Here are some research offerings from February! The Bulletin delivers a brief synopsis of the most current Human, Animal, and Environmental dairy research that is going on in the World, and also that which is of special interest to California dairy producers and consumers alike.

If you would like to peruse the most pertinent dairy research from months past, then visit the Dairy Research Bulletin Archive


Selected Publications on Animal Health, Food Safety, and Sustainability

U.S. farmers’ opinions on the use of nontraditional water sources for agricultural activities. Suri MR, Dery JL, Pérodin J, Brassill N, He X, Ammons S, Gerdes ME, Rock C, Goldstein RER. Environ Res. 2019 Feb 22;172:345-357. 

  • Water is a key resource for agricultural production in the United States. Due to projected changes in water availability across the country, long-term sustainability of agricultural production may rely on finding alternatives to traditional water sources.
  • The aim of this study was to assess farmers’ opinions on the use of nontraditional water sources (e.g., agricultural runoff, treated wastewater, recycled water, produced water, untreated surface water, and brackish surface and groundwater) for agricultural activities. A survey was distributed to farmers (n = 746) in the Mid-Atlantic and Southwest regions of the United States (U.S.) about water availability and nontraditional irrigation water perceptions.
  • Of farmers surveyed, 80% (431/543) considered the use of nontraditional water sources to be at least moderately important and 61% (444/727) would use nontraditional water if given the option.
  • Each of the following factors individually increased the likelihood that a farmer considered nontraditional water very important for agriculture:
    • Farmers who lived in the Southwest region compared to the Mid-Atlantic
    • Farmers who were concerned about water availability compared with those who were not
    • Farmers with a graduate or professional degree compared to those with less education
    • Farmers with access to nontraditional water
    • Farmers with some knowledge of nontraditional water compared to those with no reported knowledge
  • Water quality, food safety and health risks were the main concerns regarding nontraditional water use across both regions. Projects focused on nontraditional water use in agriculture should be regionally tailored as this data showed significant differences between farmers in two distinct U.S. regions.

Calf care personnel on dairy farms and their educational opportunities. Sischo WM, Moore DA, Pereira R, Warnick L, Moore DL, Vanegas J, Kurtz S, Heaton K, Kinder D, Siler J, Davis MA. J Dairy Sci. 2019 Feb 13. pii: S0022-0302(19)30146-8. 

  • As dairy herd sizes become larger and the organization of the business more complex, targeting communication and education to enhance animal care becomes more difficult.
  • The purpose of this study was to describe selected demographics of calf care employees on large (>500 animals) and small (<501 animals) dairy farms that raise their own calves. Two to 8 individuals per farm involved with calf care, including owners, veterinarians, and calf managers, feeders, and treaters, were interviewed in either English or Spanish.
  • Interviews were conducted in person on 53 dairy farms located in Arizona, Idaho, New York, Oregon, and Washington State. A total of 224 individuals were interviewed across 8 job titles.
  • Almost 30% of owners and over 40% of veterinarians interviewed were over 50 yr of age, whereas over 40% of the calf managers, feeders, and treaters were under 30 yr of age.
  • Seventy-three percent of feeders and 72% of treaters spoke Spanish at home. For languages in which interviewees were comfortable speaking, more than 30% of owners and 33% of veterinarians were comfortable communicating in Spanish. For calf-care employees, 60% of calf managers, 42% of feeders, and 38% of treaters were bilingual (English and Spanish), but most (72%) preferred to be interviewed in Spanish.
  • The level of education varied by job title for those interviewed, but most of the calf care team had high school or less education. However, some diversity was observed in educational background within job title with almost 38% of the calf managers having at least some college education.
  • The majority of feeders (88%) and treaters (83%) reported being trained by another employee and 66 and 58%, respectively, had not received any continuing education in the previous year.
  • With the amount of diversity seen on these farms, understanding employees’ educational backgrounds, language, and generational differences may be valuable when developing training for new procedures for animal health or other aspects of animal care.

Small-scale and backyard livestock owners needs assessment in the western United States. Pires AFA, Peterson A, Baron JN, Adams R, Martínez-López B, Moore D.PLoS One. 2019 Feb 14;14(2):e0212372. 

  • The number of small-scale and backyard livestock and poultry owners in urban and peri-urban areas has increased greatly over the last 10 years in the U.S. However, these animal owners may live in areas without access to livestock and/or poultry veterinary care.
  • The purpose of this study was to identify potential veterinary service needs of these animal owners in the western US, assess their use of management and husbandry practices with regards to disease prevention, and assess their attitudes about animal health and food safety.
  • A semi-structured survey was made available to small-scale and backyard livestock and poultry owners in Washington State, California, Colorado and Oregon. The survey instrument included questions about types of animals reared, uses of the animals, veterinary services and information-seeking behaviors of owners, attitudes on animal health and food safety, and management practices.
  • Four hundred thirty-five individuals completed at least some portion of the survey. Most described themselves as living in rural areas (76%). Most (86%) owned chickens, 53% owned small ruminants, and 31% owned cattle. About 74% of respondents utilized their animals’ products for their own consumption but 48% sold animal products (primarily through internet sales (35%) or farmers’ markets (25%)).
  • Overwhelmingly, respondents gained information about animal health (82%) and animal treatment procedures (71%) from the internet. 43% of respondents had not sought animal health care in last 12 months.
  • Livestock species type (cattle, small ruminants and swine), and use (personal or commercial) were associated with implementation of different biosecurity practices.
  • The results of this survey highlight some of the needs of these animal owners for veterinary care and information which are location- and species-specific. Veterinary care for these small-scale and backyard animals is vital to the health and welfare of the animals as well as for identification of zoonoses and assurance of the food safety of animal products.

Improvement of the antimicrobial activity of lactic acid bacteria in combination with berries/fruits and dairy industry by-products. Bartkiene E, Lele V, Sakiene V, Zavistanaviciute P, Ruzauskas M, Bernatoniene J, Jakstas V, Viskelis P, Zadeike D, Juodeikiene G.J Sci Food Agric. 2019 Feb 4. 

  • By-products from fruit and dairy industries are important environmental issues in many countries.
  • In this study the concept of the improvement of antimicrobial activity of lactic acid bacteria in combination with fruit (raspberries, blackcurrants, apples, rowanberries) and dairy industry by-products was analyzed.
  • Antimicrobial activities of the fruit by-products and lactic acid bacteria (thirteen lactic acid bacteria strains were estimated against fifteen pathogenic strains) were evaluated, while whey substrate for the selected and the highest antimicrobial activities showing lactic acid bacteria cultivation was used.
  • The broadest spectrum of pathogenic bacteria inhibition was shown by lyophilized blackcurrant and apple by-products, which inhibited 13 and 12 pathogenic strains of the 15 analyzed, respectively. The fruit by-products’ antimicrobial activity can be enhanced in combination with certain lactobacillus strains.
  • Lactic acid bacteria, fruit and dairy industry by-products can be used for antimicrobial products preparation, as the combination of compounds from the different origin showed higher antimicrobial properties.

The Planning, Implementation, and Evaluation of California’s Inaugural Food Waste Prevention Week. Gosliner W, Delaney T, Caldwell S, Lee JM, Billups N, Floor S. J Public Health Manag Pract. 2019 Feb 14.

  • Preventing food waste can divert food from landfills to feed people, combat climate change, preserve natural resources, and save money.
  • In February 2017, the Nutrition Policy Institute and the Public Health Alliance of Southern California initiated a multisector collaboration among California state agencies to raise awareness about food waste.
  • After development and distribution of a Communications Guide, Food Waste Prevention Week was launched successfully in March 2018, with official support from California’s Governor, Secretary of Agriculture, Superintendent of Public Instruction, and other leaders.
  • The multiagency shared messaging campaign was estimated to reach millions, based on unique page views via social and traditional media. In a follow-up survey, partners expressed satisfaction with Food Waste Prevention Week and interest in participating in future efforts.
  • Organizing leaders across multiple sectors to raise awareness about food waste is possible; such efforts can contribute to driving behavioral and structural changes to reduce food waste.


Selected Articles on Dairy Intake and Human Health

Chocolate Milk versus carbohydrate supplements in adolescent athletes: a field based study. Born KA, Dooley EE, Cheshire PA, McGill LE, Cosgrove JM, Ivy JL, Bartholomew JB. J Int Soc Sports Nutr. 2019 Feb 12;16(1):6.

  • One approach to improve the response to resistance training is the use of post-exercise nutritional interventions; with carbohydrate-protein beverages garnering significant interest. Much of the work has been applied to endurance training, where carbohydrate-protein supplements have been shown to be the superior post-exercise recovery compared to a carbohydrate beverage alone.
  • The purpose of this study is to translate laboratory-based research on beverage-based supplements to a naturalistic, field setting in adolescent athletes.
  • The researchers tested the effects of two commercially-available drinks on strength in a field-based setting with both male and female high school athletes completing a summer training program. Participants were randomly-assigned to receive either chocolate milk or a carbohydrate beverage immediately post-exercise.
  • Measures included a composite strength score (bench press + squat). Participants completed 1 week of pre- and post-testing, and 4 days per week of strength and conditioning training for 5 weeks. One hundred and three high school athletes completed the study.
  • There was a significant interaction of composite strength score between groups. The chocolate milk group had significantly greater improvements (12.3% increase) in composite strength from pre- to post-test than the carbohydrate group (2.7% increase).
  • This is the first study comparing the impact of chocolate milk and carbohydrate beverage on athletic outcomes in an adolescent population in a field-based environment. Chocolate milk had a more positive effect on strength development and should be considered an appropriate post-exercise recovery supplement for adolescents.

Effect of dairy and non-dairy snacks on postprandial blood glucose regulation in 9-14 year old children. Gheller BJF, Gheller M, Li A, Nunes F, Anini Y, Glanville T, Bellissimo N, Hamilton JK, Anderson GH, Luhovyy BL. Appl Physiol Nutr Metab. 2019 Feb 22.

  • In adults, dairy consumption improves short-term blood glucose regulation. It is unknown whether these short-term benefits extend to children of different weight statuses.
  • The objective of this study was to investigate the effect of a dairy and non-dairy snack in both normal weight (NW) and overweight/obese (OW/OB) children on blood glucose regulation and food intake.
  • In a repeated measures crossover design, 11 NW and 7 OW/OB children (age: 9-14y), consumed, in random order, a dairy (Greek yogurt, 198.9g, 171kcal, 0g fat, 17g protein) or non-dairy (mini sandwich type cookies, 37.5g, 175kcal, 7.5g fat, 1.3g protein) snack containing 25g of available carbohydrates.
  • Food intake did not differ between snacks. Mean blood glucose was lower and insulin higher in the 120 min after consuming the dairy snack. Insulin secretion was not different between snacks. The increase in insulin was explained by reduced hepatic insulin extraction.
  • Consumption of the dairy snack also increased mean GLP-1 concentrations (P<0.001). In conclusion, consumption of a dairy snack by NW and OW/OB children results in reduced postprandial blood glucose concentrations and elevated circulating insulin compared to a non-dairy snack possibly due to delayed hepatic insulin extraction.

Short sleep and low milk intake are associated with obesity in a community of school aged children from Argentina. Orden AB, Lamarque MS, Chan D, Mayer MA.Am J Hum Biol. 2019 Feb 19:e23224.

  • Understanding the factors related to obesity during childhood allows for improved preventive actions specifically adapted to particular communities.
  • The purpose of this study was to identify individual and familiar factors related to obesity in children.
  • A cross-sectional study was conducted in an urban community in Argentina during the years 2015-2016. Weight and height were measured on a probabilistic sample of 1366 schoolchildren aged 6 to 12 years. Data were analyzed using multivariate and logistic regression models. Independent variables corresponded to four domains: anthropometric, socioeconomic and demographic, nutritional, and energy balance.
  • Twenty percent of children were categorized as overweight and 12.2% were obese. These variables were negatively associated with overweight and obesity: hours of sleep, physical activity, and daily milk intake.
  • Like physical activity, the promotion of milk and dairy intake, as well as sleep, may have a major role in obesity reduction because of their protective effects in this community.

Vitamin D-supplemented yogurt drink reduces Candida infections in a pediatric intensive care unit: a randomised, placebo-controlled clinical trial. Xie J, Zhu L, Zhu T, Jian Y, Ding Y, Zhou M, Feng X. J Hum Nutr Diet. 2019 Feb 18.

  • The prevalence of Candida infections in pediatric intensive care units (PICUs) has dramatically increased as a result of resistance to conventional anti-fungal treatments.
  • Because vitamin D has been shown to exhibit fungicidal activity against Candida infection in an in vitro antimicrobial screening, the researchers aimed to investigate the effect of vitamin D on Candida infections in the PICU.
  • Four hundred sixteen eligible children aged between 12 months to 5 years old admitted to the PICU, who were on broad-spectrum antibiotic therapy, participated in the study. Patients were randomly assigned to two study groups, receiving a plain yogurt drink (placebo group) or supplemented with 300 IU day-1 vitamin.
  • The primary outcome was defined as the incidences of Candida colonisation (Candida isolated from rectal swab) 14 days after enrollment. Secondary outcome measures were Candida growth in blood (candidaemia) and urine (candiduria).
  • The prevalence of candiduria as well as candidaemia was significantly lower in the Vitamin D-treated group (26 cases) than in the placebo group (62 cases). The mean length of PICU stay was lowered in the Vitamin D group [~11.8 days] compared to the placebo group [~15.2 days], whereas cases of patient death were similar between the two groups.
  • Supplementation of vitamin D effectively reduces infections of Candida in children who were critically ill and on broad-spectrum antibiotic treatment.

Meals with Similar Fat Content from Different Dairy Products Induce Different Postprandial Triglyceride Responses in Healthy Adults: A Randomized Controlled Cross-Over Trial. Hansson P, Holven KB, Øyri LKL, Brekke HK, Biong AS, Gjevestad GO, Raza GS, Herzig KH, Thoresen M, Ulven SM.J Nutr. 2019 Feb 13. 

  • Postprandial lipemia is a risk factor for cardiovascular disease. Dairy products differ in nutrient content and food matrix, and little is known about how different dairy products affect postprandial triglyceride concentrations.
  • The researchers investigated the effect of meals with similar amounts of fat from different dairy products on postprandial triglyceride concentrations over 6 hours in healthy adults.
  • A randomized controlled cross-over study was performed on 47 subjects, with average age of 32 years and body mass index of 23.6 kg/m2. Meals included 1 of butter, cheese, whipped cream, or sour cream, corresponding to 45 g of fat (approximately 60 energy%). Serum concentrations of several lipids and hormones were measured over 2, 4 and 6 hours.
  • Sour cream induced a 61% larger total triglyceride concentration over 6 hours compared to whipped cream, a 53% larger amount compared to butter, and a 23% larger amount compared to cheese. No differences in 6-hour triglycerides were observed between the other meals.
  • Intake of sour cream induced a larger total HDL cholesterol concentration over 6 hours compared to cheese.
  • Intake of cheese induced a 124% larger 6-hour insulin concentration compared to butter.
  • High-fat meals containing similar amount of fat from different dairy products induce different postprandial effects on serum triglycerides, HDL cholesterol, and insulin in healthy adults.

Dairy Product Intake and Risk of Type 2 Diabetes in EPIC-InterAct: A Mendelian Randomization Study. Vissers LET, Sluijs I, van der Schouw YT, et al.  Diabetes Care. 2019 Feb 6. pii: dc182034.

  • Higher intake of dairy products has been associated with a lower risk of diabetes in a meta-analysis of observational studies. Particularly yogurt and cheese intake were associated with lower diabetes risk, whereas milk intake was not, with substantial heterogeneity for most dairy products.
  • Protective components of dairy products may be whey-proteins, odd-chain fatty acids, and the high nutrient density of dairy. Also, interactions within the dairy food matrix may modify the metabolic effects of dairy consumption.
  • The study objective was to estimate the causal association between intake of dairy products and incident type 2 diabetes.
  • In instrumental variable analysis, lactase persistence -associated milk intake was not associated with diabetes. Lactase persistence was associated with milk intake but not with intake of other dairy products.
  • This Mendelian Randomization study does not suggest that milk intake is associated with diabetes, which is consistent with previous observational and genetic associations.

Antioxidant properties of Milk and dairy products: a comprehensive review of the current knowledge. Khan IT, Nadeem M, Imran M, Ullah R, Ajmal M, Jaspal MH. Lipids Health Dis. 2019 Feb 4;18(1):41.

  • Milk and dairy products are integral part of human nutrition and they are considered as the carriers of higher biological value proteins, calcium, essential fatty acids, amino acids, fat, water soluble vitamins and several bioactive compounds that are highly significant for several biochemical and physiological functions.
  • In recent years, foods containing natural antioxidants are becoming popular all over the world as antioxidants can neutralize and scavenge the free radicals and their harmful effects, which are continuously produced in the biological body.
  • Uncontrolled free radicals activity can lead to oxidative stresses, which have been implicated in breakdown of vital biochemical compounds such as lipids, protein, DNA which may lead to diabetes, accelerated ageing, carcinogenesis and cardiovascular diseases.
  • Antioxidant capacity of milk and milk products is mainly due to sulfur containing amino acids, such as cysteine, phosphate, vitamins A, E, carotenoids, zinc, selenium, enzyme systems, superoxide dismutase, catalase, glutathione peroxidase, milk oligosaccharides and peptides that are produced during fermentation and cheese ripening.
  • Antioxidant activity of milk and dairy products can be enhanced by phytochemicals supplementation while fermented dairy products have been reported contained higher antioxidant capacity as compared to the non-fermented dairy products.
  • This review summarizes and describes the nutritional and antioxidant capacity of milk and dairy products.