Dairy Research Bulletin: Selected Articles from June 2025 - California Dairy Research Foundation

Environmental Management and Sustainability

Biogenic and fossil main greenhouse gas emissions of dairy, beef, pig and poultry systems. Berton M, Sturaro E, Schiavon S, Bittante G, Cecchinato A, Xiccato G, Gallo L. Animal. 2025. 29;19(7):101562.

Conventional analyses of the carbon footprint of livestock systems do not consider the relationships between the characteristics and sources of each greenhouse gas (GHGs; CH₄, N₂O, CO₂) and the different livestock systems.
This study aimed to assess the carbon footprint of a variety of livestock systems, including different animal categories (dairy cattle, beef cattle, pig and poultry) and production circumstances (lowland and mountain areas).
An attributional cradle-to-gate-of-the-farm Life Cycle Assessment was used, considering the emission pattern of each GHG and distinguishing fossil and biogenic origins. The production stages included animal and manure management, on- and off-farm feed production and the production and use of the farm materials.
The functional unit was 1 kg of crude protein in animal food (CPAF). Emissions per single GHG and production stage were analysed with a general linear model which included the effect of the livestock system, which proved to significantly influence the emission pattern of all GHGs, both in absolute terms (kg/kg CPAF) and with respect to the single production stage.
The CO₂(fossil-based) resulted as the most emitted GHG (10.2-27.6 kg/kg CPAF), 10-255 and 284-646 times greater than CH₄ and N₂O, respectively.
Methane was found to be more associated with the animal category (ruminants), whereas N₂O and CO₂were more associated with the input intensity level.
Livestock systems strongly influenced the biogenic GHG emissions but not the fossil-related one, with dairy, pig and poultry systems showing similar and lower values than beef.
In conclusion, the evaluation of the pattern of each GHG as well as of their biogenic or fossil origin can give indications to address the reduction of global warming.

Considering greenhouse gas emissions from feed production in diet formulation for dairy cows as a means of reducing the carbon footprint. Managos M, Lindahl C, Agenäs S, Sonesson U, Lindberg M. Animal. 2025;19(7):101544.

Dairy production often faces conflicting goals, such as reducing greenhouse gas emissions, increasing food production and achieving self-sufficiency without transgressing planetary boundaries.
This study examined ways to decrease emissions intensity per kg of milk from high-producing cows by selecting feed ingredients with a low carbon footprint while also considering local alternatives.
Diets comprising of grass-legume mixture silage and three concentrate mixtures (standard commercial, based on by-products, and domestic crops grown on-farm) were randomly allotted to three groups of high-producing Swedish Holstein cows (N = 48).
Over 7 weeks, no differences were observed (mean ± SEM) in feed DM intake (commercial: 24.3, by-products: 24.7, domestic: 24.2 kg/day, ± 0.51 kg/day), energy-corrected milk (ECM) yield (commercial: 38.3, by-products: 38.5, domestic: 37.8, ± 0.98 kg/day) or enteric methane production (commercial: 387, by-products: 378, domestic: 402 g/day, ± 17.3 g/day) among the diets.
However, an evaluation of the primary carbon footprint of feed production (excluding transportation emissions) showed that the by-products and domestic diets gave lower emissions than the commercial diet, 9.4, 10.2, and 11.9 Feed CO₂equivalents (CO_2-eq) kg/day, respectively (SEM: ± 0.38 Feed CO_2-eq kg/day).
The emission intensity, expressed as feed emissions per kilogram of ECM yield, showed that the by-product-based and domestic diets generated lower carbon footprints, with emissions of 254 and 284 g Feed CO_2-eq/kg ECM, respectively, in comparison to 320 g Feed CO_2-eq/kg ECM observed for the commercial diet (SEM: ± 10.7 g Feed CO_2-eq/kg ECM).
Considering greenhouse gas emissions from feed production in diet formulation resulted in a lower overall feed carbon footprint and lower emission intensity per ECM. These findings can assist in formulating dairy rations for high-yielding dairy cows that balance conflicting goals while maintaining productivity.

Effect of a tannin and saponin blend feed additive on greenhouse gas and ammonia emissions from lactating dairy cows. Carrazco AV, Rocha AS, Ross EG, Zhao Y, Pan Y, Pandey PK, Castillo AR, DePeters EJ, Mitloehner FM. J Dairy Sci. 2025:S0022-0302(25)00381-9.

Animal agriculture accounted for over one-third of methane (CH₄) emissions in the United States in 2022; ~27% stemming from enteric fermentation and the remaining 9% from manure management practices. Beyond contributing to CH₄emissions, dairy cattle manure emits nitrous oxide (N₂O) when applied to land. This N₂O release results from processes in the nitrogen (N) cycle, such as nitrification and denitrification, carried out by soil microorganisms.
The objective of this study was to determine if a commercial feed additive blend composed of quebracho, chestnut tannins, and saponins (TAN; Silvafeed BX) could reduce enteric GHG and ammonia (NH₃) emissions without negatively effecting the productive performance of dairy cows.
Twenty mid lactation Holstein dairy cows were blocked by DIM and parity in a randomized complete block design, and were assigned to 1 of 2 treatments: TAN (n = 10) or control with no TAN (CON; n = 10). The treatments were administered as a top dress at each of 2 daily feedings with TAN supplemented at a rate of 0.07% of dietary DM.
Cow blocks were sampled for enteric gaseous emissions in head chambers (HC) for a 12 h period on their respective treatment d 0, 16, 32, and 48. After the enteric emission sampling period concluded, collected urine and manure were combined into a manure slurry at 1:1.7 (urine wt:feces wt) per cow.
Manure slurry methane (CH₄), carbon dioxide (CO₂), nitrous oxide (N₂O), and NH₃emissions were measured for 24 h. Supplemental TAN decreased enteric production (g/HC period or mg/HC period gas) of CH₄, CO₂, and N₂O over the trial period, and tended to increase NH₃ production in TAN-supplemented cows.
Gaseous emission yield (g or mg gas/kg HC DM intake) did not differ between TAN- and CON-supplemented cows for CH₄, CO_2,or N₂O, although TAN-supplemented cows had greater NH₃ Methane, CO₂, N₂O, and NH₃ intensity (g or mg gas/kg PM ECM) were not affected by TAN supplementation.
Supplemental TAN did not effect slurry GHG emissions, although it increased NH₃ No differences in ECM, milk fat yield, milk protein yield, and DMI in TAN-supplemented cows versus CON-supplemented cows were noted.

Limited effects of tannin supplementation on the dairy cattle fecal microbiome with modulation of metabolites. Klein ML, Erikson CB, McCabe CJ, Huang L, Rodrigues JLM, Mitloehner FM. Front Microbiol. 2025 Jun 10;16:1570127.

Tannins are plant secondary metabolites that bind organic carbon (C) and nitrogen (N), potentially altering substrate bioavailability for enteric fermentation in ruminants. This interaction may reduce greenhouse gas (GHG) emissions and influence nitrogen partitioning.
Given tannins’ resistance to ruminal degradation and persistence through the gastrointestinal tract, this study investigated the effects of a tannin-based feed additive on fecal microbial diversity, fecal chemical composition, and GHG emissions.
Twenty-four early- to mid-lactation dairy cows were randomized to receive either a tannin-based feed additive (TRT; containing condensed and hydrolyzable tannins from Schinopsis quebracho-colorado[Schltdl.]) or a control diet (CON) for 64 days.
Cows were blocked by parity, dry matter intake, milk yield, body weight, and days in milk. Fecal samples were collected on days 0, 16, 32, and 64 and analyzed using 16S rRNA gene amplicon sequencing. Fecal C, N, and indole-3-lactate were measured, and GHG emissions (N₂O, CH₄, CO₂) were assessed via 14-day laboratory incubation.
A total of 1,538 amplicon sequence variants were identified, with Firmicutes as the dominant phylum. Fecal phylogenetic diversity showed a significant treatment × day interaction (p< 0.01), with TRT cows exhibiting reduced microbial diversity from day 16 to 64. Fecal C and N concentrations were significantly lower (p < 0.01) in TRT cows on day 16, while indole-3-lactate levels were higher on day 64 (p = 0.02).
GHG emissions did not differ significantly between treatments. The tannin-based feed additive influenced fecal microbial community structure and select chemical parameters but did not significantly affect GHG emissions from feces.
These findings suggest that dietary tannins may modulate gut microbial ecology with minimal impact on downstream manure-related emissions.

Leveraging gene editing to combat methane emissions in ruminant agriculture. Zhao Y, Tan J, Fang L, Jiang L. Trends Biotechnol. 2025 Jun 14:S0167-7799(25)00206-9.

Methane emissions from ruminants represent a major contributor to global greenhouse gases (GHGs), posing challenges for sustainable agriculture and climate change mitigation.
Recent advances in clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated proteins (Cas)-based gene editing offer transformative approaches to address this issue by targeting both forage crops and rumen methanogens.
Enhancing lipid content and secondary metabolites in forage crops can suppress methanogenesis and improve feed efficiency, while precise genome editing in methanogenic Archaea can disrupt pathways critical to methane production. However, challenges remain regarding delivery methods, gene targeting specificity, ecological impacts, and regulatory acceptance.
In this review, we explore current progress, identify key knowledge gaps, and highlight the need for interdisciplinary strategies that integrate biotechnology, synthetic biology, and regulatory frameworks to develop effective and scalable methane mitigation solutions.

Animal Health and Food Safety

Controlling bird flu is urgent-for dairy, wildlife, poultry, pets, and people. Lowen AC, Bowman AS, Webby RJ, et al. J Am Vet Med Assoc. 2025 Jun 25:1-4.

Highly pathogenic avian influenza viruses of the H5N1 subtype have recently undergone a major geographic expansion. At the same time, these viruses have substantially broadened their host range.
Typically, H5N1 circulates in poultry, waterfowl, and shorebirds, but the breadth of avian species affected has increased and spillover to mammals has become common. The recent changes in H5N1 ecology have brought die-offs in wild birds and marine mammals, a sustained outbreak in US dairy cattle, and recurring spillover into domestic cats.
Maintenance of H5N1 in wild birds in North America has furthermore produced a persistent risk to US poultry.
Circulation of H5N1 in domestic animals has resulted in human infections, especially among farm workers and veterinarians, events that heighten the potential for a pandemic.
Through their central position in One Health, veterinarians have a critical role to play in mitigating the impact of H5N1 on animal health, agriculture, and public health.

Selective Dry Cow Therapy in Modern Dairy Management: Balancing Udder Health and Antimicrobial Stewardship. Ut ID, Berean DI, Bogdan LM, Ciupe S, Gog Bogdan S. Vet Sci. 2025 Jun 12;12(6):580.

In recent decades, Blanket Dry Cow Therapy (BDCT) has been regarded as a cornerstone strategy for the control of mastitis in dairy cows during the dry period. However, concerns regarding the rising incidence of antibiotic resistance and the associated zoonotic risks have prompted a paradigm shift, leading to intensified research into alternative management approaches.
In response, many countries have adopted a more targeted approach, known as Selective Dry Cow Therapy (SDCT), which focuses on the therapeutic use of antibiotics, administered only to cows or quarters that are either infected or at high risk of infection during the dry period.
This review provides a comprehensive synthesis of the scientific literature regarding the main methods for selecting animals for SDCT, the impact of this strategy on udder health, milk production, farm economics, and antibiotic consumption, as well as the factors that may influence its effectiveness.
Over time, a range of methods have been developed to identify infected animals, including bacteriological culture, somatic cell count (SCC), differential somatic cell count (DSCC), and the California Mastitis Test (CMT), which are often used alone or in combination with clinical mastitis history and/or parity.
Among these methods, SCC has proven to be the most economically viable and best suited for practical use, while its combination with DSCC has been shown to significantly enhance diagnostic accuracy. According to the studies reviewed, SDCT is a safe and effective strategy for maintaining udder health and farm profitability, as long as infected cows are accurately identified, and internal teat sealants are used in quarters not treated with antibiotics during the dry period.
However, since udder health is influenced by herd characteristics, management practices, and regional pathogens, the findings cannot be universally applied and must be adapted to each herd’s specific conditions.

Assessing the Impacts of Dairy Farm Antimicrobial Use on the Bovine Fecal Microbiome. Steinberger AJ, de Campos JL, Suen G, et al. Animals (Basel). 2025 Jun 12;15(12):1735.

Rising rates of antimicrobial-resistant infections have prompted increased scrutiny on antimicrobial use (AMU) in livestock agriculture. Dairy farms primarily use antimicrobials to maintain animal health and welfare by treating and preventing infectious diseases. However, the impact of dairy farm AMU practices on the cattle fecal microbiome remains largely unclear, partly due to difficulties in quantifying AMU.
This study leveraged quantitative AMU data from 40 large commercial dairy farms to identify farms with low (n = 4) and high (n = 4) AMU.
Using 16S rRNA gene amplicon sequencing, researchers compared the fecal bacterial communities of dairy calves and cows (healthy, cull, sick) by both AMU designation (high/low) and by individual farm AMU, summarized by animal defined daily dose (DDD) and mg/kg.
The researchers found significant differences in beta-diversity between cattle from high- and low-AMU groups using either method and found that Corynebacterium and Clostridium abundances increased with farm AMU. Additionally, they found fecal bacterial communities differed across farms within high- and low-AMU groupings, highlighting the need to account for farm-to-farm variation when assessing AMU impacts.
These findings suggest that dairy farm AMU influences the fecal microbiome and identifies specific taxa that warrant further investigation as potential reservoirs for antimicrobial resistance genes.

Bovine Subclinical Mastitis Foodborne Pathogens: Risks and Mitigation of Microbial Safety of Raw Milk and Dairy Products. Della D, Tiwari U, Duffy G, Boloña PS, Fenelon M, O’Brien T. Foodborne Pathog Dis. 2025 Jun 26.

Bovine subclinical mastitis (SCM), unlike clinical mastitis, characterized by the absence of visible symptoms such as swelling and abnormal milk, represents an under-recognized challenge for microbial safety within the dairy industry. Because SCM lacks visible signs, it can serve as a silent source of contamination that is not easily identified or managed during milk production.
The review critically examines the multifaceted interplay between SCM and the transmission of such pathogens in milk, highlighting their entry routes, detection modalities, and contributory risk factors to the dairy industry, considering global and regional variability, the prevalence, diversity, and emerging trends in milk-borne pathogens are considered.
To address these challenges, an integrative One Health-aligned mitigation framework that combines microbial risk assessment, genomic surveillance, and data-driven risk prioritization is recommended.
Such strategies aim to harmonize detection protocols, optimize antimicrobial stewardship, and strengthen control measures across dairy value chains. By synthesizing current knowledge, this review article underscores the importance of SCM as a food safety issue and offers a critical foundation for developing comprehensive strategies to mitigate public health risks.

Effects of probiotic supplementation on growth performance and feed intake of dairy calves: A meta-analysis. Branco-Lopes R, Winder C, Canozzi ME, Lopez YSA, Schmitz B, Silva-Del-Río N. J Dairy Sci. 2025 Jun 11:S0022-0302(25)00425-4.

The growth performance of dairy calves influences their future reproductive and productive performance as parous cows. Age at first calving and milk yield of primiparous cows have been associated with calf growth rate during both preweaning and postweaning periods.
The objective of this systematic review and meta-analysis was to evaluate the effect of probiotic supplementation on ADG, feed intake, and feed efficiency (FE) of dairy calves. A secondary objective was to assess outcomes stratified by probiotic type.
55 studies were included in the analysis. Multilevel random-effects models were fitted for a single dataset combining all trials regardless of probiotic type and for 4 datasets stratified by 4 probiotic types (Bacillus, Lactobacillus, Saccharomyces, and multiple genera probiotics).
Meta-analyses showed that probiotic supplementation did not result in significant difference in FE compared with the control group (no treatment or placebo). Probiotic supplementation improved total DMI, starter intake, and ADG and tended to decrease milk intake.
A meta-regression analysis indicated a significant association between starter intake and probiotic type and the duration of probiotic supplementation.
Analyses by probiotic type revealed no significant effects on DMI or FE for Lactobacillus spp., Saccharomyces spp., or multiple genera probiotics, whereas Bacillus spp. showed no effect on DMI but a tendency to improve FE.
Supplementation with Lactobacillus spp. and multiple genera probiotics tended to increase starter intake. Supplementation with Bacillus spp. and Lactobacillus spp. increased the ADG of calves, whereas Saccharomyces spp. and multiple genera probiotic supplementation did not yield significant differences.
Substantial and significant heterogeneity was observed for most outcomes; thus, results must be interpreted carefully. Probiotics may be beneficial for enhancing DMI, starter intake, and ADG in dairy calves; however, current evidence remains limited due to high heterogeneity.
Results of analyses by probiotic type should be interpreted carefully due to the limited number of studies per category. To develop appropriate recommendations, additional research is required to address the sources of heterogeneity in existing studies.

Heat Stress from Calving to Mating: Mechanisms and Impact on Cattle Fertility. Capela L, Leites I, Pereira RMLN. Animals (Basel). 2025 Jun 13;15(12):1747.

Animal production is a core sector to solve the increasing food demand worldwide, with productivity severely affected by climate change. Experts are predicting huge global productive losses in animal-derived products. Moreover, productive loss affects the economy, and the US dairy industry has reported losses of 1.5 billion dollars annually due to climate change.
Beef and dairy production are based on cow reproduction and fertility is a key indicator of productivity. However, under heat stress (HS), several physiological modifications decrease cows’ fertility.
Lower levels of estradiol, progesterone, and epidermal growth factor lead to undetectable ovulations, an inability to maintain the embryo and the pregnancy, or increased cortisol levels, inducing immunosuppression and, consequently, puerperal diseases delaying new pregnancies.
The welfare of cows under HS, especially those raised on pasture, is a huge concern. Considering the impact of ambient-temperature-induced HS, developing strategies to improve fertility-namely through the selection of thermotolerant breeds allied to environmental management measures-can improve cattle production efficiency and reduce resource use, thereby reducing the carbon footprint.
This review focuses on the effects of HS on female fertility, from parturition until the new conception, and on the role of heat shock proteins during this period.

A systematic review and meta-analysis of physical environmental enrichment to improve animal welfare-related outcomes in indoor cattle. Unsal G, Johnson KF, Stergiadis S, Bennett R, Barker ZE. Anim Welf. 2025 Jun 13;34:e37.

This systematic review aims to evaluate the effectiveness of various physical environmental enrichment items such as brushes, ropes, teats, chains, balls, cowhides/blocks, at improving the welfare of indoor-housed calves, heifers, and cattle.
This review of 33 peer-reviewed papers and one industry report evaluated different welfare-related outcomes following physical environmental enrichment, including feed intake, lying time, play and exploratory behaviour, aggression, stereotypic behaviour and cross-sucking behaviour.
The results of the meta-analysis revealed that calves and heifers enrolled in experimental studies using enrichment items had significantly improved growth rates, and increased locomotor play, but the overall reduction in cross-sucking behaviour was small and non-significant.
The effect of enrichment on feed intake, aggression/stereotypic behaviour, play behaviour, cleanliness score contrasted between studies, with some reporting improvements while others showed no effect of environmental enrichment in these parameters.
Overall, this review underscores the significant positive impact of physical enrichment on the welfare and behaviour of indoor-housed cattle, while highlighting the need for further research to optimise enrichment strategies across different cattle age groups and housing conditions.

Comparison of milk production and endocrine profiles of dairy cows exposed to either white light-emitting diode or induction lighting. Inabu Y, Takakura Y, Sugino T, et al. Domest Anim Endocrinol. 2025 Jun 8;93:106958.

White light-emitting diodes (WLEDs) are characterized by their high blue light intensity, whereas induction lighting (IL) emits lower levels of blue light.
This study investigated the effects of exposure to WLED and IL on milk production and physiological responses in dairy cows.
Nine lactating Holstein cows [225 ± 32.5 days in milk, 710 ± 24.6 kg initial body weight (BW), 2.6 ± 1.6 parity] were kept under a 16:8 h light-dark cycle and assigned to two treatments for 3 wk each in a 2 × 2 crossover design: exposure to either WLED (443 nm peak wavelength, 231 lx) or IL (529 nm peak wavelength, 237 lx).
During the dark period, light intensity was 0.0 lx. All cows were fed total mixed ration ad libitum. Milk samples were collected weekly, and serial blood sampling was performed on the last day of each treatment.
Dry matter intake, BW, milk yield, and milk composition did not differ between treatments. However, plasma non-esterified fatty acids concentration tended to be higher for the WLED than for the IL.
In addition, plasma melatonin and cortisol concentrations were higher for the WLED group than for the IL group.
These findings suggest that differences in light wavelength between WLED and IL affect melatonin and cortisol secretion and may also impact lipid metabolism, without altering milk production performance.

Nutrition and Health

Fermented Dairy Products as Precision Modulators of Gut Microbiota and Host Health: Mechanistic Insights, Clinical Evidence, and Future Directions. Gao Y, Liu Y, Mu G, et al. Foods. 2025. 29;14(11):1946.

Dairy products-encompassing yogurt, kefir, cheese, and cultured milk beverages-are emerging as versatile, food-based modulators of gut microbiota and host physiology.
This review synthesizes mechanistic insights demonstrating how live starter cultures and their fermentation-derived metabolites (short-chain fatty acids, bioactive peptides, and exopolysaccharides) act synergistically to enhance microbial diversity, reinforce epithelial barrier integrity via upregulation of tight-junction proteins, and modulate immune signaling.
Clinical evidence supports significant improvements in metabolic parameters (fasting glucose, lipid profiles, blood pressure) and reductions in systemic inflammation across metabolic syndrome, hypertension, and IBS cohorts.
Herein, researchers highlight critical modulatory factors-including strain specificity, host enterotypes and FUT2 genotype, fermentation parameters, and matrix composition-that govern probiotic engraftment, postbiotic yield, and therapeutic efficacy.
Despite promising short-term outcomes, current studies are limited by heterogeneous designs and brief intervention periods, underscoring the need for long-term, adaptive trials and integrative multi-omics to establish durability and causality.
Looking forward, precision nutrition frameworks that harness baseline microbiota profiling, host genetics, and data-driven fermentation design will enable bespoke fermented dairy formulations, transforming these traditional foods into next-generation functional matrices for targeted prevention and management of metabolic, inflammatory, and neuroimmune disorders.

Full-fat yogurt compared with non-fat yogurt reduces blood triacylglycerol concentrations and lowers the triacylglycerol content in specific lipoprotein subclasses in adults with prediabetes: an exploratory analysis of a randomized-controlled trial. Taormina VM, Eisenhardt S, Gilbert MP, Poynter ME, Kien CL, Kraft J. Lipids Health Dis. 2025 Jun 5;24(1):201.

Low- and non-fat dairy foods have long been recommended over full-fat dairy foods due to the negative effect of saturated fatty acids on blood lipids. Recent research, however, suggests saturated fatty acids from dairy foods may not impart these negative health effects.
The objective of this study was to evaluate changes in blood lipids following a diet with full-fat (3.25%) yogurt compared with a diet with non-fat yogurt.
A randomized, double-masked crossover controlled-feeding trial was performed. Participants with prediabetes (n = 13, 7 female and 6 male participants) consumed three daily servings of full-fat or non-fat yogurt for the three weeks of each experimental diet.
A one-week run-in diet preceded each experimental diet period. After each experimental diet period and the first run-in diet period, fasting blood and blood drawn at four post-prandial time points during a mixed meal tolerance test were analyzed for lipoprotein concentrations and contents (i.e., the lipid fractions within the lipoproteins).
Fasting blood triacylglycerol concentrations were 10% lower in response to the full-fat yogurt diet, compared with the non-fat yogurt diet. While no diet-induced differences were observed in lipoprotein subclass concentrations, the triacylglycerol contents of smaller very low-density, intermediate-density, and low-density lipoproteins were lower in response to the full-fat yogurt diet.
Trends indicated potentially greater high-density lipoprotein cholesterol concentrations and high-density lipoprotein size following the full-fat yogurt diet. The ratio of triacylglycerols: high-density lipoprotein cholesterol concentrations was 17% lower following the full-fat yogurt diet.
In conclusion, this exploratory analysis demonstrates that short-term full-fat yogurt consumption elicits beneficial effects on the blood lipid profile in individuals with prediabetes and highlights the need for further evaluation of the contribution of dairy fat in yogurt and other dairy food matrices in lipid homeostasis and metabolic health.

Maternal intake of dietary protein from plant and animal sources and development of pharmacologically treated hypertension within 10 years after pregnancy. Øyen J, Brantsæter AL, Egeland GM, et al. Eur J Prev Cardiol. 2025 Jun 13:zwaf343.

The relationship between dietary protein intake and hypertension remains unclear, especially regarding protein from different sources such as plants and animal sources.
To investigate associations between intake of protein from plant and animal sources and risk of development of pharmacologically treated hypertension in a large population of Norwegian mothers followed up to 10 years after delivery.
Women in the Norwegian Mother, Father and Child Cohort Study (MoBa) recruited between 2004-2008 were linked to the Norwegian Prescription Database (2004-2013) to ascertain antihypertensive medication usage.
Women with hypertension before pregnancy were excluded, leaving 59,967 mothers for analyses. Diet was assessed by a validated semiquantitative food frequency questionnaire in mid-pregnancy.
A total of 1,480 (2.5%) women developed hypertension within 10 years of follow-up. Intake of protein from dairy, particularly milk/yoghurt, was inversely associated with hypertension (HR for highest vs. lowest milk/yoghurt quintile: 0.76). Intake of red meat protein was positively associated with hypertension (HR for quintile four vs. quintile one: 1.27). No significant associations were observed for plant-based protein sources.
The findings suggest that intake of protein from dairy sources is inversely associated with hypertension, while protein from red meat is positively associated with developing hypertension up to ten years after pregnancy.
This study provides novel contributions to the literature by examining the impact of a diverse array of plant and animal protein sources on the risk of hypertension in women.

Association Between Dietary Protein Sources and Nutrient Intake in the Diet of Canadian Children. Fabek H, Salamat S, Anderson GH. Nutrients. 2025;17(11):1834.

Canada’s 2019 Food Guide (CFG) encourages the increased consumption of plant-based foods as dietary protein sources. However, the nutritional implications of replacing animal-based proteins with plant-based alternatives in children’s diets remain unclear.
This study aimed to examine the association between protein food sources and nutrient intake in Canadian children aged 9-18 years.
Researchers analyzed data from 2324 children from the 2015 Canadian Community Health Survey (CCHS), using the Public-Use Microdata File (PUMF) containing 24 h dietary recalls.
Participants were categorized into four groups based on the proportion of protein from plant sources: Group 1 (0-24.9%), Group 2 (25-49.9%), Group 3 (50-74.9%), and Group 4 (75-100%). Nutrient intakes were compared and assessed against the Recommended Dietary Allowances (RDAs) and Adequate Intake (AI).
The results showed that a 3:1 animal-to-plant protein ratio (Group 2) aligned most closely with dietary recommendations. Groups 1 and 2 exceeded RDAs for protein, iron, vitamin B12, thiamine, riboflavin, niacin, vitamin B6, and zinc by over 146% (about four SDs above the mean requirement), suggesting a low risk of inadequacy, although saturated fat intake was high.
The intakes of vitamin D and folate were below 66% of the RDA, while calcium and magnesium were below 100% in some subgroups, with probabilities of inadequacy of 0.93 and 0.31, respectively. Group 4 (2.71%) was too small for reliable analysis.
In conclusion, an approximate 3:1 ratio of animal-to-plant protein sources may represent an optimal balance for supporting nutrient intake and improving macronutrient profiles in the diets of Canadian children.

Long-term consumption of liquid dairy products predicts lower fracture risk in aging women: a 25-year follow-up. Alaghehband FR, Lyytinen AT, Rikkonen T, et al. Eur J Nutr. 2025 Jun 9;64(5):213.

Globally, fracture is a major public health issue causing pain, disabilities, loss of independence, diminished quality of life and premature mortality among older adults. Over the past 3 decades, the fracture incidence has increased by 33.4% worldwide, mainly due to the aging of the population.
Fractures in older adults are the most common clinical manifestation of osteoporosis. Worldwide, 9 million osteoporotic fractures happen annually which equates to one osteoporotic fracture every 3 seconds.
The study aimed to investigate whether high dairy products consumption is associated with reduced fracture risk in aging women, contributing to understanding this health issue.
Data was obtained from the Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE) study, a large cohort of 14,220 older Finnish women (mean baseline age 52.3 years) with 25 years of follow-up.
Participants completed questionnaires every five years, providing information on health status, lifestyle habits, dairy products consumption (milk, sour milk, yogurt, cheese), and fracture history.
The models were adjusted for time-updated BMI (kg/m²), alcohol use (portions/day), physical activity (hours/month), age (years), use of calcium and/or vitamin D supplements (yes/no), and use of bone-affecting medications (yes/no).
Higher liquid dairy products consumption (milk, sour milk, yogurt) was associated with decreased risk for any fracture (P = 0.008) and osteoporotic fracture (P = 0.011). In contrast, cheese consumption was not associated with the overall risk of any fracture or osteoporotic fracture. In a separate analysis, higher cheese consumption was linked to a reduced hip fracture risk (P = 0.043) while no association was found between liquid dairy products consumption and hip fracture risk.
In conclusion, a long-term consumption of liquid dairy products may lower fracture risk. Encouraging the consumption of these products through public health initiatives may help reduce fractures and ease the economic burden on the healthcare system.

Lactase-Treated A2 Milk as a Feasible Conventional Milk Alternative: Results of a Randomized Controlled Crossover Trial to Assess Tolerance, Gastrointestinal Distress, and Preference for Milks Varying in Casein Types and Lactose Content. Robinson LA, Cavanah AM, Frugé AD, et al. Nutrients. 2025 Jun 6;17(12):1946.

Previous research indicates that gastrointestinal discomfort from milk consumption may be attributable to A1 β-casein, rather than lactose intolerance alone. A2 milk (free of A1 β-casein) consumption may result in fewer symptoms compared to conventional milk containing both A1/A2 β-casein.
In this five-week, double-blind, double-crossover study, researchers assessed the physiological responses to doses escalating in volume of lactose-free conventional milk (Lactaid), A2 milk, and lactose-free A2 milk in fluid milk-avoiding participants.
Each milk type was consumed over three separate weeks with three increasing doses across five days per week, >one week washout. Gastrointestinal symptoms, blood glucose, and breath gases were monitored for twenty-four, two-, and three-hours post-consumption, respectively. Sensory evaluation was completed for each sample.
Fifty-three participants consented and were randomized, with forty-eight participants completing the study.
Overall, symptoms were minimal. On Days 1 and 3, lower ratings of bloating and flatulence were observed in A2 compared to lactose-free A2. Breath hydrogen responses reflected lactose content, but were higher in lactose-free A2 than Lactaid on Day 5.
Thirty-three participants were deemed lactose-intolerant and had higher fasting and average breath hydrogen for all samples. The only symptom corresponding to the increase in breath hydrogen among these participants was flatulence after A2 consumption.
Surprisingly, flatulence was apparently higher for lactose-tolerant individuals when consuming Lactaid compared to A2. Conclusions:
These findings suggest that adults who avoid conventional fluid milk consumption may experience minimal GI discomfort from lactose-free and/or A1-free milks.

The impact of pasture-fed vs total mixed ration derived whole milk powder (WMP) on circulating fatty acid concentrations and cardiometabolic health in healthy adults: results from a randomised controlled crossover trial. Rooney M, O’Connor A, Feeney EL, Gibney ER, et al. J Nutr Biochem. 2025 Jun 12:110004.

Whole milk powder (WMP) produced from pasture-fed dairy herds has been shown to have increased concentrations of unsaturated fatty acids (FA), including, but not limited to, ALA (C18:3 n-3) and oleic acid (C18:1 cis-9), compared to WMP derived from indoor herds consuming total mixed ration (TMR).
Dairy products have been shown to have neutral or beneficial effects on cardiometabolic health, however, evidence on WMP in this area is lacking. Given the global market for WMP as a food ingredient, an investigation into the effect of TMR vs pasture -fed WMP on human health is warranted.
To test the effect of WMP derived from TMR and pasture-fed herds on circulating FA concentrations and other markers of cardiometabolic health in adults.
Healthy subjects were randomised to receive up to 200g WMP/day as part of a 6-week crossover trial, with a 4-week washout period. WMP was produced from milks of TMR and pasture-fed cows. WMP were isocaloric and macro-nutrient matched. The primary outcome was differences in circulating FA between weeks 0-6 changes in cholesterol concentrations, glycaemic control, blood pressure, anthropometry were secondary outcomes. Dietary intake was also analysed.
A total of n 29 participants, 58.6% male, with a mean ± SE age of 39.8 ± 2.3 years and BMI of 26.12 ± 1.39 kg/m²completed the study protocol. No time × treatment interactions were observed for cholesterol concentrations, markers of glycaemic control, blood pressure or anthropometry.
There was no time × treatment interaction for classes of FA, however, the very long-chain saturated FA, lignoceric acid (C24:0), decreased in response to pasture-fed WMP consumption (-0.05 ± 0.04 %TFA) with no change observed in response to the TMR WMP consumption (0.00 ± 0.04 %TFA, P=0.041).
Overall, chronic, high-dose consumption of TMR and pasture-fed WMP had no effect on cardiometabolic health in healthy adults, despite different fatty acid composition. Comparison of foods with a proven dairy matrix effect, e.g., cheese made from TMR and pasture-fed milks, may have more promising effects on human health.

Innovation, Social Science, and Dairy Alternatives

Does the use of Beef-on-Dairy lead to increased longevity in dairy herds? Hüneke L, Schmidtmann C, Rensing S, Thaller G, Heise J. Animal. 2025 Jun 9;19(7):101571.

The genetic progress of longevity in Holsteins has been very strong over the last years; however, the phenotypic longevity only increases moderately. It is often argued that this discrepancy between genetic and phenotypic longevity can mainly be explained with the availability of too many replacement heifers on the farms.
Following this hypothesis, a farmer would rather prematurely cull a cow from the herd than the freshly calved heifer. The availability of dairy replacements on the other side depends on other management decisions: rate of born female dairy calves, rate of losses, sales and purchases of female dairy calves.
The rate of born female dairy calves is influenced largely by (a) the use of sexed semen and (b) the use of beef semen on dairy cows (BoD). In our study, we analysed, whether herds with a lower rate of born female dairy calves (and therefore less available replacement heifers) have higher average longevity of cows.
The data set comprised 2,784,880 calving records and 1,025,203 disposals, resulting in data of 10,627 German herds. These herds were clustered into groups based on (1) the proportion of BoD use and (2) the proportion of female dairy calves born in 2020/2021. The average longevity of cows culled in 2022/2023 (replaced by calves born in 2020/2021) was compared.
The genetic level (Estimated breeding value of longevity) did not differ significantly between the categories of farms nor did the average production level (milk yield) per herd. A significant association was found between BoD use and phenotypic longevity: herds with high BoD use (> 20%) had an average longevity that was 147 days longer than that of herds with no BoD use (< 2%).
Similarly, herds with a lower proportion of female dairy calves born had a significantly higher average longevity: herds with > 55% female dairy calves (thus, a high number of possible replacement heifers) had an average longevity of 1,197 days, whereas herds with < 40% female dairy calves had an average longevity of 1,335 days.
This strong increase in average longevity related to the reduction of possible replacements indicates that many cows are culled early due to management decisions rather than due to health issues and other functional reasons.

Metallic, carbon-based, and polymeric nanomaterials: transforming dairy farming practices for sustainability. Kothari D, Kumar A. Food Chem X. 2025 Jun 7;29:102640.

Nanotechnology presents transformative solutions for the challenges facing modern dairy farming, enhancing productivity, health, and safety.
This paper explores the integration of nanomaterials in dairy farming, focusing on their applications in animal health, milk production, and quality control.
Metallic nanoparticles, carbon-based nanomaterials, polymeric nanoparticles, nano-emulsions, and natural nanomaterials offer innovative tools for veterinary medicine, diagnostics, and targeted drug delivery. These nanomaterials can improve nutrient absorption, hormonal regulation, and disease resistance, significantly boosting milk yield and quality.
Nano-biosensors facilitate real-time monitoring of animal health and milk safety, ensuring quality standards and reducing contamination risks. However, the potential toxicity, environmental persistence, and regulatory challenges of nanomaterials warrant careful evaluation.
This review paper emphasizes the need for responsible and sustainable use of nanotechnology in dairy farming, highlighting policy guidelines and recommendations for its safe and effective adoption. The findings underscore nanotechnology’s pivotal role in advancing sustainable and efficient dairy farming practices.

A Review of the Role of Paraprobiotics in the Formulation of High-Protein Ice Cream as an Advanced Functional Food. Issazadeh SA, Hatami S. Int J Food Sci. 2025 Jun 17;2025:8875377.

Paraprobiotics are nonvital bacteria that have health benefits. Recently, they have been incorporated into dairy products as supplements to probiotics. The advantages of using paraprobiotics mainly include superior resistance to processing conditions, extended shelf-life, and safer consumption by people with weaker immune systems.
In high-protein ice cream, paraprobiotics enhance freezing stability and eliminate the risks of microbial overgrowth and rare adverse effects. They also promote gut health, regulate immune responses, and have anti-inflammatory properties, which are important for children.
Moreover, paraprobiotics enhance the functional value of high-protein ice cream by promoting gut health and immune support, making it an ideal functional supplement for athletes and bodybuilders.
This review discusses recent developments in high-protein ice cream fortified with paraprobiotics, focusing on product stability, texture, and consumer acceptance while addressing challenges in the sensory quality of the final product.

Targeted dairy fortification: leveraging bioactive compounds to enhance nutritional value. Bagheri H, Akhavan-Mahdavi S, Rashidinejad A, et al. Crit Rev Food Sci Nutr. 2025 Jun 30:1-25

Dairy products, rich in nutrients, are crucial for human health and disease prevention. Recent trends focus on enhancing their nutritional value by fortifying them with bioactive compounds from plant and animal sources. Scientific evidence suggests these compounds can improve public health by potentially treating and preventing diseases, including cancer.
This systematic review discusses advances in dairy product fortification with health-promoting compounds, highlighting their role in correcting nutritional deficiencies and reducing chronic disease risk.
Innovative delivery systems are being developed to improve the stability and functionality of these compounds in fortified dairy products. Despite challenges in maintaining the physical, textural, and sensory qualities of dairy products, fortification is a promising public health strategy.
The review calls for interdisciplinary research to better understand the bioavailability, effectiveness, and long-term health impacts of bioactive compounds in dairy foods. Such research could inform best practices and policy recommendations.
Using dairy products as carriers for bioactive compounds can significantly improve nutritional status and reduce the global burden of chronic diseases, making it a strategic approach to public health nutrition.
This review cautiously evaluates current evidence, particularly regarding chronic disease prevention, and emphasizes the need for further research on specific populations, such as children and the elderly.

Whey Proteins and Bioactive Peptides: Advances in Production, Selection and Bioactivity Profiling. Luparelli A, Trisciuzzi D, Monaci L, et al. Biomedicines. 2025 May 27;13(6):1311.

The whey protein (WP) fraction represents 18-20% of the total milk nitrogen content. It was originally considered a dairy industry waste, but upon its chemical characterization, it was found to be a precious source of bioactive components, growing in popularity as nutritional and functional food ingredients. This has generated a remarkable increase in interest in applications in the different sectors of nutrition, food industry, and pharmaceutics.
WPs comprise immunoglobulins and proteins rich in branched and essential amino acids, and peptides endowed with several biological activities (antimicrobial, antihypertensive, antithrombotic, anticancer, antioxidant, opioid, immunomodulatory, and gut microbiota regulation) and technological properties (gelling, water binding, emulsification, and foaming ability).
Currently, various process technologies and biotechnological methods are available to recover WPs and convert them into BioActive Peptides (BAPs) for commercial use. Additionally, in silico approaches could have a significant impact on the development of novel foods and/or ingredients and therapeutic agents.
This review provides an overview of current and emerging methods for the production, selection, and application of whey peptides, offering insights into bioactivity profiling and potential therapeutic targets. Recent updates in legislation related to commercialized WPs-based products are also presented.

Macromineral and trace element concentrations in conventional and organic milk and plant-based beverages in the UK: implications for population intakes. Wall RJ, Clegg M, Zou Y, Stergiadis S.Food Chem. 2025 Jun 9;490:145083.

A considerable global evidence base has established that there are differences between, and within, the mineral composition of milk and plant based beverages (PBB) marketed as ‘alternatives’ to milk, and that substitution of milk for PBB may increase the risk of inadequacy of some minerals in diets across different age- or sex- based demographics.
This study compared the minerals concentrations of milk (conventional n = 20; organic n = 19) to almond (conventional n = 18; organic n = 7) and oat (conventional n = 19; organic n = 13) plant-based beverages (PBB).
Milk contained more Ca, Mg, P, K, I and Zn than PBB and less Na than oat PBB. Minerals concentrations of conventional and organic milk did not differ but conventional PBBs contained more Ca, P and I than organic PBBs due to permitted fortification. Despite fortification in conventional PBBs, Ca and I concentrations were lower than in milk.
No differences were found between conventional and organic PBBs in concentrations of minerals that are not fortified, Mg, K and Zn.
Replacement of milk with fortified conventional and organic almond and oat PBB, without other dietary changes, could reduce intakes of Ca and I below recommended intakes in some demographics, and increase prevalence of insufficiency for Mg, K, and Zn.