Dairy, Volume 6, Issue 4 (August 2025) – 18 articles

Use of sedation for disbudding is common practice in a number European countries, with United Kingdom (UK) practices adopting its use. This study assessed the effects of disbudding with and without xylazine sedation on growth rates and calf health on a UK calf rearing unit. Data was collected from 485 dairy crossed with beef breed calves between April and August 2024 from a single calf rearing unit in England. Calves were purchased from multiple farms across the UK and arrived on site at approximately 21 days of age. Calves were disbudded—and, in the case of male calves, surgically castrated—at approximately three weeks after arrival on farm. Pens of calves were assigned to undergo disbudding with (SED, n = 238) or without (CTL = 234) xylazine sedation at a dose of 0.2 mg/kg administered intramuscularly. Calves from both groups were provided with local anaesthetic (procaine hydrochloride) as a cornual nerve block and a non-steroidal anti-inflammatory drug (meloxicam). While other studies have demonstrated some behavioural and physiological indicators of pain to be reduced with sedation, this study found that calves in the SED group had a reduced daily liveweight gain (DLWG) of 0.14 kg/day in the short term (mean 20 days) following disbudding (p < 0.001), but there was no difference in growth rates in the medium-term (mean 43 days) post-disbudding (p = 0.30). Some of this difference could be explained by the slightly higher DLWG pre-disbudding in the CTR group, and it is likely that the physiological impacts of sedation accounted for the rest of this difference. This initial reduction in DLWG following disbudding with sedation should be considered by vets, especially on farms where growth rates may already be compromised. In the sedated calves, 19.3% exhibited either some movement or entry into sternal recumbency. Specifically, a light plane of sedation with calves entering sternal recumbency was associated with a reduction in DLWG of 0.89 kg/day compared to 0.98 kg/day for those that remained in lateral recumbency throughout (p = 0.008). The light plane of sedation may have created additional calf stress, impacted feeding behaviours, and impinged welfare, with further work needed to establish the reasons for insufficient sedation. There was no difference in the number of post-disbudding treatment outcomes between calves disbudded with and without sedation (p = 0.97). Full article

This study aimed to examine the relationship between a high somatic cell count (SCC) in cows and milk quality during the hot season in different breeds. Milk samples from 500 cows in the hot season and 431 in the cold season of 2022 were collected across 39 farms in Santa Catarina, Brazil. The samples were analyzed for SCC, milk composition, and physical attributes. Cows were also evaluated for udder depth, udder clearance, teat-end condition, and leg and udder cleanliness. Based on the SCC levels, cows were categorized as low (≤200,000 cells/mL), medium (>200,000 and ≤615,000), or high (>615,000). Data were analyzed by ANOVA with a statistical model that included the effects of the SCC class, season, days in milk, parity, genetic group, and the interaction of the SCC level and season. The results showed that cows with a high SCC produced less milk with lower component levels but higher chloride content. Milk from the hot season had lower acidity and reduced component levels. The impact of SCC on the physical traits of milk did not vary with season. Furthermore, cows with deeper udders and lower udder clearance were more likely to have a high SCC, regardless of genetics. Both a high SCC and hot temperatures independently compromised milk yield and quality, thereby increasing the risk of culling. Therefore, improving udder conformation and avoiding cows with deep udders may help to reduce SCC levels. Full article

Maintaining teat-end integrity in dairy cows is essential to preventing intramammary infections (IMIs) in dairy cows, yet the relationship between hyperkeratosis, teat conformation, and mammary health remais underexplored. This study evaluated the relationship between teat-end hyperkeratosis, teat conformation traits, microbial colonization, and somatic cell count (SCC) in milk from 170 cows on ten commercial dairy farms in Santa Catarina, Brazil. During two farm visits, milk and teat-end swab samples from paired teats (one with hyperkeratosis, one without) were analyzed for microbial growth and SCC. SCC data were transformed into somatic cell scores (SCS). Results showed no significant association between hyperkeratosis and mastitis microorganisms, although environmental microorganisms tended to be more frequent in hyperkeratotic teats (p = 0.0778). Major microorganisms in milk were significantly associated with higher SCC (p = 0.0132). No relationship was observed between teat conformation traits and hyperkeratosis. These findings suggest that hyperkeratosis may subtly influence the teat canal to environmental bacterial colonization, underscoring the need for improved milking management practices to minimize hyperkeratosis and associated mastitis risks. Full article

The diet of dairy calves can be contaminated with mycotoxins, posing a potential risk to animal health. This case study report aimed to make the first assessment of the presence of multiple mycotoxins in concentrates fed to dairy calves in Brazil. A total of 19 concentrate samples intended for dairy calves were analyzed using liquid chromatography coupled with mass spectrometry. Aflatoxins, deoxynivalenol, and T-2 toxin were not detected in any samples, whereas fumonisins B₁ (FB₁) and B₂ (FB₂) were present in 100% of the samples, with mean concentrations of 2750.1 μg/kg and 834.9 μg/kg, respectively. Zearalenone (ZEN) was detected in 36.8% of samples, with a mean concentration of 929.9 μg/kg. Significant correlations were observed between FB₁ and FB₂ (ρ = 0.978; p < 0.001) and between FB₂ and ZEN (ρ = 0.735; p = 0.05). While the physical form of the concentrate did not influence (p > 0.05) mycotoxin concentrations, a trend was observed for FB₁ (ρ = −0.417; p = 0.07) and FB2 (ρ = −0.395; p = 0.09). These findings highlight the frequent occurrence of Fusarium mycotoxins, likely due to pre-harvest contamination, emphasizing the potential risk of additive or synergistic effects in dairy calves. Full article

Consumer interest in vegetarian, ethical, and clean-label foods is reviving the use of plant-derived milk coagulants. Cardosins from Cynara cardunculus (“thistle”) are aspartic proteases with strong clotting activity, yet their technological impact in cheese remains under-explored. This study compared a commercial thistle extract (PC) with traditional bovine rennet rich in chymosin (AC) during manufacture and 60-day ripening of Caciotta cheese. Classical compositional assays (ripening index, texture profile, color, solubility) were integrated with scanning electron microscopy, three-dimensional surface reconstruction, and descriptive sensory analysis. AC cheeses displayed slower but sustained proteolysis, yielding a higher and more linear ripening index, softer body, greater solubility, and brighter, more yellow appearance. Imaging revealed a continuous protein matrix with uniformly distributed, larger pores, consistent with a dairy-like sensory profile dominated by milky and umami notes. Conversely, PC cheeses underwent rapid early proteolysis that plateaued, producing firmer, chewier curds with lower solubility and darker color. Micrographs showed a fragmented matrix with smaller, heterogeneous pores; sensory evaluation highlighted vegetal, bitter, and astringent attributes. The data demonstrate that thistle coagulant can successfully replace animal rennet but generates cheeses with distinct structural and sensory fingerprints. The optimization of process parameters is therefore required when targeting specific product styles. Full article

Background: Environmental enrichment is a promising strategy to improve the welfare of dairy goats and sheep. However, studies in this field remain scattered, and its effects on productivity are unclear. Objectives: To evaluate the effects of environmental enrichment on behavioral, physiological, and productive parameters in dairy goats and sheep. Data sources: Scopus and Web of Science were searched for studies published from 2010 to 2025. Study eligibility criteria: Experimental or observational peer-reviewed studies comparing enriched vs. non-enriched housing in dairy goats or sheep, reporting on welfare or productivity outcomes. Methods: This review followed PRISMA 2020 guidelines and the PICO framework. Two independent reviewers screened and extracted data. Risk of bias was assessed with the SYRCLE tool. Results: Thirteen studies were included, mostly with goats. Physical, sensory, and social enrichments showed benefits for behavior (e.g., activity, fewer stereotypies) and stress physiology. However, results varied by social rank, enrichment type, and physiological stage. Only three studies assessed productive parameters (weight gain in kids/lambs); none evaluated milk yield or quality. Limitations: Most studies had small samples and short durations. No meta-analysis was conducted due to heterogeneity. Conclusions: Environmental enrichment can benefit the welfare of dairy goats and sheep. However, evidence on productivity is scarce. Long-term studies are needed to evaluate its cost-effectiveness and potential impacts on milk yield and reproductive performance. Full article

Monitoring pH and acidity during yoghurt fermentation is essential for product quality and process efficiency. Conventional measurement methods, however, are invasive and labour-intensive. This study developed artificial neural network (ANN) models to predict pH and titratable acidity during yoghurt fermentation using CIELAB colour parameters (L, a*, b*). Reconstituted milk powder with 12% total solids was prepared with varying protein levels (4.2–4.8%), inoculum concentrations (1–3%), and fermentation temperatures (36–44 °C). Data were collected every 10 min until pH 4.6 was reached. Forty models were trained for each output variable, using 90% of the data for training and 10% for validation. The first two phases of the fermentation process were clearly distinguishable, lasting between 4.5 and 7 h and exceeding 0.6% lactic acid in all treatments evaluated. The best pH model used two hidden layers with 28 neurons (R² = 0.969; RMSE = 0.007), while the optimal acidity model had four hidden layers with 32 neurons (R² = 0.868; RMSE = 0.002). The strong correlation between colour and physicochemical changes confirms the feasibility of this non-destructive approach. Integrating ANN models and colourimetry offers a practical solution for real-time monitoring, helping improve process control in industrial yoghurt production. Full article

The objective of this study was to evaluate the effects of feeding a combination of chicory–plantain silage and supplementing Se yeast on the response of early-lactating ewes to induce subclinical mastitis. Polypay ewes (n = 32) were fed either chicory–plantain silage or grass silage and supplemented with 3.6 mg Se yeast/ewe/day for approximately 2 months prior to the infusion of S. uberis into both mammary glands (i.e., intramammary infection or IMI). The ewes had a typical subclinical mastitis response with an 8-fold increase in milk somatic cell count within 24 h post-IMI, a decrease in milk yield, and changes in all milk components measured. The ewes experienced a mild systemic inflammation post-IMI as determined by an increase in rectal temperature and decrease in feed and water intake and, in blood, by an increase in the concentration of ceruloplasmin, haptoglobin, and myeloperoxidase and a decrease in paraoxonase, Zn, advanced oxidation protein products, and hematocrit with no effect on pro-inflammatory cytokines. No effect of silage type, likely due to a low concentration of secondary compounds, or Se supplementation was detected in response to IMI. In summary, the subclinical mastitis model used was effective in mounting an inflammatory response, although this was mild; however, feeding chicory–plantain silage with a low concentration of secondary compounds and supplementing Se yeast had no significant effect on the response of ewes to mammary infection. Full article

This on-farm study evaluated the effects of a regenerative (plant polyculture) as compared to conventional (monoculture) pasture-based New Zealand dairy production system on milk and yoghurt nutraceutical properties and environmental impact. Milk and yoghurt produced by two adjacent regenerative and conventional farms were sampled throughout the year and analyzed for chemical composition, metabolomics, and microbiome. Milk samples were also collected over four consecutive days (one day after herbage sampling) on four occasions throughout lactation: early lactation (October), peak lactation (December/January), mid-lactation (March), and late lactation (May). Overall, the regenerative system had a lower environmental impact while maintaining a similar yield and the same milk composition compared to conventional systems. Furthermore, milk and yoghurt from the regenerative system had a more favourable profile of phytochemical antioxidants with potential positive benefits to human health (anti-inflammatory and antioxidant). Full article

Infrared thermography (IRT) is explored as a non-invasive method for indirectly measuring parameters related to animal performance and welfare. This study investigates a feature extraction method termed the “thermal signature” (TS), a descriptor vector derived from the temperature matrix of an animal’s body surface, representing the percentage distribution of temperatures within predefined ranges. The TS, combined with environmental data, serves as a predictor attribute for machine learning-based classifier models to assess heat stress levels. The methodology was applied to a dataset collected from two groups of five dairy calves housed in a climate-controlled chamber and exposed to two artificial heat waves over 13 days. Data, including IRT measurements, respiratory rate (RR), rectal temperature (RT), and environmental variables, were collected five times daily (from 6 a.m. to 10 p.m., every four hours). Classifier models were developed using random forest (RF), support vector machine (SVM), artificial neural network (ANN), and K-nearest neighbor (KNN) algorithms. The RF models based on RR achieved the highest accuracies, 94.1% for two heat stress levels and 80.3% for three heat stress levels, using TS configurations with six temperature ranges. The integration of TS with machine learning-based models demonstrates promising results for developing or enhancing classifiers of heat stress levels in dairy calves. Full article

To study behavioral and productive factors to detect changes that may indicate and predict clinical mastitis cure, Holstein dairy cows (n = 60), in an automatic milking system (AMS) and equipped with behavioral monitoring collar, were monitored from the diagnosis of clinical mastitis (D0) until clinical cure. The parameters collected through sensors were feeding activity, milk electrical conductivity (EC), milk yield, Mastitis Detection Index (MDi), milk flow, and number of gate passages. Clinical mastitis cases (n = 22) were monitored and divided into cured cases (n = 14) and non-cured cases within 30 days (n = 8), paired with a control case group (n = 28). Cows were assessed three times per week, and cure was determined when both clinical assessment and California Mastitis Test (CMT) results were negative in three consecutive evaluations. Mixed generalized linear regression was used to assess the relationship between parameters and clinical mastitis results. Mixed generalized logistic regression was used to create a predictive model. The average clinical cure time for cows with clinical mastitis was 11 days. Feeding activity, gate passages, milk yield, milk flow, EC, and the MDi were associated with cure. The predictive model based on data from D0 showed an Area Under the Curve of 0.89 (95% CI = 0.75–1). Sensitivity and specificity were 1 (95% CI = 1–1) and 0.63 (95% CI = 0.37–0.91), respectively. The predictive model demonstrated to have good internal sensitivity and specificity, showing promising potential for predicting clinical mastitis cure within 14 days based on data on the day of clinical mastitis diagnosis. Full article

Serra da Estrela cheese (a raw ewe’s milk) ripened for 45 days was treated at 600 MPa for 6 min (P1) and at 450 MPa for 6 (P2) and 9 min (P3) and kept in refrigerated storage for 15 months. Lactobacillus and Lactococcus viable cell numbers were reduced in 3.2–3.6 and 2.7–3.6 log cycle units, respectively. Lower reductions were verified for total aerobic mesophilic and Enterococcus viable cell numbers in cheeses treated at 450 MPa (2.4–2.5 and 1.2 log reductions, respectively). In HPP cheeses, yeasts and moulds were below the enumeration limit up to 6 months of storage, but at 15 months 3.6–4.2 log cfu/g were quantified in all cheeses, while Enterobacteriaceae were inactivated to below the quantification limit. The increment of pressure treatment caused a greater impact on the microbiota’s viability than the increase in time under pressure. During storage, minor total colour differences were determined for HPP P3 cheese surface relative to control cheeses, Ch_C, at 45 days of ripening. HPP can thus be a good process to apply after cheese manufacture, since it offers a good potential to render raw-milk cheese microbiologically safer, with minimal changes in quality. Full article

Milk quality has a growing importance for farmers as component-based pricing becomes more widespread. Food quality and precision manufacturing techniques demand consistent milk composition. Udder health, general cow condition, environmental factors, and especially feed composition all influence milk quality. The large volume of routinely collected milk data can be used to build prediction models that estimate valuable constituents from other measured parameters. In this study, casein was chosen as the target variable because of its high economic value. We developed a multiple linear-regression model and a feed-forward neural network model to estimate casein content from twelve commonly recorded milk traits. Evaluated on an independent test set, the regression model achieved R² = 0.86 and RMSE = 0.018%, with mean bias = +0.003% and slope bias = −0.10, whereas the neural network improved performance to R² = 0.924 and RMSE = 0.084%. In silico microgreen inclusion from 0% to 100% of dietary dry matter raised the predicted casein concentration from 2.662% to 3.398%, a relative increase of 27.6%. To extend practical applicability, a simulation module was created to explore how microgreen supplementation might modify milk casein levels, enabling virtual testing of dietary strategies before in vivo trials. Together, the predictive models and the microgreen simulation form a cost-effective, non-invasive decision-support tool that can accelerate diet optimization and improve casein management in precision dairy production. Full article

This study evaluated the effects of supplementing early-lactation Holstein cows with rumen-protected omega-3 fatty acids (calcium salts) on productive and reproductive performance. Thirty-six multiparous cows were randomly assigned to one of two treatments from 21 ± 2 days before calving to 105 ± 5 days in milk (DIM): a Control group (C) or an Omega-3-supplemented group (O-3), receiving a blend of linseed and fish oil (60:40). Both groups were fed isoenergetic diets, with ground corn as the control supplement. Total dry matter and net energy intake did not differ between treatments. A treatment-by-time interaction was observed for milk yield, with cows in the O-3 group producing more milk than controls at specific time points. Additionally, O-3 cows had higher overall protein yield and improved feed efficiency. No differences were found in body weight, BCS, glucose, insulin, IGF-1, or urea concentrations, but a tendency toward higher plasma NEFA and BHBA concentrations and lower energy balance was observed in the O-3 group. Supplementation increased plasma cholesterol and progesterone concentrations and was associated with a higher proportion of cows being pregnant at 130 DIM. These findings suggest that omega-3 supplementation may improve specific aspects of lactational performance and reproductive efficiency without compromising metabolic status. Full article

The objective of this work was to explore the effect of taxonomically and phytochemically rich swards, as opposed to ‘status quo’ monoculture of ryegrass and white clover swards, on animals and milk, by assessing the metabolomic profile of plant and milk samples. The results of this study suggest that metabolomic profiles and metabolism are altered by dietary diversity and grazing management. Several metabolites associated with enhanced consumer health were elevated in milk from cows that were grazed in functionally diverse swards as opposed to monoculture of ryegrass and white clover swards. The results show the value of metabolomics for the identification of metabolites associated with a ‘pasture-fed diet’, which is considered beneficial to human health compared with grain-fed milk products. Metabolomics also provide evidence that grazing management and the presence of key forages may be more beneficial for market differentiation of milk products that can enhance consumer health than maximisation of sward species diversification. Full article

Requesón, a Mexican whey cheese, has a short shelf life due to its high moisture content, near-neutral pH, and the limited preservation infrastructure of the artisanal cheese sector. Therefore, the development of requesón powder provides an innovative pathway to enhance market potential and expand its applications. This study aimed to evaluate the techno-functional properties of requesón powder produced through air-convective drying and to assess the protective effects of two natural gums, mesquite gum and guar gum, at concentrations of 0.25 and 0.5 g/L. Thermal dehydration significantly affected (p < 0.05) water holding capacity, swelling capacity, and hardness of the reconstituted powder. Although gum addition did not significantly enhance water holding capacity, it moderately improved texture and led to notable increases in swelling capacity (21–34%) and emulsifying capacity (11–20%) at high concentrations (p < 0.05). Structural analyses using X-ray diffraction and electron microscopy revealed that thermal dehydration induced protein aggregation and reduced microporosity, impairing rehydration performance compared to requesón powder obtained by lyophilization. These findings suggest that requesón powder production is a promising strategy for valorizing whey and extending the applications of this traditional cheese as a functional food ingredient. Full article

Consumer scrutiny of fat content in foods is becoming a notable trend in health concerns. This study aims to develop a novel functional low-fat goat feta cheese by utilizing polydextrose (PDX) and inulin as dietary fiber-based fat replacers to improve its overall characteristics. The physicochemical and textural properties, along with consumer acceptance, of the feta cheese were evaluated across three fat levels (full-fat [FFC], reduced-fat [RFC], low-fat [LFC]) and three fibers: PDX, inulin, and their combination. The intercorrelation of all characteristics was assessed through principal component analysis and Pearson’s correlation. Fat reduction significantly altered the cheese’s visual properties, increasing lightness and the total color difference, which inversely correlated with a* and b* values. Lower-fat cheeses exhibited decreased pH and increased lactic acid, with salinity playing a crucial role in both lactic acid development and texture. Under Scanning Electron Microscopy (SEM), PDX yielded a cheese matrix with a finer pore structure than inulin or the combined fibers. Lower-fat cheeses exhibited greater hardness, with PDX resulting in the highest hardness among the fiber treatments. Crucially, the RFC with PDX was as well-received by consumers as the FFC. These findings not only empower goat farmers and cheese entrepreneurs to increase their product value for niche market but also contribute to sustainability by providing a healthier food option for functional benefits. Full article

In this study, Malatya cheeses were produced using cow’s milk, sheep’s milk, and a cow–sheep milk mixture (1:1), were stored in brine solutions, and samples from both the cheeses and their brines were collected and analyzed at 0, 30, 90, and 180 days of storage to investigate the impact of the milk type and storage time on the cheese characteristics. Cheese made from cow’s milk exhibited a lower fat content (14.5%), whereas cheese made from sheep’s milk had a lower protein content (17.5%). During storage, salt and ash contents increased. Water-soluble nitrogen (WSN) and trichloroacetic acid-soluble nitrogen (TCASN) levels decreased during the first 90 days of storage, followed by a subsequent increase. Cow’s milk cheese demonstrated higher ripening extension index (REI) values, indicating early-stage proteolysis, whereas sheep milk cheese showed higher ripening depth index (RDI) values, reflecting more advanced ripening. The total concentration of volatile compounds in the headspace increased over time, rising from 576.7–1060.2 to 5795.1–7360.1 µg/kg dry matter by day 180 of storage, with acids being the dominant volatile group in both quantity and diversity. Free fatty acids (FFAs) were the predominant volatiles and branched-chain acids and alcohols associated with proteolysis were particularly notable in cow’s milk cheeses. Additionally, the transfer of proteins and volatile compounds into the brine increased throughout the storage period. Overall, storage time significantly influenced the cheese characteristics, while milk type also played a role, albeit to a lesser extent. Full article