrate degradation and less activity of pathways related to denitrification. From a systemic point of view, the treatment reduced markers of oxidative stress (reactive oxygen species—ROS and thiobarbituric acid reactive substances—TBARS), decreased creatine kinase and cholinesterase activity, and increased serum fructosamine concentration, indicating antioxidant, anti-inflammatory effects and improved energy status, respectively. It is concluded that the combination of plant biocholine, yeasts, Yucca schidigera extract, and exogenous enzymes improves productive efficiency, promotes ruminal fermentation, and contributes to greater metabolic and oxidative stability in lactating Jersey cows. Full article

Adulteration of milk powder (MP) is performed, especially in underdeveloped countries, by adding corn starch (CS) or wheat flour (WF) without mentioning it. Multiple techniques have been established to reduce these deceptive methods. Most of these techniques require samples to be sent to the laboratory for results through a time-consuming, expert-requiring, and destructive procedure. Raman spectroscopy (RS) has seen application due to the availability of portable modalities and its non-destructive, water-insensitive nature. Using principal component analysis (PCA), the differences and similarities between MP and the adulterants (CS and WF) have been evaluated. To quantify the percentages of CS and WF binary mixtures independently with MP, partial least squares regression (PLSR) has been employed. A total of 70 MP samples independently adulterated with CS and WF were prepared. Thirteen chemometric modes were developed by combining the first and second derivatives with Standard Normal Variate (SNV) and Multiplicative Scatter Correction (MSC) to quantify adulteration. The results obtained for CS and WF mixtures show errors of 0.76 and 0.77 %w/w, respectively, with the optimized math pretreatment. These results demonstrate that the portable RS modality can be used as an effective technique for detecting adulterants in milk powder. Full article

This study demonstrates the potential of Helicrisum plicatum (H. plicatum), Petroselinum crispum (P. crispum) and Origanum vulgare (O. vulgare) essential oils and their combination against four strains of two bacterial species, Listeria monocytogenes (L. monocytogenes) and Escherichia coli (E. coli), isolated from milk. GC/MS and GC/FID analyses of H. plicatum essential oil revealed α-pinene (27.61%), γ-curcumene (20.7%) and neryl acetate (5.88%) as the main compounds present in H plicatum essential oil. The main components of the essential oil of P. crispum were α-pinene (17.34%), 1,3,8-p-menthatriene (23.66%), β-phellandrene (10.41%) and myristicin (12.7%). In O. vulgare essential oil, carvacrol (58.3%), o-cymene (15.4%) and thymol (6.0%) were predominant compounds. Subsequently, an augmented simplex-centroid mixture design was applied to optimize the antibacterial efficacy of EO formulations against L. monocytogenes and E. coli. The simultaneous optimization all responses indicates that the optimal antimicrobial formulation was achieved using a ternary mixture of H. plicatum, P. crispum, and O. vulgare in a 16:16:68 (v/v/v) ratio. In parallel, an in silico study of four main essential oil components evaluated their drug-likeness, pharmacokinetic and toxicity properties, and binding to bacterial targets. These major compounds satisfy the main standards for drug-like molecules, with simulations pointing to good oral absorption, an acceptable safety profile, and stable binding to key enzymes in E. coli and L. monocytogenes, which supports their antibacterial potential. Overall, these combined experimental and computational results point to oregano, parsley, and immortelle essential oils as promising natural antimicrobial options for improving the preservation of dairy products. Full article

African swine fever (ASF), caused by the African swine fever virus (ASFV), is a highly contagious and fatal disease. Accurate detection in the early stages of an outbreak relies on molecular methods, but serological monitoring at the population level is also crucial for assessing the extent of exposure and past infections. This experiment developed an indirect enzyme-linked immunosorbent assay (ELISA) to detect antibodies against ASFV, using three ASFV RNA polymerase subunits (H359L, C147L, and D339L) as coating antigens. The recombinant proteins were successfully expressed in Escherichia coli and purified. Using a checkerboard titration method, we systematically optimized key assay parameters, determining the optimal coating conditions to be a mixture of H359L, C147L, and D339L at a volume ratio of 1:2:2, with individual concentrations of 1 μg/mL, 0.4 μg/mL, and 0.5 μg/mL, respectively. Other optimized parameters included a serum dilution of 1:200, a blocking buffer containing 5% skim milk, and specific incubation conditions for the secondary antibody and substrate. The cut-off value was established at 0.430 ($\overline{x}$ + 4SD) based on 30 negative sera. The established triple-antigen indirect ELISA exhibited high sensitivity (detecting positives at dilutions up to 1:3200) and excellent specificity (no cross-reactivity with antisera against CSFV, PRRSV, PRV, PCV2, and PEDV. Both intra and inter assay repeatability were confirmed, with coefficients of variation ranging from 1.020% to 7.600%. Validation with 123 clinical serum samples demonstrated a 96.75% concordance rate with a commercial kit. In conclusion, the three-antigen indirect ELISA established in this study exhibits high specificity and sensitivity, making it suitable for serological surveillance and exposure assessment of ASFV antibodies. It can be combined with molecular detection for epidemiological investigations and integrated prevention and control measures. Full article

Neonatal and weaning periods are the most challenging phases for enteric infections in dairy calves. While different approaches are used to minimize calf health issues, the neonatal diet remains the core approach to enhance pre- and post-weaning animal health and performance. This pilot study aimed to evaluate blood biomarkers of inflammation and fecal metabolites in calves supplemented with oligosaccharide mixture (OS) during the preweaning stage. Sixteen newborn Holstein dairy calves (eight females and eight males) were randomly assigned into two groups: control with no supplementation, or treatment with 50 g/day of OS added to the pasteurized waste milk feeding. Both control and OS-treated calves were fed pasteurized waste milk during the preweaning period and weaned at seven weeks of age. Blood and fecal samples were collected weekly. Fecal fatty acid metabolites were downregulated in treated calves compared to control calves (p ≤ 0.05). Markers of inflammation (i.e., haptoglobin) or liver response (i.e., albumin, paraoxonase) did not differ between groups (p > 0.05). Overall, these findings suggest that dietary intervention with oligosaccharides can affect host metabolic pathways. Full article

Background and Objectives: Milk with A2/A2 β-casein (A2 milk) is currently the subject of numerous studies on the effects of its consumption on health. Commonly consumed milk contains a mixture of β-casein of different genetic variants (most often A1 and A2). In the polypeptide chain of A2/A2 β-casein, proline occurs at position 67, while in β-casein A1/A2, histidine occurs. The main goal of the dietary intervention was to identify and compare the effects of consuming A2 milk, conventional milk (A1) and oat drink on bone health, cardiometabolic health and immune system function in adults. Methods: The controlled IMPA-CT (Investigating Milk and Plant Alternatives Comparative Trial) Study was a randomized study with three groups (A2 Milk group, A1 Milk group, and Oat Drink group). The study included 162 adults with normal and/or overweight, without coexisting chronic diseases, aged 30–60 years. The intervention study consisted of the consumption of 500 mL of an appropriate product (A2 milk/A1 milk/oat drink) daily for 12 weeks. After qualification of the subjects, before the start of the study (T1′), in the 4th week of the study (T2′), in the 8th week of the study (T3′) and at the end of the study, after 12 weeks (T4’), an assessment of the diet and nutritional status was planned. Body composition, bone mineral density (DEXA) and biochemical tests were done. The primary outcome will be the effect of cow’s milk variants and oat drink consumption on bone health. Secondary outcomes will include changes in nutrient intake and cardiometabolic health as well as the immune system in adults. Expected Results and Contributions: The study design, including extensive follow-up and robust endpoint measures, contributed to understanding the therapeutic potential and safety profile or otherwise of β-casein A2/A2 milk and plant-based drinks. Full article

Several solutions are being explored to reduce methane intensity in dairy farms, but there is no consensus for commercial pastoral dairy systems in temperate zones. We evaluated the effects of essential oils (EO) supplementation on CH₄ intensity and performance in dairy cows within a commercial pasture-based system in southern Chile. Thirty multiparous cows were randomly assigned to a control group and a treated group, with a general average yield of 22.3 ± 5.37 kg/d and an average parity of 3.42 ± 1.13. The treated group received concentrate supplemented with a mixture of EOs. Enteric CH₄ emissions were measured using GreenFeed^®. Milk yield (kg/d), composition (% fat, % protein, urea, somatic cells), plasma biochemistry, and grassland proximal analysis (NIRs) were also evaluated. Results showed a significant increase in fat-corrected milk production (4.6 kg) in the treated group during the first trial period where the grassland was highly nutritious, offering 19.8% crude protein as well as a pool of long-chain fatty acids. Additionally, CH₄ intensity was significantly lower in the treated group (1.3 gCH₄/ECM) during the first phase. EO supplementation strategies represent a suitable non-invasive intervention suitable for commercial grassland-based systems in southern Chile that is strongly influenced by pasture quality. Full article

Background and Objectives: Dairy products provide vital energy, high-quality protein, and micronutrients for over six billion people worldwide, with dairy cows contributing nearly 81% of global milk production. Sustainable strategies to enhance productivity are therefore critical. Feed additives such as essential oil blends (EOB), onion peel (OPE), and prebiotics including mannan oligosaccharides (MOS) and galacto-oligosaccharides (GOS) have been proposed to improve rumen fermentation, modulate microbial ecology, and mitigate greenhouse gas emissions. This study evaluated the combined effects of EOB, OPE, MOS, and GOS on rumen metabolism using the rumen simulation technique (RUSITEC). Materials and Methods: Rumen inoculum from three cannulated Holstein Friesian cows was incubated across 16 vessels (four treatments × four replicates) for nine days. Treatments included a control (CON; TMR only), GEO (TMR + GOS + EOB + OPE), MEO (TMR + MOS + EOB + OPE), and OLEO (TMR + a 1:1 mixture of GOS and MOS + EOB + OPE). Additives were included at 3 µL/g TMR for EOB and 30 mg/g TMR (3% w/w) for OPE, GOS, MOS, or OLG. Rumen effluents were collected for untargeted metabolomic profiling by liquid chromatography–mass spectrometry, identifying 661 metabolites. Results: Partial least squares-discriminant analysis revealed clear separation between CON and additive groups, confirming distinct metabolic shifts. GEO primarily enhanced tryptophan, tyrosine, and purine metabolism; MEO stimulated phosphonate and pyrimidine pathways and bile acid biosynthesis; OLEO promoted phosphonate, nicotinamide, and taurine metabolism. Microbial analysis showed enrichment of taxa such as Lachnospira, Succinivibrionaceae, Macellibacteroides, Lysinibacillus, and Christensenellaceae, indicating complementary effects on fermentation and microbial stability. Conclusions: These results demonstrate that dietary supplementation with GEO, MEO, or OLEO modulates rumen metabolism and microbial ecology without impairing fermentation, supporting improved nutrient utilization, antioxidant defenses, and metabolic resilience in dairy cows, with potential benefits for productivity and sustainability. Full article

A freeze-dried natural starter culture (NSC) was developed and assessed for its suitability in producing a semi-cooked, 60-day-ripened cheese resembling the protected designation of origin (PDO) Pecorino Sardo. The culture, derived from raw ewe’s milk from a dairy farm involved in the study, without thermal decontamination to preserve indigenous microbiota, was enriched with two strain-level-characterised, biodiverse mixtures of Streptococcus thermophilus (Str-mix) and Lactobacillus delbrueckii (Lb-mix). This study evaluated the technological robustness and adaptability of NSC enriched with biodiverse Str-mix and Lb-mix across three different artisanal dairy-processing environments with varying milk compositions and equipment levels at plants located in different geographic areas. During cheesemaking, technological, physico-chemical, and compositional parameters were monitored, along with microbial characterisation of milks and 1-day cheeses. After 60 days of ripening, cheeses were characterised from the microbiological, physico-chemical, and compositional perspectives. Furthermore, nutritional labelling was established, and consumer acceptance was determined. Results showed that the starter (NSC + Str-mix + Lb-mix) demonstrated strong and reproducible technological performance in all dairies, regardless of the milk’s chemical and microbial composition variability. Sensory quality was preserved in cheeses ripened for up to 180 days. These preliminary findings seem to support the use of freeze-dried, raw-milk-derived natural cultures in artisanal cheesemaking as a way to preserve microbial diversity and to reconnect with traditional practices that enhance both the tangible and intangible assets of modern society. Full article

Herein, we prepared nanoparticles of chitosan–manganese(II) complexes in different molar ratios (1:2, 1:1, and 2:1) and fully characterized them using dynamic and electrophoretic light scattering, X-ray diffraction, SEM, FTIR, and thermal analysis. Nanoparticles Chitosan + Mn²⁺ (1:1) have a high catalytic activity in the oxidative coupling of benzylamine, resulting in the imine formation and also in selective aldol reaction. Chitosan + Mn²⁺ (1:1) catalyze the reactions in the greenest solvents: water and water/ethanol mixture. Moreover, Chitosan + Mn²⁺ (1:1) is very easy to prepare and convenient to use. The catalyst is separated from the reaction mixture by a simple nanoporous filter or centrifugation and does not lose catalytic activity after at least ten uses. The chitosan–manganese(II) complexes reduce the milk fermentation time, demonstrating the effectiveness in accelerating the fermentation process by Streptococcus thermophilus. They also contribute to increasing the shelf life of fermented milk products by inhibiting the undesirable post-acidification process. We found that the optimal ratio of chitosan and Mn²⁺ to manifest the apogee of the desired effects (acceleration of milk fermentation and increase in the shelf life of the fermented product) is 1:2. Full article

Antibiotic stereoisomers as components of medicines are typically characterized by different biological activities. Because pharmaceuticals can include a racemic mixture of stereoisomers, monitoring of all forms is required. One contaminant of food products, antibiotic ofloxacin (OFL), as a chiral compound, has two enantiomers—the biologically active S-isomer and less active R-isomer. In this study, a sensitive immunochromatographic test system for simultaneous enantiospeсific detection of the two OFL isomers was developed for the first time. For this, polyclonal antibodies were produced, and conditions for a double lateral flow immunoassay (LFIA) were selected and optimized so that the cross-reactivity with another enantiomer was negligible. The LFIA was performed in a competitive format with gold nanoparticles as a label for secondary antibodies. The achieved LODs/cutoffs were 0.001/10 and 0.007/30 ng/mL for S-OFL and R-OFL detection, respectively; the assay procedure took only 15 min. A double LFIA was performed to detect S-OFL and R-OFL in milk with minimal sample pretreatment; the recoveries were 85–95%. The developed test system is an effective tool for the selective detection of both isomers of OFL, allowing for the avoidance of false negative results. This immunochromatographic approach can be promising for the control of other optically active food toxicants. Full article

The total antioxidant capacity (TAC) of food products is a key parameter for assessing food quality and safety. In this work, iron-doped carbon dots (Fe-CDs) were successfully prepared using waste coffee grounds as a precursor with a satisfactory fluorescence quantum yield of 9.6%. The Fe-CDs exhibited exceptional peroxidase-like activity, which can oxidize colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to form blue oxTMB. Concurrently, oxTMB induced an inner filter effect, quenching the fluorescence of Fe-CDs. After being added to antioxidants such as glutathione, ascorbic acid, and L-cysteine, the generated reactive oxygen species (ROS) are consumed, thereby preventing the oxidation of TMB. The color of the mixed solution changed from dark to light blue, accompanied by the fluorescence recovery of Fe-CDs. Nevertheless, these three antioxidants possessed remarkable differences in ROS elimination capability, which resulted in different signal responses in absorption and fluorescence, and were successfully used for constructing the colorimetric/fluorescent dual-channel sensor array. Furthermore, the sensor array signals were processed using principal component analysis to achieve simultaneous detection of glutathione, ascorbic acid, and L-cysteine, and were able to effectively discriminate between mixtures and individual antioxidants. The constructed sensor array was successfully applied for the TAC detection in various foods (including vegetables, fruit, and beverages) and for the precise differentiation of antioxidants in milk samples. Overall, the prepared sensor array exhibited outstanding potential in detecting food quality. Full article

Per- and polyfluoroalkyl substances (PFASs) are persistent and bioaccumulative contaminants frequently detected in animal-derived foods, raising concerns for consumer health. In 2020, the European Food Safety Authority (EFSA) established a group tolerable weekly intake (TWI) of 4.4 ng/kg bw per week for four PFAS (PFOA, PFNA, PFOS, PFHxS) based on immunotoxicity, prompting the European Commission to set maximum levels in food. However, many other PFAS are present in the diet, and their cumulative risk is poorly characterized. This study applied the Relative Potency Factor (RPF) approach, using hepatic toxicity as the reference endpoint. The RPF approach addresses a key challenge in assessing human dietary exposure to PFAS by enabling cumulative risk assessment for complex mixtures found in food, moving beyond single-compound evaluations. Occurrence data from EFSA’s 2020 opinion were combined with European consumption data for fish, meat, eggs, and milk across four population groups (toddlers, adolescents, adults, elderly). Exposure estimates, expressed in PFOA equivalents, were compared with the group TWI. Results showed toddlers as the most vulnerable, with cumulative exposure approaching or exceeding TWI through fish, meat, and eggs, while milk contributed less. PFOS and PFOA were the main contributors across all food categories, with PFNA and PFDA also relevant, especially in younger populations. The findings highlight the added value of the RPF approach for cumulative PFAS risk assessment and emphasize the need for updated monitoring, refinement of potency factors for under-studied PFAS, and continued regulatory measures to protect high-risk consumers. Full article