Dairy Research Bulletin: Selected Articles from August 2025

Environmental Management and Sustainability

How do production practices and climate change impact the water footprint of dairy farms? Palhares JCP, De Souza DP, Carra SHZ, Drastig K. Sci Total Environ. 2025 Aug 18;998:180243.

Understanding water use in dairy production systems is crucial to promoting production practices and enhancing resilience to climate change.
The study aimed to evaluate how production practices and climatic scenarios in different dairy farming systems influence the water footprint of milk production.
A total of 67 dairy cattle farms were selected for the study. Climatic scenarios and production practices were proposed as farm-specific interventions targeting three key areas: animal feed, effluent treatment, and nitrogen field application.
For all production systems, the combinations exhibiting the highest water efficiency were characterized by the following factors: for green water, a 25 % increase in corn and soybean yields; for blue water, a reduction in milking parlor washing water consumption, an increase of 1 liter of milk per cow per day, and/or a reduction of 1 kilogram in dry matter intake per cow per day; and for grey water, the treatment of effluent from the milking parlor.
Conversely, the combinations with the lowest water efficiency were identified as follows: for green water, maize yields decreased by 15 % and soybean yields increased by 12.95 %; for blue water, an increase of 1.5 °C to 2.5 °C in minimum daily temperature and/or a reduction of 1 kilogram in dry matter intake per cow per day; and for grey water, the non-treatment of effluent with the maximum value of α.
The findings of this study establish production practices in water scenario analyses concerning water footprints in dairy cattle production systems.

Glass half full: A framework for setting realistic water quality conservation targets. Summers H, Eckberg JO, Peterson HM.J Environ Qual. 2025 Aug 7.

A case study was launched to quantify potential water quality benefits attainable through practical and realistic conservation implementation targets. The Lake Michigan Basin was selected because of its importance as a dairy, grain, and oilseed production region that supports a range of ecosystems and endangered species.
The objective was to build a framework, implementing a widely accessible tool that could be applied by local conservation staff to set practical, watershed-level, clean water targets.
The US Environmental Protection Agency’s Pollutant Load Estimation Tool, which is free and provides a user-friendly web interface, was applied to quantify phosphorus and sediment load reduction from six conservation scenarios in each Hydrologic Unit Code-8 watershed.
Conservation scenarios included rotational grazing, cover crops, conservation tillage, nutrient management, prairie strips, and a combination of the practices referred to as “regenerative agriculture.” Each scenario was compared to a baseline of current cover crop and conservation tillage adoption rates, established using remote sensing data.
The model estimated that implementing the regenerative agriculture scenario, which would require an additional 2640 km2 of conservation and $260 million in investment, could reduce phosphorus loads by 21% and sediment loads by 10% compared to current loading.
Results confirm that conservation investments by multiple stakeholders at the federal, state, and local levels can result in meaningful impacts to achieve water quality goals. This framework can be applied to other regions with minimal data inputs, making it a scalable approach to guide collective action toward water quality conservation targets.

Treatment of Dairy Wastewater Retentate After Microfiltration: Evaluation of the Performance of the System Based on Activated Sludge and Activated Carbon. Życki M, Barszcz W, Łożyńska M. Membranes (Basel). 2025 Aug 6;15(8):237.

The dairy industry generates significant amounts of wastewater, including microfiltration (MF) retentate, a byproduct thickened with organic and inorganic pollutants.
This study focuses on the treatment of two times concentrated MF retentate using a hybrid system based on biological treatment in a sequential batch reactor (SBR) and adsorption on activated carbon.
The first stage involved cross-flow microfiltration using a 0.2 µm PVDF membrane at 0.5 bar, resulting in reductions of 99% in turbidity and 79% in chemical oxygen demand (COD), as well as a partial reduction in conductivity.
The second stage involved 24-h biological treatment in a sequential batch reactor (SBR) with activated sludge (activated sludge index: 80 cm3/g, MLSS 2500 mg/dm3), resulting in further reductions in COD (62%) and TOC (30%), as well as the removal of 46% of total phosphorus (TP) and 35% of total nitrogen (TN).
In the third stage, the decantate underwent adsorption in a column containing powdered activated carbon (PAC; 1 g; S_(BET) = 969 m2 g-1), reducing the concentrations of key indicators to the following levels: COD 84%, TOC 70%, TN 77%, TP 87% and suspended solids 97%. Total pollutant retention ranged from 24.6% to 97.0%.
These results confirm that the MF-SBR-PAC system is an effective, compact solution that significantly reduces the load of organic and biogenic pollutants in MF retentates, paving the way for their reuse or safe discharge into the environment.

Impact of management practices on nitrous oxide emissions in an irrigated dairy forage rotation. Dungan RS, Leytem AB, Miito GJ. J Environ Qual. 2025 Aug 6.

Nitrous oxide emissions from semiarid, irrigated cropping systems are strongly influenced by tillage, nutrient source, and cover cropping, yet their long-term interactive effects remain underexplored.
Researchers quantified N2O emissions from a continuous silage corn (Zea mays) system under factorial combinations of tillage (conventional vs. reduced), nitrogen source (dairy manure vs. synthetic fertilizer), and winter cover cropping (triticale vs. fallow) over 3 years (2021-2023) following 6 years of prior treatment implementation.
Dairy manure solids were applied annually in the fall from 2015 through 2020. No further manure applications were made, and from spring 2021 onward, N2O fluxes were monitored to assess legacy effects. Fluxes were monitored weekly using vented, nonsteady-state chambers.
Emissions were episodic, with peak emissions occurring after irrigation onset and during winter months. In 2021, reduced tillage plots produced 25% greater cumulative emissions than CT (3.3 vs. 2.7 kg N2O-N ha-1; p = 0.030), though no tillage differences were observed in subsequent years following a field-wide moldboard plowing in spring 2022.
Manure-treated plots consistently produced the highest emissions, exceeding synthetic fertilizer treatments by 723%, 267%, and 147% in 2021, 2022, and 2023, respectively (p < 0.0001). Winter cover cropping lowered preplant soil nitrate but did not reduce N2O losses in manured soils, likely due to continued in-season mineralization.
These results show that manure legacy effects persist after applications end and that tillage impacts on emissions are short-lived. Optimizing nutrient use and reducing emissions in semiarid irrigated systems will require integrated management of manure, tillage, and irrigation.

Long-term impacts of untreated dairy manure on the microbiome and Shiga toxin-producing Escherichia coli persistence in agricultural soil. Richter TKS, Kauffman M, Leonard SR, et al. Appl Environ Microbiol. 2025 Aug 7:e0044725.

Shiga toxin-producing E. coli (STEC), including E. coli O157:H7, is a major etiological agent of foodborne human disease outbreaks associated with fresh produce and can be transferred to produce via contaminated agricultural soil. Given the devastating impacts of foodborne STEC outbreaks on public health and growers, it is necessary to understand the longevity of the impacts of manure application on the pathogen risk in the soil as well as better understand the ecological and environmental conditions that contribute to STEC survival in the agricultural soil environment.
Biological soil amendments of animal origin (BSAAO) improve the soil health of agricultural fields for plant growth. However, as natural reservoirs for bacterial foodborne pathogens, BSAAO application can introduce and support microbes of public health concern, such as pathogenic STEC, in agricultural soils.
Using shotgun metagenomic sequencing, this project investigated the microbiome of soil with and without BSAAO, focusing on STEC and the E. coli population over time alongside changes in the soil microbiome and soil abiotic properties.
Two farms in Ohio, one using an untreated dairy manure amendment and one that does not use a BSAAO, were sampled for over a year for metagenomic analysis of the soil microbiome.
All manure samples were positive for stx genes, indicating the presence of STEC. Impacts of the manure on the soil lasted four weeks by several measures including higher E. coli diversity and more frequent STEC detection. Outside of these four weeks post-amendment, Shiga toxin genes (stx) were identified periodically in both fields throughout the year.
STEC detection significantly correlated with lower soil cation exchange capacity and concentrations of calcium, magnesium, and organic nitrogen. Differential abundance analysis of the soil metagenomes identified several taxa influenced by amendment but did not identify taxa correlated with detection of stx genes.
This work expands upon the knowledge of conditions that support STEC persistence in the produce-growing environment and its longevity following amendment in commercial fields with naturally occurring STEC contamination.

Impacts of cellulase and xylanase addition on antibiotic resistance and microbial community during dairy manure composting. Gong P, Zhou Y, Jin E, et al. PLoS One. 2025 Aug;20(8):e0328055.

Composting is a transformation and biodegradation process that converts organic biomass into valuable products while also removing antimicrobial resistance genes (ARGs). Promoting lignocellulose biodegradation is essential for enhancing composting efficiency and improving the quality of compost derived from agricultural organic waste.
This study aims to explore the effects of cellulase and xylanase on the composting process of cow manure, with a focus on their impact on key physicochemical properties, microbial communities, and antibiotic resistance genes (ARGs).
Dairy manure compost was carried out for 30 days with cellulase and xylanase treatment. The physicochemical characteristics (pH, organic matter (OM), total nitrogen (TN), available nitrogen (AN), germination index (GI), humic acid (HA), and fulvic acid (FA)) of the compost samples were measured, along with enzymatic activities, including cellulase activity (CA), urease activity (UA), alkaline phosphatase (ALP), and dehydrogenase activity (DHA).
Enzyme additions significantly enhanced composting efficiency, which improved temperature regulation and increased nitrogen content. Cellulase notably accelerated the degradation of organic matter, enhanced microbial diversity, and reduced ARG abundance, while xylanase played a crucial role in stabilizing pH and temperature during the later stages, facilitating nitrogen retention and compost maturity.
Additionally, microbial community dynamics were closely linked to ARG patterns, indicating that enzymatic treatments can optimize composting processes while mitigating the spread of resistance genes.
The findings highlight the complementary roles of these enzymes in improving composting outcomes and suggest strategies for sustainable waste management. These findings provide valuable insights for improving the composting efficiency and quality of compost derived from agricultural organic waste.

Reducing crude protein content in the diet of lactating dairy cows improved nitrogen-use-efficiency and reduced N excretion in urine, whilst having no obvious effects on the rumen microbiome. Zeleke AW, Dimonaco NJ, Huws SA, et al. J Anim Sci Biotechnol. 2025 Aug 9;16(1):113.

Nitrogen-Use-Efficiency (NUE) in lactating dairy cows, defined as milk nitrogen (N) output as a proportion of N consumed, is low, with the majority of excess N excreted in manure. Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats, and to watercourses contributing to aquatic eutrophication.
While there is much evidence that NUE can be improved by reducing the crude protein (CP) content of dairy cow diets, the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.
This study examined the effects of reducing the CP contents of dairy cow diets on cow performance, NUE, the relationship between NUE and residual feed intake (RFI), and the rumen microbiome.
The results showed that dietary CP content did not affect feed intake, milk yield or milk composition, except for milk urea N (MUN), which increased with increasing diet CP content. The mean NUE was 34%, 34% and 31% for the LCP (low-protein, 15%), MCP (medium-protein, 16%), and HCP (high-protein, 17%) diets, respectively. RFI was negatively correlated with NUE.
The rumen ammonia-N concentrations increased with increasing dietary CP; however, the ruminal pH and volatile fatty acid (VFA) content of the rumen fluid remained constant. Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.
Reducing dietary CP content in dairy cow diets did not affect microbial composition, diversity and functional profiles. The family Bacteroidaceae was more abundant in HE (high-efficiency) cows, whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE (low-efficiency) cows.
Additionally, propanoate metabolism, cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows, whilst the methane (CH4) metabolism pathway was upregulated in LE cows.
The results demonstrate that diet CP can be reduced with no loss in cow performance, but with an associated reduction in N excretion. The abundance of microbial populations differed between low and high efficiency cows, which may contribute to the differences in efficiency observed.

Animal Health and Food Safety

Dairy cattle herds mount a characteristic antibody response to highly pathogenic H5N1 avian influenza viruses. Robinson-McCarthy LR, Simmons HC, McCarthy KR, et al. J Virol. 2025 Aug 25:e0062125.

Establishing human herd immunity ends pandemics. For influenza viruses, this immunity drives continued antigenic evolution that enables viruses to infect once-immune individuals.
An unprecedented outbreak of a highly pathogenic avian influenza virus, H5 clade 2.3.4.4b, was reported in U.S. dairy cattle during the spring of 2024. It has now spread to hundreds of herds across multiple states.
In humans, antibodies to the hemagglutinin (HA) protein confer the strongest protection against infection. Human herd immunity limits viral spread but also drives the emergence of antigenic variants that escape dominant antibody responses.
The researchers used store-bought milk to profile the collective H5N1 antibody response of dairy cattle herds and detected HA binding antibodies in specific samples from states with recent/ongoing outbreaks. These antibodies present in milk neutralized replicating virus expressing dairy cattle HA and neuraminidase (NA).
Despite originating from independent vendors, dairies/plants, geographic regions, and time, antibodies present in these samples are remarkably similar in activity and HA binding specificity. The dominant antibody response was clade 2.3.4.4b HA specific, followed by cross-reactivity with other H5s.
Whether the uniformity of the response is a pathway to achieve herd immunity or an avenue for antigenic variants to rapidly escape remains to be seen. Benchmarking immunity at this phase of the outbreak is important to understand either eradication or the emergence of antigenic variants that enable reinfection.

Emerging H5N1 mutations (PB2-D701N, PB2-E627K, HA-S110N, NA-V116X) in a recent outbreak in U.S. dairy cows: need for continuous monitoring. Chakraborty C, Das A, Bhattacharya M, Islam MA. Ann Med Surg (Lond). 2025 Jul 16;87(8):5347-5350.

Mutations are considered the most critical and fundamental factor in the evolution of viruses. In the H5N1 influenza virus, mutations can significantly alter its behavior, particularly to increase virulence, enhance receptor interaction for entry into the host, and increase resistance to antibodies and drugs.
However, several mutations have been noted in polymerase basic 2 (PB2), hemagglutinin (HA), and neuraminidase (NA). The question is: which mutations are essential among several mutations?
Previously, researchers employed a combination of generative artificial intelligence (GenAI) (large language model or multimodal large language model) and innovative bioinformatics techniques to identify key antibody escape mutations in the S-protein of SARS-CoV-2.
Therefore, AI may be a crucial option for understanding the critical mutations in the H5N1 influenza virus. However, during the report on AI, researchers stated that transparency in AI reporting is an essential component.

H5N1 virus invades the mammary glands of dairy cattle through ‘mouth-to-teat’ transmission. Shi J, Kong H, Chen H, et al . Natl Sci Rev. 2025;12(9):nwaf262.

H5N1 influenza outbreaks have been reported on more than 1070 dairy farms across 17 states in the USA. Damage to the mammary gland and high levels of virus in milk were common features of the infected cattle, but it is unclear how the virus initially invades the mammary glands, and no control strategy is currently available.
Here, researchers report that cattle oral tissues support H5N1 virus binding and replication, and virus replicating in the mouth of cattle transmitted to the mammary glands of dairy cattle during sucking.
The researchers also found that an H5 inactivated vaccine or a hemagglutinin-based DNA vaccine induced sterilizing immunity in cows against challenges with different H5N1 viruses.

Welfare of calves and heifers on dairy farms with cow-calf contact rearing or early separation. Rademann A, Schneider ML, Waiblinger S. Front Vet Sci. 2025 Aug 8;12:1610084.

Early separation (ES) of cow and calf in dairy farming is increasingly questioned due to implications on animal welfare.
The aim of this study was to compare the welfare of animals on commercial dairy farms with cow-calf contact (CCC) or ES using a comprehensive welfare assessment protocol.
Fifty Austrian dairy farms, 25 practicing CCC and 25 ES, were visited. The Welfare Quality® (WQ) Protocol for dairy calves and heifers was used to assess animal welfare. The two rearing systems were compared using a t-test for qualitative behavior assessment (QBA) scores.
CCC calves and heifers scored higher in QBA. CCC calves showed a lower frequency of non-nutritive oral behaviors. Both CCC calves and heifers had more space, were less often disbudded and had more access to pasture. Fewer CCC farms had calves with lesions and heifers with overgrown claws.
Accordingly, rearing systems differed in Criterion and Principle scores. Both CCC calves and heifers scored higher in “Appropriate Behavior” and calves scored higher in “Good housing”. CCC farms had a better WQ classification than ES farms with 20% or 32% of CCC farms reaching “excellent” for calves or heifers compared to 4 or 8%, respectively.
The better welfare of CCC animals may be related to contact to cow(s) but also to other management practices that emphasize animals’ physical and behavioral needs more. Holistic practices prioritizing animal welfare including CCC systems should be considered in the transition toward more sustainable farming.

UC Davis Vet Med Research – Effect of Multi-Species Probiotic Supplementation on Fecal Microbiota in Pre-Weaned Holstein Dairy Calves in California. Lee Y, Rossow HA, Williams DR, Cheong S, Okella H, Widmer L, Okello E. Microorganisms. 2025 Aug 2;13(8):1810.

The gross benefit of feeding multi-species probiotics has been reported, but the effect on the gut microbiota in pre-weaned dairy calves has not been elucidated.
To address this gap, a randomized controlled trial was conducted in California, USA, to investigate the effect of feeding probiotics on the fecal microbiota of pre-weaned dairy calves.
A total of 30 neonatal calves were randomly assigned to either the probiotic (PRO) or control (CON) treatment.
Fecal samples were collected at four age timepoints: days 7, 14, 21, and 42. Fecal bacterial population was analyzed using 16S rRNA amplicon sequencing. Differential abundance analysis was conducted to investigate the difference between the PRO and CON treatments, and diarrheic and non-diarrheic calves in each PRO and CON group.
The PRO group had decreased Clostridium perfringens and Fusobacterium varium compared to the CON at 7 days of age. At 7 days of age, diarrheic calves in CON had more abundant F. varium compared to non-diarrheic calves, but there was no difference between diarrheic and non-diarrheic calves in the PRO group.
In conclusion, probiotics administration decreased the population of pathogenic bacteria in feces from pre-weaned dairy calves on Day 7 of age. However, the treatment did not have an impact on bacterial diversity. These results suggest that the administration of probiotics has the potential to control gastrointestinal pathogens.

Through the Mouth or Nostrils: The Methane Excretion Route in Belching Dairy Cows. Jaimes LJ, Castrillón S, Bustamante BS, Correa HJ. Animals (Basel). 2025 Aug 11;15(16):2350.

Methane is a potent greenhouse gas (GHG) emitted from several anthropogenic sources, most notably enteric fermentation in domestic ruminants, primarily during exhalation. To date, however, it is unclear whether the excretion route of methane exhaled by ruminants occurs through the mouth or nostrils and what the pattern of excretion is; this is important in designing equipment and methods to measure the methane emitted by ruminants.
Thus, the objective of this experiment was to quantify the exhaled methane excreted by dairy cows via the nostrils and mouth while resting, grazing, and ruminating, as well as the pattern of concentration during and between belching.
Four tests were conducted in this study with four dairy cows each. In the first test, resting cows, carrying an electronic spirometry mask (ESM) assembled with a methane sensor in its outlet, were used to measure the concentration of methane in the air expelled through the nostrils and to model the methane concentration between belches; in the second test, a mouth mask was used to measure methane excreted through the mouth; in the third test, an ESM with a methane sensor assembled over the mouth was used to measure methane excreted through the mouth; finally, in the fourth test, a methane sensor was manually placed at 2.0-3.0 cm in front of the mouth of ruminating cows to measure the methane concentration.
In the first test, a pattern of methane concentration between belches was identified, as well as a pattern of the methane concentration and volume of air exhaled during belching.
Methane excretion through the mouth was not detected in any of the tests; hence, it is concluded that dairy cows, while resting, ruminating, and grazing, emit enteric methane only through the nostrils under normal respiration conditions.
This is important in the respiratory physiology of ruminants and in designing equipment and methodology to measure cranial methane excretion.

Environmental Microbiome Characteristics and Disinfection Strategy Optimization in Intensive Dairy Farms: Bactericidal Efficacy of Glutaraldehyde-Based Combination Disinfectants and Regulation of Gut Microbiota. Wang T, He T, Jiang S, et al. Vet Sci. 2025;12(8):707

As the primary biological risk threatening safe dairy production, bovine mastitis control highly relies on environmental disinfection measures. However, the mechanisms by which chemical disinfectants influence host-environment microbial interactions remain unclear.
This study systematically investigated the disinfection efficacy and regulatory effects on microbial community composition and diversity of glutaraldehyde-benzalkonium chloride (BAC) and glutaraldehyde-didecyl dimethyl ammonium bromide (DAB) at recommended concentrations (2-5%), using 80 environmental samples from intensive dairy farms in Xinjiang, China.
Combining 16S rDNA sequencing with culturomics, the results showed that BAC achieved a disinfection rate of 99.33%, which was higher than DAB’s 97.87%, and reduced the environment-gut microbiota similarity index by 23.7% via a cationic bacteriostatic film effect.
Microbiome analysis revealed that BAC selectively suppressed Fusobacteriota abundance (15.67% reduction) and promoted Bifidobacterium proliferation (7.42% increase), enhancing intestinal mucosal barrier function through butyrate metabolism.
In contrast, DAB induced Actinobacteria enrichment in the environment (44.71%), inhibiting pathogen colonization via bioantagonism.
BAC’s long-acting bacteriostatic properties significantly reduced disinfection costs and mastitis incidence.
This study first elucidated the mechanism by which quaternary ammonium compound (QAC) disinfectants regulate host health through “environment-gut” microbial interactions, providing a critical theoretical basis for developing precision disinfection protocols integrating “cost reduction-efficiency enhancement-risk mitigation.”

Effects of different heat treatment processes on the physicochemical properties and structural changes of casein and whey protein from bovine milk. Xiao F, Shi J, Zou Y. J Dairy Sci. 2025 Aug 20:S0022-0302(25)00697-6.

The traditional sterilization methods for milk mainly include low-temperature and long-time pasteurization (63°C/30 min), high-temperature and short-time pasteurization (72°C –95°C/15–20 s), and UHT sterilization (135°C/3–5 s). However, elevated heating temperatures accelerate the degradation of nutrients and microstructures in milk.
The aim of this study was to investigate the effects of different heat treatment processes, infusion technology (INF) and UHT, on the physicochemical properties and structural changes of casein and whey protein from bovine milk.
Two sterilization conditions, INF (156°C to 158°C, 0.09 s) and UHT (135°C, 4 s) to treat bovine milk and isolate whey protein and casein from milk were selected. This study evaluated the particle size, milk composition, and storage stability of different milk samples, and assessed the structural and property changes of proteins.
The results demonstrated that INF milk exhibited smaller average particle size, higher protein, fat, nonfat milk solids, and lactose contents compared with UHT milk. The structure stability and functional properties of casein and whey protein in INF milk were superior to those in UHT milk.
In summary, this study indicated the physical properties of bovine milk under different sterilization conditions, as well as the changes in casein and whey protein in bovine milk. This can provide reference for optimizing the quality and stability of bovine milk products and help develop more functional bovine milk products.

Nutrition and Health

Saturated fat from dairy sources and cardio-metabolic health: insights from the STANISLAS cohort. Wagner S, Girerd N, Michalski MC, et al. Eur J Nutr. 2025 Aug 30;64(6):267.

The health impact of dairy products is debated due to their high saturated fatty acid (SFA) content. Emerging evidence suggests that dairy products intake may reduce cardiovascular disease risk, despite their SFA-rich lipids, leading to the “dairy food matrix” concept. Nevertheless, the impact of lipid and SFA intake from whole dairy sources on cardio-metabolic health remains poorly understood.
This study investigated the cross-sectional association of SFA intake from various types of dairy products and dairy fat sources with cardio-metabolic outcomes.
Data from 1619 participants of the STANISLAS cohort, who underwent extensive metabolic and cardiovascular phenotyping and completed a 133-item food frequency questionnaire covering dairy products and other dairy fat sources, were used.
Associations of total dietary lipid, total dietary SFA, and SFA intakes from dairy products and dairy fat sources with metabolic outcomes (metabolic syndrome, hyperlipidemia, type 2 diabetes, prediabetes) and subclinical cardiovascular damages (i.e., arterial stiffness, atherosclerosis, left ventricular mass, diastolic dysfunction) were assessed using mixed models.
Median lipid consumption via dairy products and dairy fat sources was 23 g/day. Higher total dietary lipid intake was associated with lower arterial stiffness. Total dietary SFA and SFA from dairy products were both inversely associated with left ventricular mass.
SFA from dairy fat sources, particularly from Butter, were inversely associated with hyperlipidemia, hypertriglyceridemia, elevated LDLc, elevated non-HDLc, and elevated Apolipoprotein B. SFA from Yogurt was inversely associated with Apolipoprotein B.
In conclusion, examining the specific dairy matrix subtypes, suggests altogether neutral to beneficial associations of SFA from dairy products and dairy fat sources with cardio-metabolic health.

High-calcium milk improves osteoporosis in postmenopausal women by regulating intestinal flora and steroid hormone biosynthesis. Zhao Y, Li X, Chen L, et al. Front Nutr. 2025 Aug 6;12:1607968.

Postmenopausal calcium loss increases osteoporosis risk in middle-aged and older women. While dairy products are a known calcium source that supports bone health, limited research addresses their specific effects on osteoporosis prevention in this population.
This study aimed to investigate the impacts of consuming milk and calcium intake on measures of osteoporosis in postmenopausal women.
A one-year randomized controlled trial recruited 97 postmenopausal women, randomly assigned to a high-calcium milk group (HCM, 51), consuming 400 mL nutrient-enriched fresh milk daily, or a control milk group (CM, 46), consuming 400 mL of regular fresh milk.
A one-year randomized controlled trial showed that the high-calcium milk group significantly increased lumbar spine bone mineral density (L1-4 BMD), slowed bone loss in the left hip and femoral neck, elevated serum phosphorus and 25-hydroxyvitamin D levels, and modulated the bone formation marker procollagen type I N-terminal propeptide compared with the regular milk group at 6 months.
16S ribosomal ribonucleic acid sequencing showed that high-calcium milk significantly altered the β-diversity of the intestinal flora, increasing the abundance of beneficial bacteria such as Bacteroides, Oscillibacter, and Subdoligranulum, while decreasing the abundance of Firmicutes and Weissella at 12 months.
Metabolomics analysis revealed that high-calcium milk improved bone quality by modulating steroid hormone biosynthesis and arachidonic acid metabolic pathways, and that L1-4 BMD was positively correlated with Faecalibacterium spp. and adenine nucleotide.
This study suggests that high-calcium milk can effectively delay postmenopausal osteoporosis by regulating intestinal flora and metabolic pathways, providing a new target for osteoporosis intervention.

Fermented dairy products intake and stroke risk: analyses of NHANES 2007-2018 data. Ma S, Miao Y, Wu X. Front Nutr. 2025;12:1593174.

Stroke ranks among the main diseases resulting in death and disability, imposing a heavy burden on both the country and individuals. Healthy foods can effectively prevent the occurrence of stroke, and fermented dairy products are among them. However, in previous studies, the correlation between stroke and fermented dairy products remains controversial.
The intake of fermented dairy products and the identification of stroke both originated from the data of the NHANES database from 2007 to 2018. This study used a weighted regression model to analyze the association between the total intake of fermented dairy products and the intake of various types of fermented dairy products (yogurt, cheese and buttermilk) and stroke, and conducted subgroup analyses and interaction tests.
This study included 27,487 American adults, of whom 2.9% had suffered from a stroke. The results of regression analysis indicated that total intake of fermented dairy products and yogurt intake were negatively correlated with stroke.
For total intake, after adjusting for all confounding variables, the results revealed that every 50 g rise in intake led to a 7% decline in the stroke risk. Meanwhile, when compared to participants having no consumption of fermented dairy products, those with a low intake had a 21% lower probability of stroke.
Subgroup analysis showed that smoking interacted with stroke and fermented dairy products. For yogurt, after adjusting for all confounding variables, the results indicated that for every 50 g rise in intake, the probability of stroke declined by 7%. However, only high intake of yogurt was associated with a protective effect against stroke, and this relationship remained stable across three models. In contrast, no significant associations were found between cheese and buttermilk intake and stroke risk.
This study discovered that, among American adults, the total quantity of fermented dairy products as well as yogurt had an inverse correlation with the risk of stroke, while this correlation did not exist for cheese or buttermilk.

Fermented dairy products as sources of bioactive peptides with potential benefits to older adults’ health. Munhóz BA, Baptista DP.Food Res Int. 2025;218:116921. doi: 10.1016/j.foodres.2025.116921.

Aging is a natural process that involves various physiological changes, including increased susceptibility to diseases. With aging, the immune system weakens, and the body becomes more vulnerable to infections and inflammation. Moreover, conditions such as sarcopenia, osteoporosis, and non-communicable chronic diseases (hypertension, type 2 diabetes mellitus, and obesity) are more common among older adults.
However, diet can play a fundamental role in maintaining health and preventing various pathologies. Fermented dairy products, which are rich in high-quality proteins and bioactive peptides, can serve as valuable allies in healthy aging.
These peptides, released during fermentation, ripening, or digestion, exhibit several beneficial activities, including antihypertensive, antioxidant, immunomodulatory, and antidiabetic effects, with the potential to improve the quality of life in older adults.
This review aims to present the benefits of consuming fermented dairy products for the health of older adults, highlighting how the bioactive peptides present in these foods may aid control health conditions associated with aging.
By exploring the processes of fermentation and digestion, and the mechanisms involved in the release of these peptides, the review provides a detailed overview of the potential benefits of consuming fermented dairy products in promoting health and preventing diseases in older adults.

Overall Evidence for Milk-Derived Proteins and Peptides in Blood after Digestion: A Systematic Review. Biondi Ryan MR, Zukaitis J, Sutantawong S, Dallas DC. Nutr Rev. 2025 Aug 29:nuaf118.

Milk and dairy products are rich in protein components, including bioactive peptides and proteins that may play crucial roles in influencing human health. Despite extensive research on the nutritional profile and bioactive components of milk, there is no consensus on the presence or absence of milk-derived proteins or peptides in the blood post-consumption of milk or dairy products.
Many studies have identified milk-derived proteins or peptides from blood, but there is no existing catalog of all the proteins and peptides found from the blood matrix. Various types of study design exist, but they consider several types of animals, feed sources, and other variables. In addition, there is currently no existing catalog, or review, encompassing all milk-derived proteins and peptides found in blood, or the methods for identifying them from a blood matrix.
The objective of this article was to create a comprehensive list of milk-derived proteins and peptides detected in blood after digestion of milk or other dairy products.
A total of 108 studies were included, of which 102 detected milk-derived proteins or peptides in blood, mainly intact immunoglobulin G (IgG), β-lactoglobulin (BLG), α-lactalbumin (ALA), and casein peptides.
Overall, this review will inform researchers about (i) established milk-derived proteins and peptides that can be found in blood from consuming dairy, (ii) bioactive milk-derived peptides with potential to exert bioactivity systemically, and (iii) what methods are optimal for use in identifying absorbed proteins and peptides.

CDRF- Funded Research – Association of lactose intake and lactase persistence genotype with microbial taxa and function in healthy multi-ethnic U.S. adults. Tang Y, Oliver A, Alkan Z, Korf I, Huang L, Kable ME, Lemay DG. Food Funct. 2025 Aug 29.

Lactase persistence is a genetically inherited trait that enables continued lactose digestion into adulthood. Lactase non-persistence (LNP) individuals often experience incomplete lactose digestion, allowing undigested lactose to reach the colon, where it may shape microbial composition and function.
Researchers investigated the relationship between the lactase persistence (LP) genotype, lactose consumption, and the taxonomic and functional profiles of the fecal microbiome.
Participants from the USDA Nutritional Phenotyping Study, a cross-sectional observational study designed to assess how dietary factors impact human health, whose fecal microbiome profile was measured using shotgun metagenomic sequencing (n = 330) were included in this analysis.
The LP/LNP genotype was determined by a single nucleotide polymorphism (SNP ID: rs4988235). Several genera of lactic acid bacteria (Veillonella, Lactobacillus, Lacticaseibacillus, and Lactococcus) were differentially abundant between recent high-lactose consuming (>10.0 g lactose per day) and low-lactose consuming (<3.3 g lactose per day) individuals.
Among the LNP participants who self-identified as Caucasian or Hispanic, high-lactose consumers (>10.0 g per day via 24-h recall) had significantly higher relative abundances of lactic acid bacteria and lactate-utilizing bacteria (Lacticaseibacillus, Lactobacillus, Megamonas, and Veillonella) than low-lactose consumers (<3.3 g per day).
Independent of lactose intake, LNP participants had a higher abundance of fecal microbial β-galactosidase genes than LP participants. Among the LNP participants, those with high recent lactose consumption also showed a significant shift towards more fecal propionate.
The abundance of the yogurt-associated microbe, Streptococcus thermophilus, was positively associated with yogurt intake independent of the genotype. Alternative milk consumption was significantly negatively associated with fecal SCFAs both in the full cohort and the Caucasian/Hispanic subset, regardless of the genotype.
These results suggest that functional and persistent host lactase enzymes may work to competitively exclude lactic acid bacteria, contributing to a smaller realized niche for lactic acid bacteria in LP individuals compared to LNP individuals. However, regardless of the host genotype, consumption of alternative milk may be associated with reduced production of health-promoting intestinal metabolites, such as SCFAs.

Effects of IGF1 rs6214 Polymorphism and Milk Consumption on Serum Levels of IGF-1 and GH and Body Composition. Grijalva-Avila JC, Villanueva-Fierro I, Loera-Castañeda V, et al. Metabolites. 2025 Aug 20;15(8):556.

Milk and dairy are rich in insulin-like growth factor 1 (IGF-1), a protein secreted through the action of growth hormone (GH) and implicated in growth and metabolism.
This study aimed to investigate the roles of milk intake and body composition and identify the presence of the single nucleotide variant (SNV) rs6214 in the insulin-like growth factor 1 gene (IGF1) and its effects on the serum IGF-1 and GH levels and body composition.
Researchers analyzed 110 volunteers with and without a history of milk intake. Through a case-control study with one hundred ten healthy volunteers, serum IGF-1 and GH levels were measured using the ELISA technique, the body composition was determined with bio-electrical impedance equipment, genotyping of the rs6214 SNV was carried out using real-time PCR, and a dietary questionnaire was administered to assess milk intake, with or without consumption.
The results showed that the highest levels of IGF-1 were found in people who regularly consumed milk, along with a lower body mass index (BMI) and percentage of fat. A lower BMI and fat percentage were associated with higher levels of IGF-1, lean mass, and SNV presence. Lower levels of BMI and percentages of subcutaneous and visceral fat were found in regular milk consumers.
This study suggests that dairy intake and the IGF1 gene rs6214 SNV are associated with higher levels of IGF-1, high levels of lean mass, a low BMI, a low % fat, and low visceral fat.

Are all ultra-processed foods bad? A critical review of the NOVA classification system. Louie JCY. Proc Nutr Soc. 2025 Aug 4:1-9.

The NOVA food classification system and its categorization of ultra-processed foods (UPFs) have significantly influenced dietary guidelines worldwide, yet the assumption that all UPFs are uniformly harmful warrants critical examination.
Here, a review of evidence revealed substantial heterogeneity in health outcomes across UPF subtypes, with products like sugar-sweetened beverages consistently associated with adverse outcomes while fortified cereals and certain dairy products demonstrate neutral or protective effects.
The binary nature of NOVA’s classification fails to account for nutritional composition, fortification benefits, and cultural food traditions, creating inconsistencies in categorization across different contexts.
Methodological limitations in UPF research include inadequate dietary assessment tools, selective reporting of negative findings, and experimental design flaws that conflate processing with other dietary factors.
Implementation challenges extend to socioeconomic accessibility, as UPFs often provide cost-effective nutrients for disadvantaged populations and environmental sustainability, where wholesale reduction could increase resource demands.
Future directions should develop more nuanced classification systems that integrate processing methods with nutritional quality to better inform public health strategies rather than categorically rejecting all UPFs.

Innovation, Social Science, and Dairy Alternatives

Invited review: Development of a dairy barn concept to improve animal welfare. Wulf R, Demba S, Bachmann L, et al. J Dairy Sci. 2025 Aug 20:S0022-0302(25)00684-8.

Owing to political and societal requirements, farmers are required to produce animal-friendly and sustainable products in an economic manner. Investments have been made to improve housing conditions for farm animals such as cattle, but further improvements regarding animal welfare of dairy husbandry are needed to regain societal acceptance.
In this review, researchers first provide a brief overview of current housing and management conditions of dairy cattle worldwide as well as their impact on animal welfare of calves, young stock, and dairy cows.
This framework was the basis to develop a concept for an alternative demonstration and research barn, the “future dairy barn” (FDB). Crucial for this barn concept was the consideration of the natural behavior of all cattle belonging to a herd to improve animal welfare.
Consequently, the FDB concept integrated a family herd that avoids regrouping and enables stable social relationships, a free lying area to allow species-typical lying behavior and pasture or paddock access to enable the cattle to stay indoors or outdoors.
This alternative dairy barn concept should help answer research questions on animal welfare in a uniform social and physical environment in long-term investigations. The construction of the FDB aims to support the future of dairy farming.

INVITED REVIEW: Contribution of milk harvesting research to optimal interaction between biology and milking technology. Upton J, Bruckmaier RM, Rasmussen MD, et al. J Dairy Sci. 2025 Jul 31:S0022-0302(25)00596-X.

The broad focus of this review is on milk harvesting in machine-milked herds. With particular emphasis on: (1) milk secretion and storage dynamics in the udder, (2) milk ejection, (3) milk flow profiles and their effect on milking efficiency, (5) immunological activity and milking efficiency, (5) milking machine aspects of milk removal, and (6) the future potential of milking technology.
Machine milking has evolved from its early mechanical beginnings into a technologically advanced, data-driven process that must balance speed, chosen completeness, and gentleness on teat tissue to support efficient milk removal and optimal udder health.
This review summarizes the current understanding of milk harvesting from a physiological, mechanical, and managerial perspective and outlines the key factors shaping its future development.
Fundamentally, milk harvesting is built upon a biological sequence involving milk synthesis, ejection, and removal. Milk synthesis occurs at the alveolar level and is influenced by local quarter-specific physiology. Milk ejection is driven by the oxytocin-mediated contraction of myoepithelial cells, a process sensitive to the degree of udder filling, familiarity with the milking environment, and cow-operator interactions.
Milk flow profiles, shaped by these biological processes, provide crucial insights into milking efficiency and udder health outcomes. At the machine level, key variables include milking vacuum, pulsation characteristics, liner properties, and teatcup removal strategies. Optimal settings for each of these parameters depend on dynamic interactions with cow physiology and milking stage.
Recent research highlights the need to consider these factors not in isolation but as part of an integrated milking system, where vacuum, pulsation, liner design, and timing of teatcup removal interact to affect milking speed, teat condition, and udder health.
Automation of milking systems and indeed automated milking systems have driven a shift toward individualized milking at the quarter level, enabling more precise control of extraction timing and flow rate.
The integration of real-time sensor data, machine learning, and adaptive milking parameters represents a major step forward in the optimization of milking systems.
In the near future, distinctions between automated milking systems and conventional systems will become increasingly blurred, as both adopt automation and intelligent controls tailored to individual cows and quarters.
This review also explores the role of immunological activity in shaping milking efficiency. Elevated SCC has been associated with altered milk flow curves and decreased productivity.
There is emerging evidence suggesting that modern selection and management strategies may reduce the historical link between fast milking and mastitis risk. This relationship remains complex and context dependent. The detection and management of abnormal milk (supported by more advanced inline sensor systems) is expected to become a cornerstone of future milking technology.
Looking forward, the drivers of change in milk harvesting will include labor availability, economic pressures, environmental concerns, animal health, and consumer expectations. A new era of biologically aware, data-informed, and precision-engineered milking systems is emerging. These systems will support the gentle, efficient removal of milk to a user-defined end point, tailored to each animal and each milking event.

Computational Architectures for Precision Dairy Nutrition Digital Twins: A Technical Review and Implementation Framework. Rao S, Neethirajan S. Sensors (Basel). 2025 Aug 8;25(16):4899.

Sensor-enabled digital twins (DTs) are reshaping precision dairy nutrition by seamlessly integrating real-time barn telemetry with advanced biophysical simulations in the cloud. Drawing insights from 122 peer-reviewed studies spanning 2010-2025, this systematic review reveals how DT architectures for dairy cattle are conceptualized, validated, and deployed.
Researchers introduce a novel five-dimensional classification framework-spanning application domain, modeling paradigms, computational topology, validation protocols, and implementation maturity-to provide a coherent comparative lens across diverse DT implementations.
Hybrid edge-cloud architectures emerge as optimal solutions, with lightweight CNN-LSTM models embedded in collar or rumen-bolus microcontrollers achieving over 90% accuracy in recognizing feeding and rumination behaviors. Simultaneously, remote cloud systems harness mechanistic fermentation simulations and multi-objective genetic algorithms to optimize feed composition, minimize greenhouse gas emissions, and balance amino acid nutrition.
Field-tested prototypes indicate significant agronomic benefits, including 15-20% enhancements in feed conversion efficiency and water use reductions of up to 40%. Nevertheless, critical challenges remain: effectively fusing heterogeneous sensor data amid high barn noise, ensuring millisecond-level synchronization across unreliable rural networks, and rigorously verifying AI-generated nutritional recommendations across varying genotypes, lactation phases, and climates.
Overcoming these gaps necessitates integrating explainable AI with biologically grounded digestion models, federated learning protocols for data privacy, and standardized PRISMA-based validation approaches.
The distilled implementation roadmap offers actionable guidelines for sensor selection, middleware integration, and model lifecycle management, enabling proactive rather than reactive dairy management-an essential leap toward climate-smart, welfare-oriented, and economically resilient dairy farming.

An Intervention to Reduce Occupational Health Risk from Antibiotic Resistant Pathogens Among Dairy Farm Workers. Chao O, Shutske J, Young A, et al. J Agric Saf Health. 2025;31(1):31-45.

This study focused on developing and evaluating an educational intervention designed to mitigate occupational health risks associated with pathogens and antibiotic-resistant bacteria among dairy farm workers.
Data collected from farms and workers as part of a larger umbrella project that focused on dairy farm antibiotic use for cows and calves were used to inform elements of the Health Belief Model and the Theory of Planned Behavior, leading to eight intervention outcomes.
The intervention targeted increased knowledge and promoted behavioral changes related to worker and workplace hygiene best practices, PPE use, biosecurity, and personal antibiotic stewardship.
The intervention was conducted with 32 workers from five dairy farms, using pre- and post-intervention assessments to measure knowledge gains and behavioral intentions. Results demonstrated statistically significant increases in knowledge across all targeted outcomes, with most participants showing a high willingness and likelihood to implement recommended behaviors related to their workplace exposures and best practices. However, participants indicated a greater reluctance to change around issues of personal antibiotic stewardship.
Time constraints were the most significant and most consistent barrier to behavior change. The study highlights the importance of ongoing research and refinement of intervention strategies to address barriers and enhance protective practices among often underserved farmworkers in agriculture.
These intervention strategies contribute to improved occupational health outcomes with benefits to public health by reducing the spread of antibiotic-resistant infections to the broader population.

Metabolic profiling of bovine colostrum: unravelling the influences of diet and seasonality on functional dairy components. Pariyani R, Rocchetti G, O’Callaghan TF, et al. Food Chem. 2025 Aug 10;493(Pt 3):145900.

Bovine colostrum-based functional foods are gaining recognition for their potential beneficial roles in human health. However, while macronutrient variability has been extensively studied, the impact of seasonality and diet on bioactive metabolome profile of colostrum remains poorly understood.
This study employed UHPLC-HRMS to characterize the metabolic profile of colostrum from dairy cows, calving in autumn or spring under distinct environmental and dietary conditions.
An untargeted metabolomic analysis demonstrated distinct seasonal variations, with autumn-derived colostrum exhibiting a two-fold increase in 22 metabolites, including phospholipids, bioactive peptides, organic acids, and nucleotides.
Glycyl aspartate and D-erythro-imidazole-glycerol-phosphate emerged as key biomarkers distinguishing seasonality of colostrum. Pre-partum diet and environmental temperature were correlated with metabolic differences, whereas parity and genetic merit, represented by the economic breeding index, had minimal influence.
These findings highlight the impact of seasonality on the colostrum metabolome, providing novel insights for the future development of colostrum-based functional foods.

Digestion-Derived Nanoparticles from Dairy and Plant-Based Milks: Comparative Analysis of Cellular Uptake Kinetics and Intestinal Barrier Interactions. Liu X, Li S, Cao Y, et al. J Agric Food Chem. 2025 Aug 27;73(34):21550-21559.

The growing popularity of the plant-based milk alternatives highlights the need for a thorough evaluation of their colloidal properties, as variations in these properties may significantly influence their biological fate.
This study compares the physicochemical characteristics, cellular interactions, and intestinal barrier effects of nanoparticles (NPs) derived from digested cow’s milk and four commercial plant-based alternatives (almond, oat, soy, and coconut).
Cow’s milk NPs and plant-based NPs exhibited an average size ranging from 422 to 728 nm. The cellular uptake kinetics of these NPs demonstrated distinct patterns: rapid internalization for cow’s milk NPs, delayed uptake for almond/oat NPs, transient retention for soy NPs, and rapid initial uptake followed by swift clearance for coconut NPs.
Functional analysis further identified soy and oat NPs as optimal candidates for sustained nutrient delivery, while cow’s milk NPs favored rapid absorption. These insights aid in designing plant-based milks to tailor nutrient delivery profiles, safety and efficacy.

A Mixed-Method Assessment of Drivers and Barriers for Substituting Dairy with Plant-Based Alternatives by Danish Adults. Philippi Rosane B, Tjørring L, Wennerscheid S, et al. Foods. 2025 Aug 7;14(15):2755.

The market for plant-based alternatives to animal foods has increased rapidly in the past decade, mainly due to consumer demand. Little evidence is available regarding nutritional impacts, drivers, and barriers to using these products as substitutes for animal foods in real-life conditions.
Plant-based analogues to dairy (PBADs) are constantly compared to their animal counterparts, both regarding product characteristics, such as price and sensory properties, as well as cultural roles and subjective memories.
This pilot study followed 16 Danish adults (30 ± 11 years old; 11 females) for 4 weeks with substituting milk, cheese, and yogurt with PBADs and assessed their drivers and barriers to applying the intervention with a mixed-method approach.
The mixed methods showed dairy attachment, price, and taste were the main barriers to consuming PBAD, while changes in life and social circles were drivers (qualitative data).
As for the liking of PBADs, plant-based yoghurt was the preferred intervention product (73.5/100, p < 0.05), followed by plant-based drinks (65.9/100), while plant-based cheese was the lowest rated (47.9/100, p < 0.05).
As for dietary changes, a lower average intake of sugars, saturated fatty acids, cholesterol, calcium, phosphorus, and zinc was observed after the intervention.
Additionally, this study describes the attachment of the study population to milk and dairy products. It shows that choosing dairy is beyond nourishment but is connected to tradition, culture, pleasure, memories, and a sense of belonging. In contrast, there is no history or attachment to PBADs.