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

Environmental Management and Sustainability

CDRF Co-Authored Review – Strategies for mitigating greenhouse gas emissions from US dairy farms toward a net zero goal. Rotz CA, Briggs K, Hristov AN, Leytem A, Young E, Hagevoort R, Mullinax D. J Dairy Sci. 2025 Jul 8:S0022-0302(25)00487-4.

The US dairy industry has set the goal of attaining greenhouse gas (GHG) neutrality by mid-century. Reaching this goal requires the implementation of multiple strategies for mitigating and offsetting GHG production.
A large range of animal feeding, manure handling, cropping and energy saving strategies were evaluated alone and in combination to quantify their potential for reducing the farmgate life cycle carbon (C) footprint of milk production.
Representative dairy farms in major dairy regions of the US were simulated without and with these mitigation strategies using the Integrated Farm System Model (IFSM). The benefit was quantified as the change in milk C footprint with a given strategy or combination of strategies compared with that of current practices in each region.
Without consideration of economic constraints, strategies were modeled for plausible and maximum possible emission reductions. For plausible scenarios, C footprint reductions achieved with individual strategies ranged from 0.3 to 18%.
Strategies with the most benefit included anaerobic digestion of manure, a covered manure storage using a flare for methane destruction, and the use of a feed additive for mitigating enteric methane. A combination of strategies provided an average reduction in the C footprint over all farms of 44%.
Offsets that might be achieved on a few farms through soil carbon sequestration or use of food waste in anaerobic digestion provided further potential reductions of 7 and 4.9%, respectively.
With the use of maximum strategies representing an upper limit in potential mitigation, GHG reductions for individual strategies ranged from 0.3 to 32%. A combination of maximum strategies gave a reduction averaging 70% over all farms, following short of GHG neutrality.
Considering alternative metrics for quantifying the global warming effects of methane as a short-lived gas in the atmosphere provided a possible short-term solution for demonstrating climate neutrality of US dairy farms. If implementation of mitigation strategies over the next several years reduced total methane from all farms at a rate greater than 1% per year, alternative metrics such as GWP* would predict no effect on global temperature rise.
For the long-term, mitigation strategies have the potential for providing large reductions in GHG emissions but achieving GHG neutrality over all US dairy farms appears improbable.

Mitigating ammonia emissions from dairy slurry storage by using brown seaweed in the diet for sustainable environmental management. Dabiri A, Baral KR, Theodoridou K, et al. Sci Rep. 2025 Jul 1;15(1):21544

Livestock production is a major contributor to ammonia (NH₃) and greenhouse gases. Brown seaweed, Himanthalia elongata, contains bioactive compounds such as phlorotannins, which can influence protein digestion and potentially reduce NH₃emissions from excreta. However, their impact on NH₃ emissions from dairy slurry during storage remains largely unexplored.
This study evaluates the effects of H. elongata and its extract on NH₃emissions from slurry when included in the diet of dairy cows.
Nine late lactation multiparous Holstein-Friesian cows were fed three diets (dry matter basis) for 22 days: 1) control: 60% grass silage and 40% concentrate; 2) 4% H. elongata, 56% grass silage and 40% concentrate; and 3) 4% seaweed extract, 56% grass silage and 40% concentrate.
Faeces and urine samples were collected separately from cows, combined at a 3:2 ratio to prepare 20 kg of slurry, and stored for six weeks to monitor NH₃emissions using the static chamber method.
Cumulative NH₃emissions were significantly reduced in the H. elongata 733.70 ± 66.46 mg N/m²) and extract (996.71 ± 26.94 mg N/m²) treatments compared to the control (1379.64 ± 92.76 mg N/m²).
These results highlight the potential of H. elongata as a sustainable solution for mitigating NH₃emissions from slurry generated in dairy farming.

Toward a circular economy: Integrative approaches to microalgal bioremediation of whey wastewater and challenges to industrial scale-up. Chen S, Radican E, Luo Y, et al. Bioresour Technol. 2025 Jul 23;436:133032.

The dairy industry accounts for the largest portion of food processing wastewater globally, impating the demand for effective wastewater treatment.
This review collects existing research to evaluate the microalgal bioremediation of whey wastewater, the primary effluent from dairy processing.
Given the great capacity of microalgae for nitrogen and phosphorus removal, the integration with aerobic activated sludge or anaerobic digestion/fermentation for organic load reduction enhances the overall treatment efficiency for whey wastewater.
Membrane technologies are emphasized for enabling simultaneous microalgae cultivation and biomass separation from wastewater within a single reactor, maximizing the cost-effectiveness of such systems.
Finally, the challenges related to commercial scalability from experimental design, wastewater variability, and microalgal safety are discussed, along with feasible solutions.
Consequently, the high compatibility of microalgae cultivation with conventional wastewater treatment processes, together with the development of supporting technologies, facilitates the establishment of industrial-scale microalgae-based whey wastewater treatment systems.

Innovative bacterial consortia for simulated dairy wastewater treatment: improving COD removal efficiency. Patil M, Kshirsagar P, Dhakephalkar P, Gore S, Lanjekar V. Bioprocess Biosyst Eng. 2025 Jul 16.

Dairy industry generates wastewater characterized by organic components, predominantly composed of proteins and fats, which can be effectively treated through biological processes.
The present study aims to develop a bacterial consortium for bio-augmentation to enhance the treatment of simulated dairy wastewater.
A total of 75 bacterial isolates were obtained using direct (DI) and enrichment-isolation (EI) methods. Among these, four strains exhibiting the highest proteolytic and lipolytic activities within 24 h were selected for further investigations.
The selected strains were identified by 16S rRNA gene sequencing as Massilia (DSSC1), Brevibacillus (ENAT1), Pseudomonas (ENOG5), and Lysinibacillus (ETOG2). The biodegradation potential of individual strains and their consortium was assessed through COD reduction in simulated dairy wastewater.
The individual bacterial strains achieved COD reductions from an initial concentration of 3.82 g/L to 2.95, 2.81, 2.48, and 2.89 g/L. In contrast, bio-augmentation with the bacterial consortia reduced COD to 2.19 g/L, resulting in a 26-86% higher reduction compared to the individual strains.
This study presents the first report on the use of a novel approach of diffusion-based assay to develop an effective and innovative bacterial consortium for efficient dairy wastewater treatment. These findings highlight the potential of this approach toward enhancing biodegradation efficiency and advancing sustainable wastewater management practice.

Bacterial Communities of House Flies from Beef and Dairy Cattle Operations are Diverse and Contain Pathogens of Medical and Veterinary Importance. Neupane S, Talley JL, Nayduch D, et al. Curr Microbiol. 2024 Oct 30;81(12):433.

Adult house flies (Musca domestica L.) are important reservoirs and mechanical vectors of bacteria in livestock operations. House fly bacterial communities are influenced by their local environment, yet a comprehensive understanding of bacterial diversity, pathogen prevalence, and bacterial source is not fully understood.
Researchers characterized bacterial communities from adult female house flies and associated manure samples from beef and dairy cattle farms in Kansas, Oklahoma, and Texas over four months (July-October).
Bacterial community composition in flies and manure reflected the local environment, and house flies shared the majority (≥ 99%) of bacterial taxa with manure. The variability of bacterial diversity was greater among individual fly (species richness range: 48-1747) samples than manure (species richness range: 345-1162).
Bacterial taxa of veterinary and medical importance such as Corynebacterium, Turicibacter, Staphylococcus, Streptococcus, and Acinetobacter were highly prevalent in flies, constituting core bacterial communities. The prevalence of bacterial taxa associated with bovine keratoconjunctivitis (IBK) and bovine respiratory disease (BRD) was higher in flies than in manure and prevalence varied monthly.
This study underscores the crucial role house flies play as carriers of cattle pathogens, contributing to their dissemination among animals and to off-site locations, where they pose a threat to surrounding communities and agricultural operations.

Rumen metagenome as a genomic selection target to reduce enteric methane emissions. Sepulveda BJ, González-Recio O, Pryce JE, et al. J Dairy Sci. 2025;108(8):8619-8636.

Ruminant digestion emits methane, a potent greenhouse gas contributing to global warming and reducing feed efficiency. Reducing enteric methane emissions (EME) through breeding decisions is theoretically possible, yet measuring these emissions on commercial farms is currently challenging and costly.
It is common for EME to be measured using different technologies, which may show weak correlations between them, complicating the combination of reference populations, especially between countries.
Here, using the same sequencing strategy, researchers identified a group of ruminant metagenomic features (a core) present in at least 90% of 410 dairy cows in Australia and 434 in Spain. With subsets of this core (the breeding core subsets) the researchers estimated larger reductions on EME than using direct selection on EME.
A combination of direct selection on EME and indirect selection on the breeding core subsets was estimated to produce even larger reductions. Combining the principal components of the core with some genera, Kyoto Encyclopedia of Genes and Genomes ontology and Clusters of Orthologous Groups could enhance EME reductions in breeding programs.
The researchers estimated an EME reduction of 0.41 phenotypic standard deviations per generation by selecting the top 30% of individuals with desirable ruminal microbiota profiles.
These results suggest that rumen metagenome features could be used as selection criteria for genomic selection programs to reduce EME, as many of these features are heritable and correlated with EME. Features in the core could connect EME from different cattle populations, irrespective of the methane phenotype used in those populations.

The antimethanogenic efficacy and fate of bromoform and its transformation products in rumen fluid. Posman KM, Iacono G, Archer SD, et al. Sci Rep. 2025 Jul 11;15(1):25171.

Enteric methane emissions from ruminant livestock are a significant source of atmospheric methane. Efforts to address rising atmospheric methane concentrations have led to an expansion of research into mitigating enteric methane production.
One of the most effective approaches utilizes bromoform-containing feed supplements, such as the algae Asparagopsis spp., to inhibit methanogenesis in the rumen. Understanding the fate and persistence of bromoform in the rumen is important for developing safe, effective products and feeding strategies.
This study conducted a series of in vitro rumen fluid experiments monitoring bromoform, dibromomethane, and bromomethane concentrations, methane production and several biochemical parameters to understand the inhibitory thresholds and degradation processes of these compounds.
Analysis of the rumen fluid confirmed bromoform is rapidly dehalogenated. The half-life of bromoform was 26 min, coinciding with the production of dibromomethane accumulating to 22.1% of the initial bromoform amendment, but no bromomethane was detected.
Dibromomethane demonstrated a considerably longer half-life of 775 min. In separate dose-response experiments, bromoform, dibromomethane and bromomethane all exhibited anti-methanogenic activity. Bromoform and dibromomethane produced sigmoidal-relationships between concentration and inhibition at approximately 1-2 µM, and yielded similar effective concentration values (EC50s) for antimethanogenic activity.
Experiments using Asparagopsis taxiformis algae revealed less accumulation of bromoform and formation of dibromomethane, likely driven by a slower release from the seaweed material. The A. taxiformis dose response was less effective at inhibiting methane per mole of bromoform added compared with direct bromoform additions.
These results have significant implications for understanding the dynamics of bromoform-mediated methane inhibition and will aid the development of effective halocarbon additives, feeding strategies, and testing protocols for bromoform and its degradation byproducts.

High-frequency data reveal limits of adaptation to heat in animal agriculture. Palandri C, Frank EG, Fishman R, et al. Sci Adv. 2025 Jul 4;11(27):eadw4780.

Understanding the impacts of climate change on food systems is a key research priority, but important sectors and the scope for adaptation remain underexplored.
Here, researchers analyze more than 320 million daily observations of milk production across 12 years, paired with survey data, to provide estimates of the effect of humid heat and the scope for adaptation.
Results indicate that extreme heat reduces milk yield by up to 10%, with effects that persist for more than 10 days. Effects are stronger when cows are at more productive stages, suggesting a productivity-resilience trade-off.
Cooling infrastructure and management adjustments were widely adopted over the preceding two decades, but only partially mitigate these losses, reducing them by less than half.
Given the technological advancement and the representation of the climate of key producing countries in our sample, these results suggest that adaptation strategies, even those at the technological frontier, may be insufficient to address climate change damages.

Animal Health and Food Safety

UC ANR/UC Davis Research – Annual and Seasonal Trends in Mastitis Pathogens Isolated from Milk Samples from Dairy Cows of California’s San Joaquin Valley Dairies Between January 2009 and December 2023. Bruno DR, Tonooka KH, Lehenbauer TW, Aly SS, El-Ashmawy WR. Vet Sci. 2025 Jun 21;12(7):609.

Bovine mastitis is a significant disease affecting dairy cattle worldwide, impacting milk quality and farm profitability. Understanding pathogen distribution is crucial for effective disease management.
This study analyzed 319,634 individual cow milk samples submitted to the UC Davis Milk Quality Laboratory between 2009 and 2023 to assess pathogen prevalence, seasonal variations, and long-term trends.
Routine microbiological cultures identified major and minor mastitis pathogens, with additional testing for Mycoplasma Statistical analyses evaluated annual and seasonal trends in bacterial isolation rates.
Results indicated that environmental pathogens, particularly non-aureus staphylococci and coliforms, were most frequently isolated, while contagious pathogens (Staphylococcus aureus, Streptococcus agalactiae, and Mycoplasma) were less prevalent.
Seasonal trends revealed higher contamination rates in Winter and increased no-growth samples in Summer.
The study also observed a decline in sample submissions in recent years, possibly reflecting evolving dairy management practices. These findings provide a comprehensive perspective on mastitis pathogen dynamics in California’s Central Valley, supporting improved milk quality control measures and tailored mastitis prevention strategies.

Experimental infection and viral pathogenesis of a human isolate of H5N1 highly pathogenic avian influenza strain in Jersey cows. Faccin FC, Gay LC, Perez DR, et al. Res Sq. 2025 Jun 25:rs.3.rs-6915991.

Highly pathogenic avian influenza H5N1 viruses have circulated globally since 1996. In recent years, clade 2.3.4.4b H5N1 viruses have crossed the species barrier into multiple species, including dairy cattle, causing a significant decrease in milk production and rapid spread across multiple U.S. states in 2024.
Previous studies have demonstrated that Holstein cows are susceptible to H5N1 infection in laboratory settings, mirroring field observations. To investigate whether Jersey cows are susceptible to H5N1 infection and their potential as an experimental model, researchers inoculated three Jersey lactating cows intranasally and intramammarily with a human H5N1 influenza virus.
Following inoculation, milk production rapidly decreased, and milk samples exhibited a colostrum-like yellow appearance. Milk production remained low for at least seven days. All three cows experienced high fever peaks within one day of inoculation. California Mastitis Test scores in milk samples from infected quarters were elevated for several days.
Infection was confirmed by high levels of viral RNA detected for several days in external and internal swabs of infected teats, and milk samples. Conversely, low levels of viral RNA were detected in the respiratory tract of infected cows.
These findings confirm that Jersey cows are susceptible to H5N1 infection and establish them as a valuable experimental model for studying disease pathogenesis and developing effective vaccines.

A scoping review on pair housing dairy calves: health and performance outcomes and tactics to reduce cross-sucking behavior. Plaugher GD, Cantor MC. Front Vet Sci. 2025 Jun 27;12:1568164.

Calves raised in pairs or triplets often experience better growth performance outcomes when compared to their individually housed peers. However, veterinarians may be concerned that pair housing compromises calf health, and producers are concerned about abnormal oral behavior (e.g., cross-sucking).
In this literature review, researchers evaluated the effect of pair or triplet housing vs. individual housing practices on calf health outcomes and performance since 2016. Researchers also evaluated the literature on mitigation strategies to ameliorate cross-sucking in socially housed calves.
The researchers found that when researchers used pair housing practices, there was a lack of association between housing practice and risk of bovine respiratory disease (BRD) status in all studies (100%, 7/7). Only one study lacking healthy control calves found a negative effect on calf diarrhea in week 3 (1/8 studies). However, a moderate number of researchers (57%, 4/7) did not use a validated clinical scoring system to diagnose calves with BRD status.
All researchers who fed calves at least 7 L/day of milk and recorded calf starter intakes found that pair-housed calves consumed more calf starter either preweaning or post-weaning (100% 6/6). However, growth benefits were only observed in 4 studies, in which 75% fed calves at least 7 L/day of milk.
Cross-sucking is mitigated by providing socially housed calves with an outlet for oral behavior, such as a teat for milk feeding, offering at least 7 L/day of milk, offering a teat with starter, and forage.
The researchers recommend that future studies investigating social housing utilize validated clinical scoring systems for calf health monitoring, report disease diagnostic criteria, and feed ≥ 7 L/day of milk to promote performance benefits in pair-housed calves.

Factors associated with the concentration of fatty acids in the milk from grazing dairy cows. Frizzarin M, O’Callaghan TF, Berry DP. J Dairy Sci. 2025 Jul 22:S0022-0302(25)00559-4.

Bovine milk fat contains ∼400 different fatty acids, with their relative concentration being highly variable and influenced by (or associated with) intrinsic and extrinsic factors such as diet, breed, and lactation stage.
Using predicted fatty acids from milk mid-infrared spectra, the objectives of the present study were to (1) quantify the association between cow parity, lactation stage, breed, heterosis, and recombination loss with milk fatty acid composition, and (2) quantify the association between parental average genetic merit for both milk fat concentration and yield with a series of different fatty acids.
The dataset used included 644,752 milk test-day records from 303,089 cows across 2,406 commercial dairy farms. The concentration of 17 individual fatty acids as well as 16 fatty acid indices were predicted from spectral analyses of milk samples.
The concentration of the different fatty acids changed throughout lactation and across calendar months, coinciding with the seasonal profile in pasture quality, especially during the summer months.
Multiparous cows were characterized by milk with a higher concentration of saturated and short-chain fatty acids, along with a lower concentration of unsaturated, medium-chain, and long-chain fatty acids.
Jersey bloodline was associated with a higher concentration of milk saturated and short-chain fatty acids, along with a lower concentration of unsaturated, medium-chain, and long-chain fatty acids compared with Holstein-Friesians.
Genetic merit for fat yield or fat percentage was associated with a higher concentration of saturated fatty acids and a lower concentration of unsaturated fatty acids.

Per-and polyfluoroalkyl substances (PFAS) in milk and dairy products: a literature review of the occurrence, contamination sources, and health risks. Hossini H, Massahi T, Parnoon K, Nouri M. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2025 Jul 28:1-13.

Per-and polyfluoroalkyl substances (PFAS) are man-made chemicals valued for their unique characteristics, such as their ability to withstand heat, water, and oil. These compounds are widely utilized across a range of applications. Therefore, the existence of these compounds in the environment and their accumulation in various ecosystems is a cause for concern regarding their potential health risks.
Considering the importance of dairy products in the human diet, this review examines the global occurrence, sources, and health risks of PFAS contamination in milk and dairy products.
The results of the PFAS detection in the reviewed studies show a diverse contamination pattern influenced by local industrial activities, agricultural practices and regulatory measures.
PFAS have been detected in various milk and dairy products, with significant contamination near industrial areas. Milk and dairy products are indicated to be significant vectors of individual exposure to PFAS, with contamination arising primarily from dairy animal feed, water and atmospheric sediments, as well as food processing materials.
The health effects of PFAS exposure through milk and dairy product consumption, particularly the risk of endocrine disruption, immunosuppression, and carcinogenicity, are also discussed.
This review highlights the need for global standards and policy measures, encompassing stricter regulations on industrial emissions, agricultural practices, and more, to effectively reduce PFAS contamination in milk and dairy products and safeguard consumer health.

A fluid milk spoilage simulation framework reveals the need for spoilage intervention strategies that account for frequency of bacterial postpasteurization contamination. Su J, Murphy SI, Qian C, et al. J Dairy Sci. 2025 Jul 8:S0022-0302(25)00497-7.

Postpasteurization contamination (PPC) with gram-negative bacteria and the growth of spore-forming bacteria are major causes of fluid milk spoilage, typically leading to sensory defects when bacterial concentrations exceed 6 log₁₀cfu/mL. Existing models focus on individual spoilage pathways, limiting their ability to capture the complexity of milk spoilage.
To address this, researchers developed a simulation framework that simultaneously models the growth of both types of bacteria in high-temperature short-time pasteurized milk along a supply chain.
Dairy processing plants were categorized into 3 groups based on shelf life of historical fluid milk: long, medium, and short shelf-life plants. The researchers assumed varying initial PPC frequencies for each category, with ranges of 0% to 33% for long, 34% to 66% for medium, and 67% to 100% for short shelf-life plants.
Shelf life, defined as when 25% of milk containers exceeded 6 log₁₀cfu/mL, was predicted as 25, 12, and 8 days for long, medium, and short shelf-life plants, respectively. These predictions aligned with observed bacterial growth in commercial milk stored at 6°C, with the percentage of milk containers exceeding 6 log₁₀ cfu/mL on d 14 falling within the fifth to 95th percentiles of simulated values.
Sensitivity analysis identified key parameters influencing bacterial concentrations at shelf life day 7, 14, and 21 for long, medium, and short shelf-life plants, respectively, guiding intervention strategies. What-if scenario analysis revealed that effective intervention strategies to extend shelf life vary by plant categories.
While interventions targeting spore-forming bacteria, such as microfiltration, bactofugation, and improved home storage conditions, extended the shelf life for long shelf-life milk by 3 to 5 days, PPC reduction extended shelf life by 5 and 4 days in medium and short shelf-life plants, respectively.
This simulation framework provides a comprehensive spoilage prediction tool to support data-driven decision making for fluid milk processors.

Nutrition and Health

Association between dairy intake and multiple health outcomes: a scoping review of systematic reviews and meta-analyses. Akyil S, Schwingshackl L, Hauner H, et al. Eur J Clin Nutr. 2025 Jul 26.

Food-based dietary guidelines acknowledge non-fortified dairy foods as a source of multiple essential vitamins and minerals as well as high-quality protein. Considering the cultural significance of dairy foods in our diet and the increasing prevalence of non-communicable diseases, it is essential to continuously evaluate the entirety of data regarding the impact of dairy consumption on various health-related outcomes.
A systematic literature search was performed in three databases: Medline, Embase, and Web of Science.
Researchers identified 95 reports encompassing five dairy exposure categories on 29 different health outcomes.
Out of 281 associations identified, 37.7% linked dairy consumption to a reduced risk, while 48.0% showed no association with disease risk. Inconclusive results were found in 10.0% of the associations, and 4.3% indicated an increased risk of adverse health outcomes.
Overall, the evidence suggests that consuming dairy is not associated with an increased risk of non-communicable diseases or mortality. In fact, it may moderately reduce the risk of several health outcomes, including adverse cardiovascular outcomes and certain cancers such as bladder, breast, colorectal, liver, oral, and ovarian.
Some studies have also linked dairy consumption to improved body composition, lower rates of type 2 diabetes, and better bone health.

UC Davis Authored Review – Impact of Fermented Dairy on Gastrointestinal Health and Associated Biomarkers. Bui G, Marco ML. Nutr Rev. 2025 Jul 24:nuaf114. doi: 10.1093/nutrit/nuaf114.

In this narrative review, researchers examined observational and randomized controlled trials investigating the effects of fermented dairy foods, including yogurt, fermented milk, kefir, and cheese, on gastrointestinal (GI) symptoms and/or GI biomarkers of health.
GI health biomarkers encompassed measurements of intestinal integrity or permeability, immune responses, fecal microbiota, and fecal short-chain fatty acids (SCFAs).
Studies on probiotic-containing fermented dairy foods were included if the primary focus was the fermented dairy food, not specific probiotic strains.
Thirty-seven reports met the inclusion criteria and encompassed studies on healthy children, healthy adults, or individuals with underlying conditions. Twenty-one of these studies included fermented dairy products with probiotic strains.
No study reported a harmful impact of fermented dairy on gut health. Ten studies reported no benefit of fermented dairy on GI symptoms or immune biomarkers compared with milk or when no dairy was consumed. The remaining studies described significant changes in one or more gut symptoms or biomarkers with fermented dairy intake.
Improvements in GI symptoms, such as abdominal pain or discomfort, flatulence, constipation, and IBS severity, were found in most studies for which such symptoms were assessed.
Reductions in intestinal inflammatory markers, specifically serum TNFα levels, were found to be associated with fermented dairy intake.
In several trials, significant alterations to the gut microbiota or increased levels of fecal SCFAs following fermented dairy intake were measured, but not all of those studies incorporated clinically relevant outcomes.
New investigations evaluating the impact of fermented dairy on gut health should build upon the findings of these prior studies, considering target populations, underlying health conditions, and relevant gut health end points.

Yogurt and health: a focus on its matrix. Tremblay A, Drouin-Chartier JP, Marette A, Drapeau V. Crit Rev Food Sci Nutr. 2025 Jul 1:1-10.

Research and clinical experience in nutrition have emphasized the merits of some dietary patterns, e.g., the Mediterranean diet, to obtain health-related benefits. This has also been the case of specific foods such as yogurt which has been tested using different approaches and under various conditions.
As described in this paper, there is a quasi-consensus among population studies about the protective relationship of regular yogurt consumption with incidence of overweight and type 2 diabetes. This is concordant with laboratory-based experimentation and clinical trials showing that yogurt consumption induces favorable effects on many key components of metabolic homeostasis and energy balance.
The benefits of yogurt consumption also seem to be partly explained by its status of fermented food which involves the influence of yogurt on the gut microbiota and the reciprocal role of some bacterial-derived molecules on metabolic regulation. In clinical nutrition, novel education approaches benefit from the versatility of yogurt and its high nutrient density to promote healthy eating behaviors and habits as well as cardiometabolic benefits.
In summary, yogurt, especially plain yogurt, should be part of healthy eating habits because of its high nutritional value, its flexible food matrix, its beneficial bacterial components, and its versatility under usual feeding conditions.

The association between dairy and bone quality in Puerto Rican adults varies by dairy food and fat content. Merrill LC, Noel SE, Mangano KM, et al. JBMR Plus. 2025;9(8):ziaf094.

Dairy foods have been shown to improve BMD, a measure of bone quantity, yet there is little understanding of their influence on measures of bone quality.
The aim of this study was to examine associations of dairy intakes with two measures of bone quality: bone material strength index and spinal trabecular bone score, and the potential mediating role of inflammation, among adults from the Boston Puerto Rican Osteoporosis Study.
This cross-sectional analysis included dietary intake assessed with a culturally tailored food frequency questionnaire. Dairy food groups were calculated as total dairy (milk, yogurt, and cheese), milk, cheese, yogurt, desserts, non-fat, and fat-containing dairy. Bone material strength index (n= 138) was measured using micro indentation with the Osteoprobe, and spinal trabecular bone score (n = 412) was calculated from DXA scans.
Participants were 77.4% female with mean age 70.5 ± 6.9 yr. Higher intakes of total dairy and milk were associated with bone material strength index. Higher intake of fat-containing dairy was positively associated with spinal trabecular bone score, while higher intake of non-fat dairy was inversely associated with spinal trabecular bone score. Inflammatory cytokines were not identified as mediators of these associations.
Dairy food intakes were associated with measures of bone quality; however, the foods that predicted bone material strength index and spinal trabecular bone score differed.
Bone material strength index was influenced by total dairy and milk, while spinal trabecular bone score was influenced by dairy fat content. Future studies should examine the impact of dairy matrix components on immune and inflammatory pathways.

Consumption of dairy products and prevalence of depression and anxiety among adults. Mofidi-Nejad M, Milajerdi A, Khadem A, et al. J Health Popul Nutr. 2025 Jul 10;44(1):247.

No earlier study has examined the association between dairy intake and prevalence of depression and anxiety in Middle Eastern population.
This cross-sectional study was done to investigate the association between consumption of total dairy intake and prevalence of depression and anxiety in a large group of adult population in Isfahan, Iran.
Dairy intake was assessed for 3362 participants using a validated 106-item Willet-format dish-based semi-quantitative FFQ. A validated questionnaire of Hospital Anxiety and Depression Scale was used to examine depression and anxiety. Researchers defined scores of > 8 as depressed and anxious people in this analysis.
Mean age of study population was 36 years. Participants in the highest quintile of dairy intake had a 40% lower chance for depression compared to those in the lowest quintile (OR = 0.60) in crude model. This association remained significant after controlling for several confounders (0.57).
Although the researchers observed a significant association between dairy intake and anxiety in crude model (OR: 0.63), the association was not significant when they took into account potential confounders (0.63).
In conclusion, the study showed an inverse association between consumption of dairy products and depression but the results for anxiety were not significant. Further studies, in particular of prospective nature, are recommended to confirm our findings.

Probiotic-mediated modulation of gut microbiome in students exposed to academic stress: a randomized controlled trial. Vázquez-Castellanos JF, Maciel LF, Raes J, et al. NPJ Biofilms Microbiomes. 2025 Jul 21;11(1):140.

Probiotics have been widely tested for their effect on mental well-being, albeit with heterogeneous outcomes. Direct and indirect effects through the gut microbiome might lie at the basis of these observations.
Here, in a post-hoc analysis, researchers assessed the effect of 4-week consumption of a probiotic candidate strain on the gut microbiome in students exposed to academic stress.
Healthy students were randomized to consume a fermented milk product with Lacticaseibacillus rhamnosus CNCM I-3690 (N = 39) or an acidified non-fermented milk product (N = 40) twice daily for 4 weeks before academic exams.
Stress and anxiety were assessed using both objective and self-reported markers.
Changes of alpha-diversity markers and community shifts from baseline (beta diversity) were lower in L. rhamnosus treated individuals over controls, suggesting lower overall changes of gut microbiota during psychological stress in the Probiotic group.
The intake of L. rhamnosus CNCM I-3690 induced differential abundance of some species, such as the maintenance of the quantitative abundance of Ruminococcus bicirculans, and co-varied with species, which differed according to visits (i.e., stress level), suggesting a potential beneficial effect of the strain before the highest increase of stress level.
The higher quantitative abundance of F. prausnitzii induced by the probiotic intake was associated with lowered self-reported anxiety levels before the exam. Functional analysis revealed minor changes upon intake of the probiotic strain.
Taken together, using a quantitative framework, we found that L. rhamnosus CNCM I-3690 has a potential effect on gut microbiome response to stress, although further studies are needed to better understand the precise interaction.

Lactose: beneficial or harmful? Evidence-based dietary approaches. Loria-Kohen V, Bermejo LM, Salas-González MD, López-Sobaler AM. Nutr Hosp. 2025 Jul 18.

The consumption of milk and derivatives is essential throughout life. Lactose plays a significant role due to its prebiotic effect, potential implications for the gut microbiota, and impact on bone and gastrointestinal health. Therefore, it should not be avoided unless a medical condition justifies it.
It is crucial to distinguish between lactase non-persistence, lactose malabsorption, and lactose intolerance. A proper diagnosis should be the starting point to prevent the unnecessary removal of milk, dairy products, or lactose from the diet due to trends or misinformation rather than actual intolerance.
The primary strategy for managing lactose intolerance is to mitigate symptom severity through dietary modifications while ensuring adequate nutrient intake.

Innovation, Social Science, and Dairy Alternatives

Human infections with highly pathogenic avian influenza A(H5N1) viruses in the United States from March 2024 to May 2025. Rolfes MA, Kniss K, Olsen SJ, et al. Nat Med. 2025 Jul 25.

The persistent panzootic spread of highly pathogenic avian influenza HPAI A(H5N1) viruses and continued detection of human cases presents an ongoing threat to public health.
Between March 2024 and October 2024, 46 human cases of HPAI A(H5N1) had been detected in the United States. Between November 2024 and May 2025, an additional 24 cases have been reported for a total of 70 human cases of HPAI A(H5N1): 41 were exposed to dairy cows, 24 to commercial poultry, 2 to backyard poultry, and 3 had an unidentified source of exposure. All sequenced viruses were clade 2.3.4.4b.
Overall, 62 cases (89%) reported eye redness, 32 (46%) fever, and 29 (41%) respiratory symptoms; 54 of 67 cases (81%) reported receiving antiviral treatment.
Most illnesses were mild; however, four patients were hospitalized. Of the hospitalized patients, three had pneumonia and one died.
No human-to-human transmission was detected.
Occupational exposure to infected animals was a risk factor for HPAI A(H5N1) virus infection and the risk to the general population remains low.

Artificial intelligence meets dairy cow research: Large language model’s application in extracting daily time-activity budget data for a meta-analytical study. Lamanna M, Muca E, Cavallini D, et al. J Dairy Sci. 2025 Jul 18:S0022-0302(25)00522-3.

In recent years, artificial intelligence (AI) has played an increasingly crucial role in scientific research, revolutionizing the way data are collected, analyzed, and interpreted. Among the many advances in AI, generative models, particularly large language models (LLM), have proven transformative due to their ability to generate text, analyze complex information, and support knowledge synthesis.
This study investigates the application of ChatGPT-4 in extracting and classifying behavioral data from scientific literature, focusing on the daily time-activity budget of dairy cows.
Accurate analysis of time-activity budgets is crucial for understanding dairy cow welfare and productivity. Traditional methods are time-intensive and prone to bias. This study evaluates the accuracy and reliability of ChatGPT-4 in data extraction and data categorization, considering explicit, inferred, and ambiguous labels for the data, compared with human analysis.
A collection of 55 papers on dairy cow behavior were used in the studies. Data extraction for eating, ruminating, and lying behaviors was performed manually and via ChatGPT-4. The artificial intelligence (AI) model’s accuracy and labeling performance were assessed through descriptive and statistical analyses. Mixed model analysis was used to compare human and AI outcomes.
Artificial intelligence and human time budget data showed significant differences for eating and ruminating but not for lying. ChatGPT-4 estimated daily eating time at 22.3% compared with 23.8% by humans. For ruminating, AI reported 33.4% against 31.7% by humans. Daily lying times were nearly identical, with AI at 44.4% and human analysis at 44.2%.
The global accuracy in data extraction was ∼75%, and labeling accuracy reached 67.3%, with significant variability across behavioral categories.
In general, the AI model demonstrates moderate accuracy in extracting and categorizing behavioral data, particularly for inferred and ambiguous data. However, explicit data extraction posed challenges, highlighting AI’s dependence on input quality and structure.
The consistency between AI and human analyses for lying behavior underscores AI’s potential for specific applications. ChatGPT-4 offers a promising complementary tool for behavioral research, enabling efficient and scalable data extraction. However, improvements in AI algorithms and standardized reporting in scientific literature are essential for broader applicability.
The study advocates for hybrid approaches combining AI capabilities with human oversight to enhance the reliability and accuracy of dairy cow behavioral research.

Towards a More Holistic Comparative Assessment of Plant-Based Alternative Beverages and Dairy Milk: A True Cost Accounting Approach. Bellon MR, Benard N, Coghlan JE, Merrigan K. Foods. 2025;14(13):2196.

There is a growing market for plant-based alternative beverages (PBAs) promoted as alternatives to dairy milk. Part of their popularity is that consumers consider them better for both the environment and human health. These perceptions, however, may not be entirely supported by scientific evidence.
A holistic comparison of dairy milk and PBAs is difficult because their prices typically do not reflect their environmental and nutritional health impacts, although PBAs tend to be significantly more expensive than dairy milk.
Here, researchers integrate key results from the scientific literature using a True Cost Accounting (TCA) approach to compare dairy milk and five PBAs based on their market retail price and a quantification-and when possible, monetization-of key environmental, nutritional, and social impacts: Global Warming Potential (GWP), dietary risks, and forced labor, respectively.
The researchers compare whole dairy milk with five PBAs: soy, almond, oat, coconut, and pea, which account for 97% of retail market sales in the USA.
The results show that while environmental, nutritional, and social benefits attributed to PBAs compared to dairy milk exist and can be significant, they are heterogenous, and for some PBAs, they may not be as significant as commonly perceived, particularly when the price premium they command are considered.

The amino acid composition of commercially available vegan meat and dairy analogues. Domić J, van Loon LJ, Grootswagers P, et al. Br J Nutr. 2025 Jul 31:1-31.

Plant-based meat and dairy analogues contain less protein than their animal-based counterparts and rely on various plant protein sources, which frequently display incomplete amino acid (AA) profiles that do not reflect dietary requirements due to low quantities of one or more essential AA (EAA).
There is little insight in the AA profiles of most of these plant-based analogues. We assessed the AA composition of 40 plant-based meat and dairy analogues that were commercially available in The Netherlands in March 2023, and compared their EAA profile to dietary requirements and to the EAA profile of their meat and dairy counterparts.
Total protein contents were lower in most analogues when compared to their animal-based counterparts (meat analogues, n= 16 (80%); lunch meats and cheese analogues, n = 10 (100%); milk and yoghurt analogues, n = 9 (90%)) and accompanied by lower EAA contents.
In reference to dietary requirements, the sum of the total EAA contents was adequate in all but one of the analogues. Nevertheless, all analogues displayed deficiencies in one or more specific EAA.
Methionine contents were most frequently low (n= 39; 98%), followed by lysine contents (n = 11; 28%). Essential AA compositions varied between analogues irrespective of the protein source(s) used.
In conclusion, plant-based meat and dairy analogues exhibit incomplete EAA profiles, which may compromise adequate protein nutrition in plant-centered diets.

Effect of Almond Milk Versus Cow Milk on Postprandial Glycemia, Lipidemia, and Gastrointestinal Hormones in Patients with Overweight or Obesity and Type 2 Diabetes: A Randomized Controlled Clinical Trial. Dhaver S, Al-Badri M, Hamdy O, et al. Nutrients. 2025;17(13):2092.

Almond milk is often seen as a healthier alternative to cow milk. However, its effect on postprandial glycemia compared to 2% milk is unclear.
Therefore, researchers compared the postprandial glycemic effect of almond milk versus carbohydrate- or caloric-matched 2% milk, each served with oatmeal to patients with type 2 diabetes (T2D).
In this crossover, three-way, open-label study, 22 participants (mean age 66 ± 7.4 years, 36% female), with T2D and overweight or obesity, consumed oatmeal served with almond milk (ALM), carbohydrate-matched 2% milk (MLKCRB), or calorie-matched 2% milk (MLKCAL) on separate days and in a random order.
The primary outcome was glucose incremental area under the curve for 240 min (iAUC0-240). The secondary outcomes included postprandial serum insulin, glucagon, plasma free fatty acids (FFAs), serum triglycerides, leptin, and gastrointestinal hormones (PYY, active GLP-1, GIP, amylin, cholecystokinin, and ghrelin).
The researchers did not find any difference in either the primary endpoint or secondary endpoints between the three groups. However, iAUC0-240 for insulin and glucagon was significantly higher in MLKCRB vs. ALM.
In conclusion, almond milk does not offer any additional glycemic benefit over 2% milk and does not differ in its postprandial effects on FFAs, serum triglycerides, leptin, and gastrointestinal hormones over 4 hours. Nonetheless, carbohydrate-matched 2% milk elicited greater insulin and glucagon response compared to almond milk, warranting further investigation into its long-term implications.