Lactotransferrin (LTF), a critical multifunctional glycoprotein, plays an essential role in the immune defence, growth and development, and milk quality of dairy cows. The regulatory mechanisms governing gene expression are intricate, with sequence variations in the promoter region potentially exerting a substantial impact on gene expression. In this study, sequencing analysis of the bovine lactotransferrin promoter region was conducted, leading to the identification of two linked single nucleotide polymorphism (SNP) sites. A significant association between these SNPs and lactotransferrin content was observed in a cohort of 301 Holstein cows. Subsequently, further investigation into the transcriptional activity of various lactotransferrin genotypes was performed by constructing promoter fragments encompassing different lactotransferrin genotypes. The findings reveal that the two SNPs significantly influence the activity of the lactotransferrin promoter, thereby affecting lactotransferrin expression. These results hold substantial implications for advancing our understanding of the regulatory mechanisms underlying lactotransferrin expression and for the genetic enhancement of dairy cows.

This research paper addresses the hypothesis that the in vivo criterion of bovine somatic cell count (SCC) < 200,000 cells/ml milk as a diagnostic marker for healthy mammary tissue is not suitable to be adopted to milk samples taken post slaughter. To study immune mechanisms associated with intramammary infections, we developed a mammary explant model. As SCC is routinely applied to differentiate between healthy and inflamed mammary tissue, donor cows were selected based on their milk SCC obtained in vivo. Furthermore, milk cell differentiation for early mastitis detection via flow cytometry allows identification of leucocyte subpopulations and complements SCC. To replace in vivo examination and allow for post mortem selection of donor cows, this explorative study aimed to investigate how slaughter influences the reliability of SCC and differential milk cell count (DMCC) and to assess their validity as diagnostic markers for udder health in bovine milk samples obtained post slaughter. Therefore, quarter milk samples from cows were obtained in vivo and post mortem and analysed to determine SCC and DMCC and identify major mastitis pathogens. The logarithmized numbers of SCC, non-viable cells, viable cells, lymphoid cells, polymorphonuclear (PMN) and large cells per ml milk were compared using linear mixed-effects models in milk samples obtained from cows in vivo and post mortem. The number of lymphoid cells, PMN and large cells was significantly higher in milk samples obtained post mortem than in vivo, with PMN being the most prominent cell population. Higher milk SCC values measured post mortem might be explained by migration of leucocytes into the periphery during slaughter. This should be considered when modelling intramammary infection in vitro using udder tissue. Reflecting these findings, it is not feasible to endorse SCC as a reliable marker for post mortem selection of donor cows with healthy mammary tissue for in vitro models.

This study tested the effects of the methylenetetrahydrofolate reductase (MTHFR) rs110692574 polymorphism and rumen-protected choline and methionine supplementation on biochemical parameters, milk yield, reproductive performance and health status during the transition period in Holstein cows raised in Türkiye. Genotypes of 356 cows were determined using the tetra-primer amplification refractory mutation system–polymerase chain reaction (ARMS-PCR) method. Following genotyping, 80 cows were selected and assigned to four groups based on nucleotide genotype at two loci (homozygous CC and heterozygous CT) and dietary supplement (choline or choline + methionine). Blood samples were collected on day 21 prepartum, on the day of parturition (day 0), and on day 21 postpartum to measure homocysteine, folic acid, vitamin B12, and non-esterified fatty acid concentrations. beta-hydroxybutyric acid (BHBA) values and production data were obtained from the farms’ routine monitoring records. Statistical analyses were performed using repeated-measures analysis of variance (ANOVA) to assess time-dependent effects, and a general linear model was used for between-group comparisons at the same time points. The frequency of the CT genotype was 12.64%. The polymorphism significantly affected folic acid and vitamin B12 concentrations across different stages of the transition period. Feed supplementation had a significant effect on folic acid concentrations on calving day and on day 21 postpartum, as well as on milk yield on days 100, 200 and 305. Moreover, the polymorphism was significantly associated with folic acid and vitamin B12 concentrations on day 21 prepartum and with BHBA values on day 7 postpartum. This variation was linked to specific health issues that could lead to decreased productivity. In conclusion, genotype-based nutritional strategies were found to play a key role in maintaining metabolic balance and enhancing productivity during the transition period.

The confirmatory factor analysis technique was used to quantify a latent variable for test-day lactation performance (TDLP) in the first parity of Chinese Holstein dairy cows by applying five measurable traits, including test-day milk yield (TDMY), test-day milk fat percentage (TDFP), test-day milk protein percentage (TDPP), test-day somatic cell score (TDSCS) and test-day milk urea nitrogen (TDMUN). The standardised factor loadings of TDMY, TDFP, TDPP, TDSCS, and TDMUN for describing TDLP were 0.46, −0.52, −0.70, −0.14 and −0.19, respectively. Genetic analysis was conducted using a multivariate repeatability model within a Bayesian framework. The posterior means for the heritability and repeatability estimates of TDLP were 0.26 ± 0.02 and 0.34 ± 0.02, respectively. In general, posterior means for heritability and repeatability estimates of the measurable traits were low to medium. The heritability estimates ranged from 0.05 for TDSCS to 0.28 for TDPP, and repeatability estimates ranged from 0.15 for TDMUN to 0.38 for TDMY. The latent variable of TDLP exhibited positive genetic (0.62) and phenotypic (0.40) correlations with TDMY, whereas its genetic and phenotypic correlations with other measurable traits were negative, ranging from −0.96 (TDLP–TDPP) to −0.11 (TDLP–TDSCS). The corresponding phenotypic correlations ranged from −0.85 (TDLP–TDPP) to −0.07 (TDLP–TDSCS). It may be concluded that breeding for higher TDLP might increase TDMY but could reduce milk composition traits. In general, the negative genetic and phenotypic correlations suggest a trade-off between milk quantity (yield) and quality (composition).

Plasminogen is an inactive protease in milk, which can be activated to plasmin. Whole milk contains fat and in response to lipase activity, free fatty acids are released. Free fatty acids are not known to act as an activator for plasminogen. The aim of this study was to determine whether commercial bovine plasminogen could be activated to plasmin by commercial free fatty acids present in milk, and also to determine if plasminogen activators to plasmin are present in abnormal milk using milk agar plates and the Merck protease assay. Fatty acids and activators present in abnormal milk had the ability to activate plasminogen to plasmin, which could, after weeks, harm milk protein stability during extended storage time (ultra-high temperature milk). The milk agar plate technique containing plasminogen could detect plasmin activators present in abnormal milk. This can act as an indicator of high-risk milk being used within the ultra-high temperature milk industry.

This Research Communication reports the physicochemical properties, aflatoxin levels and antibiotic residues in buffalo milk. The milk and feed samples were collected from nine farms in Peninsular Malaysia, with the lactation stage studied in one farm. Buffalo milk composition varied across farms; Petaling Jaya showed high fat and total solids but low protein and solids non-fat (SNF), while Jitra 1 and Seberang Perai 2 exhibited higher protein, casein and SNF. Langkawi and Hulu Langat had higher moisture, ash and lactose levels. Early and late lactation were linked to higher protein and casein. Aflatoxin B1 in feed was undetectable; however, aflatoxin M1, amoxicillin and oxytetracycline were present in milk but below the regulatory limits. These findings indicate that current on-farm management practices are effective in ensuring the safety and quality of buffalo milk, while continuous monitoring remains crucial.

This research paper investigated the hypothesis that the high production of 3-methylbutanal by lactic acid bacteria is achieved not only through a direct metabolic pathway but also via an indirect pathway. 3-methylbutanal is a flavour compound that contributes to the sensory profile of various cheeses, often described as nutty, malty, or chocolate-like depending on its concentration and the cheese matrix. Although it is desired in certain cheese varieties, its acceptability varies among different cheese types. Among the various compounds responsible for this nutty scent, 3-methylbutanal plays a pivotal role. Certain strains of lactic acid bacteria are known to produce 3-methylbutanal from leucine, via both direct and indirect pathways. While it has commonly been assumed that the direct pathway is the primary mechanism, this study reports the discovery of Lactococcus cremoris AJ01, which produces 3-methylbutanal predominantly through an indirect pathway. We first investigated the effects of milk fermentation conditions on 3-methylbutanal and acid production by strain AJ01. The effect of leucine supplementation on 3-methylbutanal production was then examined. Finally, we explored the metabolic pathway responsible for 3-methylbutanal synthesis in this strain, determined the nucleotide sequence of the pyruvate dehydrogenase gene involved in the indirect pathway, and evaluated its enzyme activity to assess its contribution to production. When cultured in milk at 20 °C, strain AJ01 produced titratable acidity at >0.6% and 3-methylbutanal at >6 mg/kg within 18 h. Adding leucine to the milk enhanced 3-methylbutanal production, while excessive leucine supplementation inhibited it. Strain AJ01 exhibited activity of pyruvate dehydrogenase, while no activity of α-keto acid decarboxylase, the direct-pathway enzyme, was detected, suggesting that it produces 3-methylbutanal via the indirect pathway. These findings may contribute to the effective management and enhancement of flavour profiles in fermented dairy products, particularly cheeses.

High-temperature short-time (HTST, 72°C, 15 s) pasteurization can be successfully used for human milk (HM) preservation. The purpose of this study was to compare the effects of different HTST heating methods: microwave (MHTST) and standard convective (CHTST) on macronutrients, fatty acids (FAs), lactoferrin (LF), vitamin C, lysozyme (LZ), α-amylase (α-A) activity, lipid oxidation and antioxidant properties of HM. Regardless of the heating methods, the macronutrients and FA content, LZ activity and antioxidant properties of HM proved to be insensitive to HTST treatment, while the concentration of vitamin C decreased by 42.6% and 50.2%, and the activity of α-A by 6.0 and 7.2% when using MHTST and CHTST, respectively. LF content changed significantly only when CHTST was used (42.3% reduction). There were no negative effects of microwave heating under controlled conditions on the HM components. Satisfactory results regarding the impact of MHTST on HM composition and potential economic benefits suggest that this technology can be applied in HM banks to ensure adequate safety and quality.

The aim of this study was to investigate whether hair can be used as a non-invasive sample material that is less influenced by homeostasis than blood. Blood analysis is an invasive method of assessing trace element status, concentrations can be influenced by homeostasis, and they might not accurately reflect the true status of the animal. Thus, hair samples could play an important non-invasive role in diagnosing chronic deficiencies. The study group included 100 veal calves of a variety of different breeds and crossbreeds aged between 2 and 5 months, consisting of both sexes. Samples were taken to compare different locations and colours of hair. The concentration of trace elements Mn, Fe, Se, Co, Cu, Zn and Mo of different coloured ear and shoulder hair (black, brown and white) were measured, and concentrations were compared with those in the liver, kidney, muscle and blood plasma. All samples were measured with triple-quadrupole collision/reaction cell ICP-MS. This study showed that both hair colour and hair location have an influence on trace element concentration. In this animal series, no strong correlations could be found between trace element concentrations in hair and other tissues, suggesting that such an approach is only feasible when a heterogeneous animal series is used. Whether hair is a feasible sample material for trace element analysis cannot be conclusively answered; a larger sample size and further studies on other influencing factors would have been required. In addition, the procedure would need to be highly standardized, as both sampling localization and hair colour appear to have an influence.

This study investigated the hypothesis that a natural biopolymer system could simultaneously mitigate and detect aflatoxin M1 (AFM1) contamination in milk. AFM₁, the hydroxylated metabolite of aflatoxin B₁, is a potent carcinogen that remains stable during milk processing and continues to pose significant food safety concerns. The research therefore aimed to determine the prevalence of moulds and AFM1 in raw buffalo and cow milk from Giza Governorate, Egypt, and to evaluate the performance of a novel natural biopolymer complex composed of chitosan, β-cyclodextrin, AFM₁-specific antibodies and anthocyanins, designed for dual functionality in AFM₁ adsorption and diagnostic signal enhancement. Total mould counts were assessed following the ISO protocol, while milk composition and somatic cell count (SCC) were determined by Bentley 150 scan. AFM1 detection was initially performed by thin-layer chromatography (TLC) and subsequently quantified by a validated reversed-phase high-performance liquid chromatography (HPLC) method. The HPLC method exhibited excellent performance with linearity (R2 = 0.99999), sensitivity (LOD 0.002 µg/L, LOQ 0.007 µg/L) and precision (RSD ≤ 1.5%). The lowering in milk compositional quality was statistically significant (P < 0.05) with elevated SCC in AFM₁-positive samples. Screening revealed AFM1 contamination in 28% of buffalo and 56% of cow milk samples, with mean concentrations of 0.084 µg/L and 0.188 µg/L, respectively. Application of the natural biopolymer achieved AFM1 reductions of 65–73% in buffalo milk and 83–90% in cow milk, while anthocyanins within the polymer provided concentration-dependent diagnostic signals. Sensory evaluation indicated that treated milk maintained acceptable organoleptic properties without adverse effects on compositional quality. These findings emphasise the prospective use of natural biopolymers as dual-function analytical and mitigation tools for AFM1 in milk, offering a reliable approach for routine milk safety monitoring.

This study aimed to evaluate the microclimatic conditions of natural shading provided by Ipês (Handroanthus heptaphyllus [Vell.] Mattos), and of an artificial shading structure characterized by the combination of an aluminized net on the outside and a black polypropylene net on the inside. In addition, their effects were analysed with respect to the physiological and behavioural responses of Holstein cows kept at pasture in a tropical climate. Two paddocks were used, one with trees and the other with trees and an artificial shade structure. Eight multiparous cows were evaluated over 20 non-consecutive days and selected according to their predominant coat colour: four with predominantly white coats and four with predominantly black coats. The experimental days were classified as very hot, with radiation above 625 Wm−2; and hot days, with radiation between 300 and 625 Wm−2. The mean radiant temperature (°C), the radiant heat load (Wm−2) and the black globe humidity index were calculated. The mean radiant temperature for artificial shading was lower for all days (P < 0.05), with values below 30°C during daylight hours. The radiant heat load was lower under the artificial shading structure regardless of the day (P < 0.05), with values below 470 Wm−2. When compared microclimatically with natural shading, artificial shading was more efficient (P < 0.05) in reducing mean radiant temperature and radiant heat load. Although behavioural variation (P < 0.05) was observed, these results were related to the difference in coat pattern. Animals with predominantly black coats grazed in the early morning hours and sought protection as thermal comfort levels rose.

This Research Paper investigates the hypothesis that variations in genes related to immune system function may influence the antioxidant potential of cow milk. The present study analysed the association between genotypes at selected osteopontin (OPN), chemokine receptor type 1 (CXCR1) and L-selectin (SELL) gene loci and the total antioxidant capacity of milk from 519 Polish Holstein–Friesian black-and-white cows. Genotyping at the genomic loci employed the polymerase chain reaction-restriction fragment-length polymorphism method, while the Trolox-equivalent antioxidant capacity method was used to measure milk TAC. The statistical method involves analysis of variance with Dunnett's post hoc tests. The results of analyses showed that the chosen genotypes as a TT (CXCR1 – c.291C > T), TT (CXCR1 – c. + 365 T > C) and TT (SELL – c.567C > T) combination was significantly associated with higher mean milk antioxidant capacity (P < 0.039). Therefore, analysing polymorphisms in genes related to the bovine immune system appears to be important in the context of selecting animals that produce milk with enhanced functional properties.

This research communication aimed to describe the concentrations of major bone metabolic markers in colostrum from dairy cows on the day of calving and to clarify their associations with parity and the incidence of milk fever (MF). Forty-five Holstein cows were categorized into three groups based on parity: P1 (first calving; n = 18), P2 (second calving; n = 11) and P3 (third to sixth calving; n = 16). Within the P3 group, 6 cows developed MF within a few hours after calving (MF cows), whereas 10 showed no signs of MF (non-MF cows). Concentrations of osteoprotegerin (OPG), tartrate-resistant acid phosphatase isoform 5b (TRAP5b), cross-linked N-telopeptide of type I collagen (NTx), bone-specific alkaline phosphatase (BAP or ALP3) and calcium (Ca) were measured. With increasing parity, serum concentrations of Ca, ALP3 and TRAP5b significantly declined (P < 0.001–0.05). Parity also significantly influenced colostral bone markers: colostral BAP was highest in the P2 group (P < 0.01). Among P3 cows, serum Ca concentrations were significantly lower in MF cows than in non-MF cows, although no significant differences were observed in colostral Ca concentrations. Although no statistically significant differences were detected in other colostral bone metabolic markers between MF and non-MF cows, colostral OPG concentrations tended to be higher in MF cows (P = 0.088). Across all 45 cows and within the P3 group, colostral OPG was moderately and positively associated with serum OPG, as well as with both colostral and serum NTx concentrations. In conclusion, colostral OPG concentration in parturient cows with three or more parities may serve as a useful indicator for reflecting the bone metabolic status of dairy cows with and without MF.

This study aimed to evaluate the effects of cashew nut shell liquid (CNSL) levels in goats’ diets on their performance and milk quality. We hypothesize that the inclusion of CNSL in lactating goats’ diets may influence the biohydrogenation process, increasing the levels of CLA (i.e., C18:2-c9 t11 isomer) and its precursors (rumenic acid, C18:1-t11) in goat milk. Eight lactating Saanen goats were assigned to a replicated 4 × 4 Latin square design with four diets: a control diet with no inclusion of CNSL and diets with the inclusion of 5, 15 and 20 g of CNSL per kg/dry matter. Intake of major nutrients was not different between diets, and no difference was observed in apparent total-tract digestibility of nutrients, except that ether extract intake increased linearly (P < 0.001) with CNSL inclusion rate. Milk yield (2.39 kg/day) and milk composition were not affected by the inclusion of CNSL. The milk fatty acids (FAs) C18:1-t9 (P = 0.001) and C18:3-n3 (P = 0.007) presented higher concentrations in milk with CNSL inclusion. The partial sum of omega-3 FA (Σn3), PUFA/SFA ratio and n6:n3 and n3:n6 ratios showed linear responses (P < 0.05) with increasing levels of CNSL. In conclusion, the CNSL affected the milk lipid profile in a way that is favourable to human health. CNSL may be a viable strategy to enhance milk with bioactive FAs.

The trend towards health-conscious consumption has led the food industry to enhance the nutritional content of staple products like yoghurt. This review explores the integration of nutrient-rich fruit peels into yoghurt, emphasizing both health benefits and technological advancements. Fruit peels, which are frequently discarded as agro-industrial waste, are abundant in nutrients, antioxidants and dietary fibres, which can boost yoghurt's nutritional profile. Incorporating fruit peels not only supports waste reduction and sustainability but also contributes to the added value of yoghurt products. Technological innovations have made it possible to efficiently process and incorporate these peels while preserving their benefits. The review evaluates various methods such as fermentation, drying and grinding and their effects on yoghurt's taste, texture and shelf-life. Additionally, it considers consumer acceptance and market potential for these enhanced yoghurts. Overall, this approach highlights the promise of fruit peels as functional ingredients, promoting health benefits and advancing yoghurt production technologies.

The aim of this study was to develop a fermented dairy beverage based on buttermilk, enriched with prebiotic fibre and supplemented with protein, and to evaluate its physicochemical and microbiological properties. Four treatments were formulated: control (T1), inulin (T2), whey protein (T3), and inulin plus whey protein (T4). During 36 days of refrigerated storage, pH, titratable acidity, syneresis, protein content, lactic acid bacteria count, and rheological behaviour were evaluated. Treatments T1 and T2 exhibited minimal differences across all parameters, confirming the feasibility of adding inulin to dairy beverages without altering their characteristics. Treatments T3 and T4 showed significant differences in all parameters except microbial counts, displaying higher pH, titratable acidity, protein content, and viscosity, and lower syneresis, highlighting the influence of protein supplementation on product properties. Overall, the results demonstrated that the use of buttermilk to produce dairy beverages is promising and may lead to a new variety of healthy products for consumption.

Mastitis management in automatic milking systems (AMS) is challenging, as detection of clinical signs relies on sensors. Treatment recommendations for clinical mastitis (CM) advise conducting microbiological cultures of the infected quarter whenever possible to guide therapy. The objective of this study was to evaluate the association between the use of a rapid diagnostic mastitis pathogen chromogenic culture test on the CM case duration and the probability of more than one treatment before cure. A total of 106 CM cases from 65 dairy cows housed in a freestall AMS barn were retrospectively analysed: 25 treated according to chromogenic culture results and 81 without pathogen identification. All cases were pre-identified using AMS-derived milk parameters, confirmed through veterinary examination, and followed by weekly veterinary examinations until cure. Generalized mixed linear models were used to assess the association between chromogenic culture use and the outcomes, with confounders included as covariates. The use of a chromogenic culture reduced mastitis case duration by 2.78 ± 1.26 days compared to treatment without chromogenic culture. There was no effect on the likelihood of affected cows receiving more than one treatment for CM. The use of a chromogenic culture reduced CM time-to-cure in an AMS freestall dairy herd.

As breeding has become increasingly specialized over the last decades, modern dairy breeds have mainly been focusing on milk production, producing bull and surplus female calves with low economic value. To address this dilemma, the present study evaluates how crossbreeding with the specialized beef breed Belgian Blue and pure breeding with Holstein-Friesian bulls affect calving ease and subsequent fattening performance, and carcass quality in Holstein-Friesian herds. For the study, pedigree information, calving information, as well as fattening performance and carcass quality parameters of 5,162 fattening bulls sired by either Holstein-Friesian (n = 4,607) or Belgian Blue (n = 555) sires from Holstein-Friesian cows in northern Germany were considered. Crossbred calves had higher birth weights and better carcass conformation ratings but also higher age at slaughter, carcass weight and average daily weight gain than purebred dairy calves, reflecting beef breeds’ superior muscle development. However, crossbreeding with Belgian Blue sires also increased the frequency of difficult births (dystocia), which has previously been shown to negatively impact calf health. The effect of parity was not relevant for fattening and carcass quality parameters but highlighted the present breeding practice of using beef sires in multiparous rather than in primiparous cows. Seasonal variations were also observed, with spring and summer-born bulls exhibiting faster weight gain.