Dairy Research Bulletin
Selected Articles from October 2021

Environmental Management and Sustainability

The Dairy Cow Slurry Composition Used as Organic Fertilizer Is Influenced by the Level and Origin of the Dietary Protein. Vicente F, Elouadaf D, Sánchez-Vera A, Soldado A, De La Torre-Santos S, Martínez-Fernández A. Animals (Basel). 2021;11(10):2812.

  • Less than 30% of dairy cattle’s nitrogen ingested is retained in milk. Therefore, large amounts of nitrogen can be excreted in manure and urine with a potential environmental impact. In addition, some legume forages can be more susceptible to proteolysis during the silage process than grasses, and dairy cows fed these legume silages would excrete a larger quantity of nitrogen in slurry.
  • The objectives of this work were to evaluate the amount of nitrogen excretion in dairy cows fed different protein levels and legume silages with a view to improve the slurry quality as a co-product that can be used as fertilizer.
  • Two double 3 × 3 Latin square trials were carried out in order to study three different protein levels (high, medium, and low) and three different silages (grass, faba bean, and field pea). Dry matter intake, milk production, and composition were not affected by treatments.
  • The excretion of ammonia-N in the urine was almost four times lower in the diet with the lowest protein level. The ammonia-N in the urine was twice as high with the pea silage than faba bean and grass silages.
  • In conclusion, the diet containing 13% of protein meets the protein requirement for lactating cows producing 31 kg daily, with low nitrogen excretion in the urine, and the main pathway for the excretion of surplus nitrogen from legume silages is through urine and the metabolization of pea silage protein goes toward ammonia-N.

Cooperation between specialized livestock and crop farms can reduce environmental footprints and increase net profits in livestock production. Ma Y, Hou Y, Dong P, Velthof GL, Long W, Ma L, Ma W, Jiang R, Oenema O. J Environ Manage. 2021 Oct 23;302(Pt A):113960.

  • The rapid specialization of livestock production has contributed to spatially decoupled crop and livestock production, leading to various environmental pollution issues. Some regional agro-environmental policies have recently promoted the coupling of specialized crop and livestock farms through cooperation. However, the environmental and economic performances of such cooperation remain unclear.
  • This study investigated multiple environmental footprints of two contrasting production systems: cooperative crop-livestock systems (CCLS) and decoupled specialized livestock systems (DSLS), using survey data of 87 ruminant farms in Northwest China.
  • Results show that farms in CCLS had lower net greenhouse gas (GHG) emissions (12-29%), lower reactive nitrogen (Nr) emissions (21-40%), lower phosphorus footprints (PF) (41-54%), and used less cropland (24-31%) per kg animal product, compared to those in DSLS.
  • The large differences in GHG emissions between the two systems were mainly related to enteric fermentation and resource production (used for feed production). The differences in Nr emissions and PF were mainly related to manure management.
  • Net profits per kg animal product were higher in CCLS (13-35%) than in DSLS, and most profits originated from lower purchasing costs of feed and young livestock. Net profits and environmental footprints were negatively correlated, suggesting an environmental and economic win-win situation for CCLS.
  • This study provides science-based evidence to support policymakers and specialized farms to close nutrient loops between crop and livestock production sectors through regional cooperation.

Long-Term Mootral Application Impacts Methane Production and the Microbial Community in the Rumen Simulation Technique System. Brede J, Peukert M, Egert B, Breves G, Brede M. Front Microbiol. 2021 Oct 8;12:691502.

  • Methane emissions by ruminants contribute to global warming and result in a loss of dietary energy for the animals. One possibility of reducing methane emissions is by dietary strategies.
  • In the present trial, researchers investigated the long-term effects of Mootral, a feed additive consisting of garlic powder (Allium sativum) and bitter orange extracts (Citrus aurantium), on fermentation parameters and the microbial community in the rumen simulation technique (RUSITEC) system.
  • The experiment lasted 38 days and was divided into three phases: an equilibration period of 7 days, a baseline period (BL) of 3 days, and experimental period (EP) of 28 days. Twelve fermentation vessels were divided into three groups (n= 4): control (CON), short-term (ST), and long-term (LT) application. From day 11 to day 27, 1.7 g of Mootral was added to the ST vessels; LT vessels received 1.7 g of Mootral daily for the entire EP.
  • With the onset of Mootral application, methane production was significantly reduced in both groups until day 18. Thereafter, the production rate returned to the initial quantity. Furthermore, the short chain fatty acid fermentation profile was significantly altered by Mootral application; the molar proportion of acetate decreased, while the proportions of propionate and butyrate increased.
  • Metabolomic analysis revealed further changes in metabolite concentrations associated with the Mootral supplementation period. The methyl coenzyme-M reductase gene copy number was reduced in the liquid and solid phase, whereas the treatment did not affect the abundance of bacteria. At the end of the baseline period, Methanomicrobia was the most abundant archaeal class.
  • Mootral supplementation induced an increase in the relative abundance of Methanomassiliicoccalesand a reduction in the relative abundance of Methanomicrobia, however, this effect was transient. Abundances of bacterial families were only marginally altered by the treatment.
  • In conclusion, Mootral has the transient ability to reduce methane production significantly due to a selective effect on archaea numbers and archaeal community composition with little effect on the bacterial community.

Assessing the carbon footprint across the supply chain: Cow milk vs soy drink. Coluccia B, Agnusdei GP, De Leo F, Vecchio Y, La Scalia G, Miglietta PP. Sci Total Environ. 2021 Oct 23:151200.

  • Since livestock product consumption could have a significant effect on tackling climate change, in the few last years, there has been an increasing consumer demand for non-dairy alternatives. Despite plant-based beverages being considered crucial to foster the transition towards sustainable diet models, no studies have yet compared the level of emissions of plant-based beverages with animal-based ones.
  • The present study aims at computing the carbon footprint of cow milk and that of soy drink and evaluating the carbon footprint results in the light of the substitutability of cow’s milk with soy drink, analyzing the potential environmental, economic, and nutritional trade-offs between the two products.
  • Results highlight that, considering the environmental perspective, soy drink could be a valid substitute of cow milk: its production has a lower carbon footprint, allowing for the achievement of food security objectives.
  • However, focusing on the economic and nutritional perspectives, the high average consumer price of soy drink is associated with an overall lower nutritional level. In order to reach the same nutritional value as 1 L of cow milk in terms of protein intake, the consumption of soy drink should be increased by 13%. Furthermore, soy drink consumption implies paying 66% more than for cow milk, when considering the same protein content.

Climate Justice and California’s Methane Superemitters: Environmental Equity Assessment of Community Proximity and Exposure Intensity. Casey JA, Cushing L, Depsky N, Morello-Frosch R. Environ Sci Technol. 2021 Oct 20.

  • Methane superemitters emit non-methane copollutants that are harmful to human health. Yet, no prior studies have assessed disparities in exposure to methane superemitters with respect to race/ethnicity, socioeconomic status, and civic engagement.
  • To do so, researchers obtained the location, category (e.g., landfill, refinery), and emission rate of California methane superemitters from Next Generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) flights conducted between 2016 and 2018.
  • The researchers identified block groups within 2 km of superemitters (exposed) and 5-10 km away (unexposed) using dasymetric mapping and assigned level of exposure among block groups within 2 km (measured via number of superemitter categories and total methane emissions).
  • The analyses included 483 superemitters. The majority were dairy/manure (n= 213) and oil/gas production sites (n = 127). Results indicate environmental injustice in methane superemitter locations. For example, for every 10% increase in non-Hispanic Black residents, the odds of exposure increased by 10%.
  • The researchers observed similar disparities for Hispanics and Native Americans but not with indicators of socioeconomic status. Among block groups located within 2 km, increasing proportions of non-White populations and lower voter turnout were associated with higher superemitter emission intensity.
  • Previously unrecognized racial/ethnic disparities in exposure to California methane superemitters should be considered in policies to tackle methane emissions.

Animal Health and Food Safety

Cows as canaries: The effects of ambient air pollution exposure on milk production and somatic cell count in dairy cows. Beaupied BL, Martinez H, Martenies S, McConnel CS, Pollack IB, Giardina D, Fischer EV, Jathar S, Duncan CG, Magzamen S. Environ Res. 2021 Oct 23:112197.

  • Exposure to air pollution, including criteria pollutants such as fine particulate matter (PM5) and ozone (O3), has been associated with morbidity and mortality in mammals. As a genetically homogenous population that is closely monitored for health, dairy cattle present a unique opportunity to assess the association between changes in air pollution and mammalian health.
  • Milk yield decreases in the summer if temperature and humidity, measured by the Temperature Humidity Index (THI). As O3levels increase with warmer temperatures, and summer PM5 may increase with wildfire smoke, dairy cows may serve as a useful sentinel species to evaluate subacute markers of inflammation and metabolic output and ambient pollution.
  • Over two years, researchers assessed summertime O3and PM5 concentrations from local US EPA air quality monitors into an auto-regressive mixed model of the association between THI and daily milk production data and bulk tank somatic cell count (SCC). In unadjusted models, a 10 unit increase THI was associated with 28,700 cells/mL increase in SCC. After controlling for ambient air pollutants, THI was associated with a 14,500 SCC increase, a 48% decrease in effect compared to the crude model.
  • Further, in fully adjusted models, PM5was associated with a 105,500 cells/mL increase in SCC. Similar results were found for milk production. Results were attenuated when high PM2.5 days associated with wildfire smoke were removed from the analyses.
  • These results support the hypothesis that PM5confounds the relationships between THI and milk yield and somatic cell count. The results of this study can be used to inform strategies for intervention to mitigate these impacts at the dairy level and potentially contribute to a model where production animals can act as air quality sentinels.

Milking system and premilking routines have strong effect on the microbial community in bulk tank milk. Sun L, Lundh Å, Höjer A, Bernes G, Nilsson D, Johansson M, Hetta M, Gustafsson AH, Saedén KH, Dicksved J. J Dairy Sci. 2021 Oct 22:S0022-0302(21)00969-3.

  • In this study, researchers investigated the variation in the microbial community present in bulk tank milk samples and the potential effect of different farm management factors.
  • Bulk tank milk samples were collected repeatedly over one year from 42 farms located in northern Sweden. Total and thermoresistant bacteria counts and 16S rRNA gene-based amplicon sequencing were used to characterize microbial community composition.
  • The microbial community was in general heterogeneous both within and between different farms and the community composition in the bulk tank milk was commonly dominated by Pseudomonas, Acinetobacter, Streptococcus, unclassified Peptostreptococcaceae, and Staphylococcus.
  • Principal component analysis including farm factor variables and microbial taxa data revealed that the microbial community in milk was affected by type of milking system. Milk from farms using an automatic (robot) milking system (AMS) and loose housing showed different microbial community composition compared with milk from tiestall farms. A discriminant analysis model revealed that this difference was dependent on several microbial taxa.
  • Among farms using an automatic milking system, there were further differences in the microbial community composition depending on the brand of the milking robot used. On tiestall farms, routines for teat preparation and cleaning of the milking equipment affected the microbial community composition in milk.
  • Total bacteria count (TBC) in milk differed between the farm types, and TBC were higher on AMS than tiestall farms. Among tiestall farms, milk from farms using a chemical agent in connection to teat preparation and a more frequent use of acid to clean the milking equipment had lower TBC in milk, than milk from farms using water for teat preparation and a less frequent use of acid to clean the milking equipment.
  • There were no significant differences in the number of thermoresistant bacteria between farm types. The evaluated factors explained only a small proportion of total variation in the microbiota data, however, despite this, the study highlights the effect of routines associated with teat preparation and cleaning of the milking equipment on raw milk microbiota, irrespective of type of milking system used.

Clinical Mastitis Incidence in Dairy Cows Housed on Recycled Manure Solids Bedding: A Canadian Cohort Study. Fréchette A, Fecteau G, Côté C, Dufour S. Front Vet Sci. 2021;8:742868.

  • Bedding can affect mammary health of dairy cows.
  • The objectives of this study were to evaluate clinical mastitis incidence in cows housed on recycled manure solids bedding and, more specifically, to determine which pathogens were involved. Researchers followed 26 recycled manure solids farms and 60 straw-bedded farms as a comparative group during 1 year (2018-2019).
  • Researchers tested 1,144 milk samples. In 54.6% of clinical mastitis cases, a single phenotype of bacteria was cultured (pure culture), while two different phenotypes were found in 16.8% of the samples (mixed culture), and no growth was observed in 14.4% of the samples. Samples with three or more phenotypes were considered contaminated and were not included in the pathogen-specific analyses (14.3% of the submitted samples).
  • The most frequently identified bacterial species in pure and mixed culture in farms using recycled manure solids were Streptococcus uberis(16.0%), Escherichia coli (13.8%), Klebsiella pneumoniae (13.2%), Streptococcus dysgalactiae (6.2%), and Staphylococcus aureus (3.4%). In straw farms, the most frequent species were  aureus (16.6%), S. uberis (11.0%), E. coli (9.1%), S. dysgalactiae (8.0%), and K. pneumoniae (1.1%).
  • The incidence of clinical mastitis (all cases together) was not higher in recycled manure solids farms compared with straw-bedded farms. However,  pneumoniaeclinical mastitis episodes were 7 times more frequent in recycled manure solids farms than in straw farms. Klebsiella pneumoniae clinical mastitis is in general severe. Producers interested in this bedding alternative need to be aware of this risk.

The Pattern of Blood-Milk Exchange for Antiparasitic Drugs in Dairy Ruminants. Imperiale F, Lanusse C. Animals (Basel). 2021;11(10):2758.

  • The prolonged persistence of milk residual concentration of different antiparasitic drugs in lactating dairy animals should be considered before recommending their use (label or extra-label) for parasite control in dairy animals.
  • The partition blood-to-milk ratio for different antiparasitic compounds depends on their ability to diffuse across the mammary gland epithelium. The high lipophilicity of some of the most widely used antiparasitic drugs explains their high partition into milk and the extended persistence of high residual concentrations in milk after treatment.
  • Most of the antiparasitic drug compounds studied were shown to be stable in various milk-related industrial processes. Thus, the levels of residues detected in raw milk can be directly applicable to estimating consumer exposure and dietary intake calculations when consuming heat-processed fluid milk.
  • However, after milk is processed to obtain milk products such as cheese, yogurt, ricotta, and butter, the residues of lipophilic antiparasitic drugs are higher than those measured in the milk used for their elaboration.
  • This review article contributes pharmacokinetics-based information, which is useful to understand the relevance of rational drug-based parasite control in lactating dairy ruminants to avoid undesirable consequences of residual drug concentrations in milk and derived products intended for human consumption.

Human Nutrition and Health

CDRF-Funded Research Effect of dietary sources of calcium and protein on hip fractures and falls in older adults in residential care: cluster randomised controlled trial. Iuliano S, Poon S, Robbins J, Bui M, Wang X, De Groot L, Van Loan M, Zadeh AG, Nguyen T, Seeman E.BMJ. 2021 Oct 20;375:n2364.

  • Dairy Australia, The California Dairy Research Foundation, and Dairy Council of California, along with several other dairy science organizations from around the world, supported a project investigating increased dairy intake with the risk of falls and fractures in an aged Australian population.
  • The purpose of this study was to assess the antifracture efficacy and safety of a nutritional intervention in institutionalized older adults replete in vitamin D but with mean intakes of 600 mg/day calcium and <1 g/kg body weight protein/day.
  • This was a two-year cluster randomized controlled trial testing 60 accredited residential aged care facilities in Australia. Participants were 7195 permanent residents with a mean age of 86 years.
  • 30 facilities were randomized to provide residents with additional milk, yogurt, and cheese that contained 56 mg/day calcium and 12/day protein achieving a total intake of 114 mg calcium/day and 69 g/day protein. The 30 control facilities maintained their usual menus, with residents consuming 700 mg/day calcium and 58 g/day protein.
  • Data from 27 intervention facilities and 29 control facilities were showed a total of 324 fractures (135 hip fractures), 4302 falls, and 1974 deaths. The intervention was associated with risk reductions of 33% for all fractures (121 v203), 46% for hip fractures (42 v 93), and 11% for falls (1879 v 2423).
  • The risk reduction for hip fractures and falls achieved significance at five months and three months, respectively. Mortality was unchanged.
  • In conclusion, improving calcium and protein intakes by using dairy foods is a readily accessible intervention that reduces the risk of falls and fractures commonly occurring in aged care residents.

CDRF-Supported Publication  Food Systems Transformation for Child Health and Well-Being: The Essential Role of Dairy. Miller GD, Kanter M, Rycken L, Comerford KB, Gardner NM, Brown KA. Int J Environ Res Public Health. 2021 Oct 8;18(19):10535.

  • Malnutrition, in all its forms, during the critical stages of child growth and development can have lifelong impacts on health and well-being. While most forms of malnutrition can be prevented with simple dietary interventions, both undernutrition and overnutrition remain persistent and burdensome challenges for large portions of the global population, especially for young children who are dependent on others for nourishment.
  • In addition to dietary factors, children’s health also faces the growing challenges of climate change, environmental degradation, pollution, and infectious disease. Food production and consumption practices both sit at the nexus of these issues, and both must be significantly transformed if we are to achieve the 2030 Sustainable Development Goals.
  • Food sources (i.e., animal-source foods vs. plant-source foods), food production practices, the effects of food processing, the impacts of a more globalized food system, and food loss and waste have all been receiving growing attention in health and sustainability research and policy discussions. Much of this work points to recommendations to reduce resource-intensive animal-source foods, heavily processed foods, and foods associated with excessive waste and pollution, while simultaneously increasing plant-source options. However, some of these recommendations require a little more nuance when considered in the context of issues such as global child health.
  • All types of foods can play significant roles in providing essential nutrition for children across the globe, and for improving the well-being and livelihoods of their families and communities. Dairy foods provide a prime example of this need for nuance, as both dairy production practices and consumption patterns vary greatly throughout the world, as do their impacts on child health and food system sustainability.
  • The objective of this narrative review is to highlight the role of dairy in supporting child health in the context of food system sustainability. When considering child health within this context it is recommended to take a holistic approach that considers all four domains of sustainability (health, economics, society, and the environment) to better weigh trade-offs, optimize outcomes, and avoid unintended consequences.
  • To ensure that children have access to nutritious and safe foods within sustainable food systems, special consideration of their needs must be included within the broader food systems transformation narrative.

Exploring the Links between Diet and Inflammation: Dairy Foods as Case Studies. Hess JM, Stephensen CB, Kratz M, Bolling BW.Adv Nutr. 2021 Oct 11;12(Suppl 1):1S-13S.

  • Systemic chronic inflammation may be a contributing factor to many noncommunicable diseases, including diabetes, cardiovascular disease, and obesity. With the rapid rise of these conditions, identifying the causes of and treatment for chronic inflammation is an important research priority, especially with regard to modifiable lifestyle factors such as diet.
  • An emerging body of evidence indicates that consuming certain foods, including dairy foods like milk, cheese, and yogurt, may be linked to a decreased risk for inflammation. To discuss both broader research on diet and inflammation as well as research on links between individual foods and inflammation, the National Dairy Council sponsored a satellite session entitled “Exploring the Links between Diet and Inflammation: Dairy Foods as Case Studies” at the American Society for Nutrition’s 2020 LIVE ONLINE Conference.
  • This article, a review based on the topics discussed during that session, explores the links between diet and inflammation, focusing most closely on the relations between intake of dairy fat and dairy foods like milk, cheese, and yogurt, and biomarkers of inflammation from clinical trials. While there is currently insufficient evidence to prove an “anti-inflammatory” effect of dairy foods, the substantial body of clinical research discussed in this review indicates that dairy foods do not increase concentrations of biomarkers of chronic systemic inflammation.

Two untargeted metabolomics reveals yogurt-associated metabolic alterations in women with multiple metabolic disorders from a randomized controlled study. Du S, Chen Y, Liu X, Zhang Z, Jiang Y, Zhou Y, Zhang H, Li Q, Xuemei Wang, Wang Y, Feng R. J Proteomics. 2021 Oct 16:104394.

  • The beneficial role of yogurt on metabolic profile has been widely reported. Yet, few studies have intended to describe the integrated metabolic alterations in response to yogurt.
  • Yogurt and milk (220 g/d) were given to 48 and 44 obese women with metabolic syndrome and nonalcoholic fatty liver disease for 24 weeks in a randomized controlled trial. Fasting serum samples were collected before and after intervention for global, untargeted metabolomics.
  • No clustering was observed between the two groups at baseline. While, a clear clustering was shown after intervention, and the yogurt group had significantly different metabolic status from the milk. The metabolites that contributed mostly to class separation were identified and involved into pathway analysis. Pathways on amino acids metabolism, fatty acid oxidation, cholesterol catabolism and choline metabolism significantly changed after yogurt intervention.
  • The study revealed the integrated metabolic alterations in response to yogurt via two metabolomics approaches, suggesting the potential mechanisms of yogurt against metabolic disorders. The finding will shed light on a more comprehensive picture of how yogurt affects host metabolism and provide theoretical foundation for dietary prevention of chronic diseases.

Dairy intake and long-term body weight status in German children and adolescents: results from the DONALD study. Hohoff E, Perrar I, Jankovic N, Alexy U. Eur J Nutr. 2021 Oct 31.

  • The research on dairy intake and body weight in children and adolescents is inconclusive.
  • The purpose of this study was to analyze the association between intake of total dairy and types of dairy [liquid dairy, solid dairy, low-fat dairy, high-fat dairy, high sugar dairy, low-sugar dairy, not fermented dairy, as well as fermented dairy] and long-term changes in body weight status and composition among children and adolescents in Germany.
  • In total, 9999 3-day dietary records collected between 1985 and 2019 by 1126 participants (3.5-18.5 years) of the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study were analyzed. Researchers examined whether changes (median follow-up: 9 years) in the intake of total dairy and dairy types (in 100 g/1000 kcal total energy intake) were associated with changes in body-mass-index-standard-deviation-score; fat mass index; fat-free mass index over time.
  • The results showed an individual increase in total dairy intake was slightly but significantly associated with an increase in body-mass-index-standard-deviation-score, fat mass index, and fat-free mass index after adjustment for potential confounder. Analyses for liquid dairy and low-sugar dairy intake showed similar results to total dairy intake. Both processing method and fat content showed no association with body composition in our analyses.
  • Increases in total dairy, liquid dairy and low-sugar dairy intake showed small but significant increases in BMI and concomitant increases in fat mass and lean mass. However, the observed changes were too small to expect biological or physiological meaningful effects. Overall, these results showed that policies to promote dairy intake in childhood are to be welcomed, as no negative effects on body composition are expected, while the intake of important nutrients for growth is ensured. The type of dairy does not seem to matter.


Dairy product consumption reduces cardiovascular mortality: results after 8 year follow-up of ELSA-Brasil.
Silva FM, Giatti L, Diniz MFHS, Brant LCC, Barreto SM. Eur J Nutr. 2021 Oct 9.

  • The research on dairy intake and cardiovascular mortality are currently inclusive.
  • The purpose of this study was to investigate whether the consumption of dairy products and their subgroups is associated with the risk of death from cardiovascular disease (CVD) after 8-year follow-up, and verify if dairy products predict changes in high-sensitivity C-reactive protein (hs-CRP) between two follow-up visits of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).
  • This was a prospective study with 6671 participants who did not have CVD at baseline. Consumption in grams/day of total dairy, full-fat and low-fat dairy, fermented dairy, and milk was obtained through a food frequency questionnaire and categorized into sex-specific quartiles.
  • After adjustments, individuals in the 3rd and 4th quartiles of total dairy consumption presented, respectively, 62% and 64% lower hazards of death from CVD compared to the 1st quartile. Also, participants in the 4th quartile of milk consumption had 66% lower hazard to die from CVD, but only the 2nd quartile of full-fat dairy consumption indicated a lower hazard to die from CVD (70%). No association was observed between low-fat or fermented dairy products and cardiovascular mortality. Consumption of total dairy and their subgroups did not predict changes in hs-CRP levels after 4-year follow-up.
  • In conclusion, the results suggest beneficial effects of total dairy and milk, but only low-to-moderate full-fat dairy consumption, on the risk of death from CVD. Assuming true effects, public policies should encourage the consumption of dairy products, especially milk.


Changes in dairy product consumption and subsequent type 2 diabetes among individuals with prediabetes: Tehran Lipid and Glucose Study.
Yuzbashian E, Asghari G, Mirmiran P, Chan CB, Azizi F. Nutr J. 2021 Oct 29;20(1):88.

  • People with prediabetes can postpone or even reverse progression to type 2 diabetes (T2D) by making dietary changes. This study aimed to examine the association of changes in consumption of total and specific types of dairy products with the subsequent risk of incident T2D among individuals with prediabetes.
  • This cohort study included 639 individuals (mean age 47 years) of the Tehran Lipid and Glucose Study (TLGS) who had prediabetes at baseline.
  • Researchers assessed 3-year changes in the consumption of dairy products using a food frequency questionnaire.
  • After almost 9 years of follow-up, the incidence of T2D was 25.2%. Compared with individuals whose intake remained relatively stable over 3 years, those who decreased consumption of total dairy (> 0.5 servings/day) had a higher T2D risk (OR = 1.56).
  • Increasing low-fat dairy consumption by 0.50 serving/d was associated with a lower risk of T2D (OR = 0.56) compared with stable consumption. Those who increased consumption of low-fat milk (OR = 0.59) and low-fat yogurt (OR = 0.55) had a lower risk of T2D than those who were relatively stable in their consumption. Replacing low-fat milk and yogurt with regular cheese was associated with 66 and 47% higher risk of T2D, respectively.
  • In conclusion in individuals with prediabetes, increasing consumption of low-fat dairy, low-fat milk, and low-fat yogurt had reduced risk of subsequent T2D. These data suggest a role of low-fat dairy products in the prevention of T2D among prediabetes patients.

Dairy intake and the risk of pancreatic cancer: the JACC Study and meta-analysis of prospective cohort studies. Arafa A, Eshak ES, Dong JY, Shirai K, Muraki I, Iso H, Tamakoshi A; JACC Study Group. Br J Nutr. 2021 Oct 20:1-27.

  • Dairy intake has been suggested to reduce the risk of gastrointestinal cancers. This study investigated the association between dairy intake and the risk of pancreatic cancer (PAC) using a prospective cohort study and meta-analysis of prospective cohort studies.
  • The study included 59,774 people aged 40-79 years from the Japan Collaborative Cohort Study (JACC Study).
  • In the JACC study, the highest versus no intakes of milk, cheese, and yogurt were not associated with the reduced risk of PAC after a median follow-up of 13.4 years: results did not significantly change in the meta-analysis: for milk, for cheese, and for yogurt. The meta-analysis showed no signs of publication bias or heterogeneity across studies.
  • To conclude, consumption of milk, cheese, and yogurt was not associated with the risk of PAC either in the JACC study or the meta-analysis.

Whole-fat dairy products do not adversely affect adiposity or cardiometabolic risk factors in children in the Milky Way Study: a double-blind randomized controlled pilot study. Nicholl A, Deering KE, Evelegh K, Lyons-Wall P, Lawrence D, Mori TA, Kratz M, O’Sullivan TA. Am J Clin Nutr. 2021 Oct 11:nqab288.

  • Limited evidence supports the common public health guideline that children >2 years of age should consume dairy with reduced fat content.
  • Researchers aimed to investigate the effects of whole-fat compared with reduced-fat dairy intake on measures of adiposity and biomarkers of cardiometabolic risk in healthy 4- to 6-year-old children.
  • The Milky Way Study enrolled 49 children (mean age of 5 years old) who were habitual consumers of whole-fat dairy, then randomly assigned them in a double-blind fashion to remain on whole-fat dairy or switch their dairy consumption to reduced-fat products for 3 months. Primary endpoints included measures of adiposity, body composition, blood pressure, fasting serum lipids, blood glucose, glycated hemoglobin (HbA1c), and C-reactive protein (CRP) and were assessed at baseline and study end.
  • The results showed that dairy fat intake was reduced by about 13 g/d in the reduced-fat compared with the whole-fat dairy group, whereas dietary energy intakes remained similar. The researchers found no significant differential changes between dairy groups in any measure of adiposity, body composition, blood pressure, or fasting serum lipids, glucose, HbA1c, and CRP.
  • In conclusion, these results suggest that although changing from whole-fat to reduced-fat dairy products does reduce dairy fat intake, it does not result in changes to markers of adiposity or cardiometabolic disease risk in healthy children.

Inverse associations between food diversity in the 2nd year of life and allergic diseases. Stampfli M, Frei R, Divaret-Chauveau A, Schmausser-Hechfellner E, Roduit C, et al.; PASTURE study group. Ann Allergy Asthma Immunol. 2021 Oct 11:S1081-1206(21)01154-6.

  • The influence of diet in early childhood on later allergic diseases is currently a highly debated research topic. We and others have suggested that an increased diet diversity in the first year of life has a protective effect on the development of allergic diseases.
  • The aim of this follow-up study was to investigate associations between diet in the 2nd year of life and later allergic diseases.
  • 1014 children from rural areas in 5 European countries (PASTURE birth cohort) were included. Information on feeding practices in their 2nd year of life and allergic diseases were collected up to age 6 years. Multivariate logistic regressions were performed, with different models considering reverse causality, such as excluding children with a positive sensitization to egg and/or cow’s milk at the age of 1 year.
  • An increased food diversity score during the 2nd year of life, was negatively associated with the development of asthma. Consumption of dairy products and eggs in the 2nd year of life showed an inverse association with reported allergic outcomes. Consumption of butter was strongly associated with protection against asthma and food sensitization. Yogurt and cow’s milk were inversely associated against food allergy (OR for yogurt 0.05; OR for cow’s milk 0.31).
  • In conclusion, increased food diversity in the 2nd year of life is inversely associated with the development of asthma, and consumption of dairy products might have a protective effect on allergic diseases.

Innovation, Economics, and Dairy Alternatives

Integrating diverse data sources to predict disease risk in dairy cattle – a machine learning approach. Lasser J, Matzhold C, Egger-Danner C, Fuerst-Waltl B, Steininger F, Wittek T, Klimek P. J Anim Sci. 2021 Oct 18:skab294.

  • Livestock farming is currently undergoing a digital revolution and becoming increasingly data-driven. Yet, such data often reside in disconnected silos making it impossible to leverage their full potential to improve animal well-being.
  • Here, researchers introduce a precision livestock farming approach, bringing together information streams from a variety of life domains of dairy cattle to study whether including more and diverse data sources improves the quality of predictions for eight diseases and whether using more complex prediction algorithms can, to some extent, compensate for less diverse data.
  • Using three machine learning approaches of varying complexity (from logistic regression to gradient boosted trees) trained on data from 5,828 animals in 165 herds in Austria, researchers show that the prediction of lameness, acute and chronic mastitis, anestrus, ovarian cysts, metritis, ketosis (hyperketonemia) and periparturient hypocalcemia (milk fever) from routinely available data gives encouraging results.
  • An analysis of the importance of individual variables to prediction performance shows that disease in dairy cattle is a product of the complex interplay between a multitude of life domains such as housing, nutrition or climate, that including more and diverse data sources increases prediction performance and that the re-use of existing data can create actionable information for preventive interventions.
  • These findings pave the way towards data-driven point-of-care interventions and demonstrate the added value of integrating all available data in the dairy industry to improve animal well-being and reduce disease risk.

Organic versus Conventional Raw Cow Milk as Material for Processing. Brodziak A, Wajs J, Zuba-Ciszewska M, Król J, Stobiecka M, Jańczuk A. Animals (Basel). 2021 Sep 22;11(10):2760.

  • Milk, as one of the basic raw materials of animal origin, must be of adequate hygienic and physicochemical quality for processing.
  • The aim of the article was to compare the quality of raw milk from three production systems, intensive, traditional (together referred to as conventional), and organic, as material for processing, as well as the quality of products made from it. Particular attention was focused on hygienic quality (somatic cell count and total bacterial count), physical characteristics (acidity), basic nutritional value (content of dry matter, total protein, casein, fat, and lactose), content of health-promoting substances (whey proteins, fatty acids, vitamins, and minerals), and technological parameters (rennet clotting time, heat stability, and protein-to-fat ratio).
  • Research assessing the quality of organic milk and dairy products is significantly less extensive (if available at all) than for milk from conventional production (intensive and traditional). The available reports indicate that raw milk from organic farms is more valuable, especially in terms of the content of health-promoting compounds, including vitamins, fatty acids, whey proteins, and minerals. This applies to organic dairy products as well, mainly cheese and yoghurt. This is explained by the fact that organic farming requires that animals are kept in the pasture.
  • However, the hygienic quality of the raw milk, and often the products as well, raises some concerns; for this reason, organic milk producers should be supported in this regard, e.g., through consultancy and training in Good Hygienic Practices. Importantly, milk production in the traditional and organic systems is in line with the concept of the European Green Deal.

Data Governance in the Dairy Industry. Cue R, Doornink M, George R, Griffiths B, Jorgensen MW, Rogers R, Saha A, Taysom K, Cabrera VE, Wangen SR, Fadul-Pacheco L. Animals (Basel). 2021 Oct 15;11(10):2981.

  • Data governance is a growing concern in the dairy farm industry because of the lack of legal regulation.
  • In this commentary paper, researchers discuss the status quo of the available legislation and codes, as well as some possible solutions. There are currently four codes of practice that address agriculture data worldwide, and their objectives are similar:
    • raise awareness of diverse data challenges such as data sharing and data privacy,
    • provide data security, and
    • illustrate the importance of the transparency of terms and conditions of data sharing contracts.
  • However, all these codes are voluntary, which limits their adoption. We propose a Farmers Bill of Rights for the dairy data ecosystem to address some key components around data ownership and transparency in data sharing.
  • The researchers hope to start the discussion to create a balanced environment to promote equity within the data economy, encourage proper data stewardship, and to foster trust and harmony between the industry companies and the farmers when it comes to sharing data.

Life cycle assessment (LCA) of bio-based packaging solutions for extended shelf-life (ESL) milk. Cappiello G, Aversa C, Genovesi A, Barletta M. Environ Sci Pollut Res Int. 2021 Oct 25:1-12.

  • The dairy market is one of the most important sectors worldwide, and milk packaging contributes to over one-third of the global dairy packaging demand. The end of life of the disposable packages is a critical stage of their life cycle, as demonstrated by the fact that disposable bottles are one of the litter items that are most found on beach shores.
  • The aim of this paper is to analyze the performance of bioplastic bottles compared to other alternatives currently in use in the milk packaging sector, using the life cycle assessment (LCA) methodology.
  • Bio-compostable plastic can be a powerful means to create a circular economy for disposable items. A PLA-based bottle is compared to a PET bottle, a HDPE bottle, a multilayer carton, and a glass bottle. In the analysis, also secondary and tertiary packaging is included. The functional unit chosen is “the packaging needed to contain 1 L of ESL milk and to guarantee a shelf life of 30 days”. Two sensitivity analyses are also performed in order to assess the influence of the end-of-life stage on the total impact.
  • The results show that, in accordance with the assumptions of an ideal scenario, bioplastic system has a better performance than fossil-based systems and multilayer carton in the categories of climate change, ozone depletion, human toxicity, freshwater eutrophication, particular matter, and land use. The recycling scenario strongly changes the impact of the glass packaging system in the considered categories.

Perspective: Unpacking the Wicked Challenges for Alternative Proteins in the United States: Can Highly Processed Plant-Based and Cell-Cultured Food and Beverage Products Support Healthy and Sustainable Diets and Food Systems? Kraak VI. Adv Nutr. 2021 Oct 18:nmab113.

  • Over the past decade, a plethora of alternative protein (AP) products has entered the US food system as plant-based food and beverage products. These AP products, which include plant-based meat and dairy alternatives and cell-cultured meat and seafood products, are being developed for the marketplace to simulate the appearance, texture, taste, and flavor and nutritional profiles of animal products.
  • The new generation of AP plant-based and cell-cultured food and beverage products are part of a market-driven narrative that has embraced technology to address future human health, environmental, ethical, and planetary health challenges.
  • This perspective article synthesizes evidence about the benefits of adopting minimally processed plant-based diets that support sustainable food systems and human and planetary health. Thereafter, it examines 4 wicked challenges related to AP products in the US context that include:
    1. a confusing marketing landscape for the public;
    2. diverse views and varying acceptance among consumers about the health and environmental benefits of these products;
    3. inadequate education and labeling provided by federal agencies to enable consumers to understand how these may support healthy sustainable diets; and
    4. slow federal policy and regulatory actions to address the range of AP products and provide industry guidance.
  • The article concludes with suggested policies and actions for government agencies and food system actors to address these challenges. Future research and actions are needed to balance the human health, equity, animal welfare, and economic viability goals and to clarify how AP products may support safe, healthy, sustainable diets and food systems.

The role of plant-based alternative foods in sustainable and healthy food systems: Consumption trends in the UK. Alae-Carew C, Green R, Stewart C, Cook B, Dangour AD, Scheelbeek PFD. Sci Total Environ. 2021 Oct 18:151041.

  • A global transformation towards sustainable food systems is crucial for delivering on climate change mitigation targets worldwide. In high- and middle-income settings, plant-based meat and dairy alternatives present potential substitutes for animal sourced foods, and a pathway to transition to more sustainable diets.
  • Researchers examined plant-based alternative foods (PBAF) consumption trends in the UK by analyzing repeated cross-sectional food consumption data from the National Diet and Nutrition Survey 2008-2019.
  • Dietary data for 15,655 individuals aged 1.5 years and over were analyzed to assess aggregate change in intake of PBAF and six other food groups that play a role in transformative dietary change. Characteristics associated with consumption of PBAF were explored using logistic regression, and consumption patterns in high and low meat consumers were explored by examining intake of potential animal product substitute food groups.
  • The proportion of individuals reporting consumption of any PBAFs increased from 6.7% in 2008-2011, to 13.1% in 2017-2019. Compared to 2008-2011 PBAF consumption rose by 115% in 2017-2019. Females were 46% more likely than males to report consumption of PBAF.
  • Millennials (age 24-39 years) were the most likely generation to report PBAF consumption compared to generation Z (age 11-23 years) and traditionalists (age 75+ years), as were individuals of the highest income tertile. Among “low meat consumers”, PBAF consumption was on average higher than “high meat consumers” (18.6 g versus 4.8 g PBAF per day).
  • These results support the hypothesis of a pivotal role of PBAF in the transition towards sustainable food systems in the UK, by demonstrating they are becoming increasingly popular among UK consumers. This highlights the urgent need to assess in detail the environmental and health impacts of large scale and population-wide consumption of PBAF in comparison to their animal-based equivalents.