The 50 most-cited articles in Journal of Dairy Science, 2024

An economic simulation was carried out over 183 milk-producing countries to estimate the global economic impacts of 12 dairy cattle diseases and health conditions: mastitis (subclinical and clinical), lameness, paratuberculosis (Johne's disease), displaced abomasum, dystocia, metritis, milk fever, ovarian cysts, retained placenta, and ketosis (subclinical and clinical). Estimates of disease impacts on milk yield, fertility, and culling were collected from the literature, standardized, meta-analyzed using a variety of methods ranging from simple averaging to random-effects models, and adjusted for comorbidities to prevent overestimation. These comorbidity-adjusted disease impacts were then combined with a set of country-level estimates for lactational incidence or prevalence or both, herd characteristics, and price estimates within a series of Monte Carlo simulations that estimated and valued the economic losses due to these diseases. It was estimated that total annual global losses are US$65 billion (B). Subclinical ketosis, clinical mastitis, and subclinical mastitis were the…

Methane, both enteric and from manure management, is the most important greenhouse gas from ruminant livestock, and its mitigation can deliver substantial decreases in the carbon footprint of animal products and potentially contribute to climate change mitigation. Although choices may be limited, certain feeding-related practices can substantially decrease livestock enteric CH 4 emission. These practices can be generally classified into 2 categories: diet manipulation and feed additives. Within the first category, selection of forages and increasing forage digestibility are likely to decrease enteric CH 4 emission, but the size of the effect, relative to current forage practices in the United States dairy industry, is likely to be minimal to moderate. An opportunity also exists to decrease enteric CH 4 emissions by increasing dietary starch concentration, but interventions have to be weighed against potential decreases in milk fat yield and farm profitability. A similar conclusion can be made about dietary lipids and oilseeds, which are proven to decrease CH 4 emission but can also…

Yogurt, as a globally prevalent fermented dairy product, is renowned for its substantial nutritional value and a myriad of health benefits, particularly pertaining to the digestive system. This narrative review elucidates the latest advancements in yogurt development from 2019 to 2024, addressing aspects of microbiological safety, quality, functionality, sensory evaluation, and consumer perceptions across diverse protein sources. The intrinsic quality of yogurt is notably influenced by its primary ingredient, milk, traditionally derived from animals such as cows, goats, and sheep. In recent years, plant-based yogurt (PBY) have emerged as a popular alternative to traditional dairy yogurts, that are made from plant sources and offer similar textures and flavors, catering to those seeking nondairy options. This discussion encompasses the advantages and limitations of various sources and explores methodologies to enhance yogurt quality using these diverse sources. Ensuring the microbiological safety of yogurt is thus paramount to its quality, as it involves both preventing the presence…

The objective was to determine the long-term effect of 3-nitrooxypropanol ( 3-NOP ) on CH 4 emission and milk production characteristics from dairy cows receiving 3-NOP in their diet for a full year, covering all lactation stages of the dairy cows. Sixty-four late-lactation Holstein Friesian cows (34% primiparous) were blocked in pairs, based on expected calving date, parity, and daily milk yield. The experiment started with an adaptation period of 1 week followed by a covariate period of 3 weeks in which all cows received the same basal diet and baseline measurements were performed. Directly after, cows within a block were randomly allocated to 1 of 2 dietary treatments: a diet containing on average 69.8 mg 3-NOP/kg DM (total ration level, corrected for intake of non-supplemented GreenFeed bait) and a diet containing a placebo. Forage composition as well as forage to concentrate ratio altered with lactation stage (i.e., dry period and early, mid, and late lactation). Diets were provided as a total mixed ration and additional bait was fed in GreenFeed units which were used for…

Ketosis is currently regarded as a major metabolic disorder of dairy cows, reflective of the animal's efforts to adapt to energy deficit while transitioning into lactation. Currently viewed as a pathology by some, ketosis is associatively implicated in milk production losses and peripartal health complications that increase the risk of early removal of cows from the herd, thus carrying economic losses for dairy farmers and jeopardizing the sustainability of the dairy industry. Despite decades of intense research in the mitigation of ketosis and its sequelae, our ability to lessen its purported effects remains limited. Moreover, the association of ketosis to reduced milk production and peripartal disease is often erratic and likely mired by concurrent potential confounders. In this review, we discuss the potential reasons for these apparent paradoxes in the light of currently available evidence, with a focus on the limitations of observational research and the necessary steps to unambiguously identify the effects of ketosis on cow health and performance via controlled randomized…

Milk adulteration poses a global concern, with developing countries facing higher risks due to unsatisfactory monitoring systems and policies.Surprisingly, this common issue has often been overlooked in many countries.Contrary to popular belief, adulterants in milk can result in severe health risks, potentially leading to fatal diseases.Detecting and categorizing milk adulteration is crucial for consumer safety and the dairy industry.This research is divided into 2 breakthroughs, destructive and nondestructive methods.In the destructive method, the Lactoscan system was used for qualitative analysis: SNF, density, fat, lactose, conductivity, solids, protein, temperature, and pH level.The research also examines nondistractive hyperspectral imaging (HSI) through HSI Specim Fx-10 (397-1,003 nm; Specim, Spectral Imaging Ltd., Oulu, Finland) analysis to detect various phases of milk adulteration for accurate and user-friendly imagingbased adulterant detection and categorization.Preprocessing involves radiometric correction, image resizing, region of interest selection for feature…

Ruminal acidosis occurs as a continuum of disorders, stemming from ruminal dysbiosis and disorders of metabolism, of varying severity. The condition has a marked temporal dynamic expression, resulting in cases expressing quite different rumen concentrations of VFA, lactic acid, ammonia, and rumen pH over time. Clinical ruminal acidosis is an important condition of cattle and subclinical ruminal acidosis (SRA) is very prevalent in many dairy populations, with estimates between 10% and 26% of cows in early lactation. Estimates of the duration of a case suggest that the lactational incidence of the condition may be as high as 500 cases per 100 cows in the first 100 d of lactation. Historical confusion about the etiology and pathogenesis of ruminal acidosis led to definitions that are not fit for purpose, as acidic ruminal conditions solely characterized by ruminal pH determination at a single point fail to reflect the complexity of the condition. Use of a model based on integrated ruminal measures, including VFA, ammonia, lactic acid, and pH, for evaluating ruminal acidosis is fit for…

There is a need for rigorous and scientifically-based testing standards for existing and new enteric methane mitigation technologies, including antimethanogenic feed additives (AMFA). The current review provides guidelines for conducting and analyzing data from experiments with ruminants intended to test the antimethanogenic and production effects of feed additives. Recommendations include study design and statistical analysis of the data, dietary effects, associative effect of AMFA with other mitigation strategies, appropriate methods for measuring methane emissions, production and physiological responses to AMFA, and their effects on animal health and product quality. Animal experiments should be planned based on clear hypotheses, and experimental designs must be chosen to best answer the scientific questions asked, with pre-experimental power analysis and robust post-experimental statistical analyses being important requisites. Long-term studies for evaluating AMFA are currently lacking and are highly needed. Experimental conditions should be representative of the production…

The diffusion of microplastics in the food supply chain is prompting public concern as their impact on human health is still largely unknown. The aim of this study was to qualitatively and quantitatively characterize microplastics in skim-milk powder samples (n = 16) from different European countries (n = 8) through Fourier-transform infrared microspectroscopy in attenuated total reflectance mode analysis. The present study highlights that the use of hot alkaline digestion has enabled the efficacious identification of microplastics in skim-milk powders used for cheesemaking across European countries. The adopted protocol allowed detection of 29 different types of polymeric matrices for a total of 536 plastic particles. The most abundant microplastics were polypropylene, polyethylene, polystyrene, and polyethylene terephthalate. Microplastics were found in skim-milk powders in 3 different shapes (fiber, sphere, and irregular fragments) and 6 different colors (black, blue, brown, fuchsia, green, and gray). Results demonstrate the presence of microplastics in all skim-milk powder…

Yogurt is popular as a natural and healthy food, but its flavor greatly affects acceptability by consumers. Flavor compounds of yogurt are generally produced by the metabolism of lactose, protein, and fat, and the resulting flavors include carbonyls, acids, esters, alcohols, and so on. Each flavor compound can individually provide the corresponding flavor, or it can be combined with other compounds to form a new flavor. The flavor network is formed among the metabolites of milk components, and acetaldehyde, as the central compound, plays a role in connecting the whole network. The flavor compounds can be affected by many factors, such as the use of different raw milks, ways of homogenization, sterilization, fermentation, postripening, storage condition, and packaging materials, which can affect the overall flavor of yogurt. This paper provides an overview of the volatile flavor compounds in yogurt, the pathways of production of the main flavor compounds during yogurt fermentation, and the factors that influence the flavor of yogurt, including type of raw milk, processing, and…

The aim of this systematic review was to summarize the literature assessing the effects of weaning practices on performance, behavior, and health of dairy calves. Only published, peer-reviewed articles written in English and specifically assessing the effects of weaning treatments on dairy calves were eligible for inclusion. Studies had to include 2 or more treatment groups that addressed at least one of 4 interventions: weaning age (i.e., when milk was fully removed), weaning duration (i.e., number of days from start of milk reduction to when milk was fully removed), weaning criteria (e.g., age vs. intake), or alternative weaning methods (e.g., water dilution). Outcome measures could include starter intake, growth (BW or ADG), behaviors (5 specific sucking behaviors; play behavior; lying behavior; vocalizations; unrewarded visits to an automated milk feeder), and health (mortality rate, diarrhea, and respiratory illness). We conducted 3 targeted searches using Web of Science and PubMed. The articles underwent a 2-step screening process, resulting in a final sample of 44 studies.…

Colostrum is a rich source of nutritional and non-nutritional components and is recognized as essential to transfer passive immunity to newborn calves. Because of the individual and seasonal variability in colostrum yield and composition, maintaining an adequate supply of high-quality colostrum year-round remains a challenge for commercial dairy producers. In this narrative review, we described the individual, seasonal, and herd-level variability of colostrum production and summarized the association between individual animal factors such as parity, sex of the calf, calf birth weight, as well as indicators of the cow's metabolic status and the yield and composition of colostrum. Further, we reviewed the current knowledge on the influence of prepartum nutrition and management strategies on colostrum production. Research on the metabolizable energy and protein supplied in the prepartum diet as well as on the inclusion and source of vitamins, minerals, and feed additives suggests prepartum nutrition influences the yield, quality, and composition of colostrum. Furthermore, the prepartum…

Cow milk, although rich in essential nutrients, is a well-known food allergen that can cause allergic reactions in infants and young children. β-Lactoglobulin accounts for 10% of the total protein in milk and 50% of the whey protein, which has high nutritional value and excellent functional properties but is also the main allergen leading to milk protein allergy. Exploring the mechanism of milk allergy and selecting suitable separation and purification methods to obtain high-purity β-LG is the premise of research on reducing allergenicity. In this review, the research progress in membrane technology, gel filtration chromatography, ion exchange chromatography, affinity chromatography, precipitation, and aqueous 2-phase system separation for the separation and purification of milk β-LG is reviewed in detail to promote the further development of milk β-LG separation and purification methods and provide a new method for the development of hypoallergenic dairy products in the future. Among these methods, ion exchange chromatography and gel chromatography are widely used, precipitation is…

This study evaluates Instagram's efficacy as an educational tool in veterinary sciences, focusing on dairy cow nutrition and management. Using the Instagram account "Stalla Didattica Unibo," established in December 2020, a survey was conducted with 102 respondents, primarily consisting of university students (44.12%). The respondents were divided into 2 major groups: students and the general population, with the latter comprising professionals and others not currently in educational programs. In the overall population, the age group of 25 to 34 yr accounted for 51%, but among students, it was 73.3%. In terms of gender distribution, there was a female majority in the general population (59.8%) and a male majority among students (73.3%). Most responders were from Italy, with Emilia-Romagna contributing significantly. Engagement was measured not only by the length of time participants followed the account but also by active interactions such as likes, comments, and shares. Among the total population, 47.1% had followed the page for over a year, compared with 37.8% of students.…

This publication aims to provide guidelines of the knowledge required and the potential research to be conducted in order to understand the mode of action of antimethanogenic feed additives (AMFA). In the first part of the paper, we classify AMFA into 4 categories according to their mode of action: (1) lowering dihydrogen (H 2 ) production; (2) inhibiting methanogens; (3) promoting alternative H 2 -incorporating pathways; and (4) oxidizing methane (CH 4 ). The second part of the paper presents questions that guide the research to identify the mode of action of an AMFA on the rumen CH 4 production from 5 different perspectives: (1) microbiology; (2) cell and molecular biochemistry; (3) microbial ecology; (4) animal metabolism; and (5) cross-cutting aspects. Recommendations are provided to address various research questions within each perspective, along with examples of how aspects of the mode of action of AMFA have been elucidated before. In summary, this paper offers timely and comprehensive guidelines to better understand and reveal the mode of action of current and emerging AMFA.

Mastitis has a substantial impact on the dairy industry across the world, causing dairy producers to suffer losses due to the reduced quality and quantity of produced milk. A further problem, related to this issue, is the excessive use of antibiotics that leads to the development of resistance in different bacterial strains. The growing consumer awareness oriented toward food safety and rational use of antibiotics has promoted the search for new methods of early identification of cows that may be at risk of developing the disease. Subclinical mastitis does not cause any visible changes to the udder or milk, and therefore it is more difficult to detect than clinical mastitis. The collection of large amounts of data related to milk performance of cows allows using machine learning ( ML ) methods to build models that could be used for classifying cows into healthy and at risk of subclinical mastitis. The data used for the purpose of this study included information from routine milk recording procedures. The data set consisted of 19,856 records of 2,227 Polish Holstein-Friesian cows…

Ketosis, a commonly observed energy metabolism disorder in dairy cows during the peripartal period, is distinguished by increased concentrations of BHB in the blood. This condition has a negative impact on milk production and quality, causing financial losses. An untargeted metabolomics approach was performed on plasma samples from cows between 5 and 7 DIM diagnosed as controls (CON; BHB <1.2 mM, n = 30), subclinically ketotic (SCK; 1.2 < BHB <3.0 mM, n = 30), or clinically ketotic (CK; BHB >3.0 mM, n = 30). Cows were selected from a commercial farm of 214 Holstein cows (average 305-d yield in the previous lactation of 35.42 ± 7.23 kg/d; parity, 2.41 ± 1.12; BCS, 3.1 ± 0.45). All plasma and milk samples (n = 90) were subjected to liquid chromatography-MS-based metabolomic analysis. Statistical analyses were performed using GraphPad Prism 8.0, MetaboAnalyst 4.0, and R version 4.1.3. Compared with the CON group, both SCK and CK groups had greater milk fat, freezing point, and fat-to-protein ratio, as well as lower milk protein, lactose, solids-not-fat, and milk density. Within 21 d…

Noncovalent interactions of 4 selected phenolic acids, including gallic acid (GA), caffeic acid (CA), chlorogenic acid (CGA), and rosmarinic acid (RA) with lactoferrin (LF) were investigated. Compound combined with LF in the binding constant of CA > GA > RA > CGA, driven by van der Waals and hydrogen bonding for GA, and hydrophobic forces for others. Conformation of LF was affected at secondary and ternary structure levels. Molecular docking indicated that GA and CA located in the same site near the iron of the C-lobe, whereas RA and CGA bound to the C2 and N-lobe, respectively. Significantly enhanced antioxidant activity of complexes was found compared with pure LF, as demonstrated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis(2-ethylbenzothiazoline-6-sulfonate) (ABTS), and ferric reducing antioxidant power (FRAP) models. Caffeic acid, CGA, and RA significantly decreased the emulsifying stability index and improved foam ability of LF, and the effect of CA and RA was the most remarkable, respectively.

Scientific knowledge about ruminal biohydrogenation (BH) has improved greatly since this metabolic process was empirically confirmed in 1951. For years, BH had mostly been perceived as a process to be avoided to increase the postruminal flow of UFA from the diet. Two milestones changed this perception and stimulated great interest in BH intermediates themselves: In 1987, the in vitro anticarcinogenic properties of CLA were described, and in 2000, the inhibition of milk fat synthesis by trans-10,cis-12 CLA was confirmed. Since then, numerous BH metabolites have been described in small and large ruminants, and the major deviation from the common BH pathway (i.e., the trans-10 shift) has been reasonably well established. However, there are some less well-characterized alterations, and the comprehensive description of new BH intermediates (e.g., using isotopic tracers) has not been coupled with research on their biological effects. In this regard, the low quality of some published fatty acid profiles may also be limiting the advance of knowledge in BH. Furthermore, although BH seems to…

Milk and dairy products are important in the human diet not only for the macronutrients, such as proteins and fats, that they provide, but also for the supply of essential micronutrients, such as minerals. Minerals are present in milk in soluble form in the aqueous phase and in colloidal form associated with the macronutrients of the milk. These 2 forms affect the nutritional functions of the minerals and their contribution to the technological properties of milk during cheese making. The aim of the present work was to study and compare the detailed mineral profiles of dairy foods (milk, whey, and cheese) obtained from cows, buffaloes, goats, ewes and dromedary camels, and to analyze the recovery in the curd of the individual minerals according to a model cheese-making procedure applied to the milk of these 5 dairy species. The detailed mineral profile of the milk samples was obtained by inductively coupled plasma-optical emission spectroscopy. We divided the 21 minerals identified in the 3 different matrices into essential macro- and microminerals, and environmental microminerals,…

The large-scale recording of traits such as feed efficiency (FE) and methane emissions (ME) for use in genetic improvement programs is complex, costly, and time-consuming. Therefore, heritable traits that can be continuously recorded in dairy herds and are correlated with FE and ME traits could provide useful information for genetic evaluation. Rumination time has been suggested to be associated with FE, methane production (MeP; ME in g/d), and production traits at the phenotypic level. Therefore, the objective of this study was to investigate the genetic relationships among rumination time (RT), FE, methane and production traits using 7,358 records from 656 first-lactation Holstein cows. The estimated heritabilities were moderate for RT (0.45 ± 0.14), MeP (0.36 ± 0.12), milk yield (0.40 ± 0.08), fat yield (0.29 ± 0.06), protein yield (0.32 ± 0.07), and energy-corrected milk (0.28 ± 0.07), but were low and nonsignificant for FE (0.15 ± 0.07), which was defined as the residual of the multiple linear regression of DMI on energy-corrected milk and metabolic body weight. A favorable…

Lactic acid bacteria (LAB) have a long history of safe use in milk fermentation and are generally recognized as health-promoting microorganisms when present in fermented foods. Lactic acid bacteria are also important components of the human intestinal microbiota and are widely used as probiotics. Considering their safe and health-beneficial properties, LAB are considered appropriate vehicles that can be genetically modified for food, industrial and pharmaceutical applications. Here, this review describes (1) the potential opportunities for application of genetically modified LAB strains in dairy fermentation and (2) the various genomic modification tools for LAB strains, such as random mutagenesis, adaptive laboratory evolution, conjugation, homologous recombination, recombineering, and CRISPR (clustered regularly interspaced short palindromic repeat)-Cas (CRISPR-associated protein)-based genome engineering. Finally, this review also discusses the potential future developments of these genomic modification technologies and their applications in dairy fermentations.

Gut microbiota imbalance could lead to various diseases, making it important to optimize the structure of the gut flora in adults. Lactobacillus paracasei ZFM54 is a bacteriocin- and folic acid-producing Lactobacillus strain. Herein, L. paracasei ZFM54 was used as the potentially probiotic bacterium to ferment milk together with a yogurt starter. We optimized the fermentation conditions, and the obtained yogurts were then subjected to volatile and nonvolatile metabolome analysis, showing that L. paracasei ZFM54 can not only improve the acidity, water holding capacity and live lactic acid bacteria counts, but also improve many volatile acid contents and increase some beneficial nonvolatile metabolites, such as N-ethyl glycine and l-lysine, endowing the yogurt with more flavor and better function. The regulatory effects of the co-fermented yogurt on the intestinal microecology of volunteers were investigated by 16S rRNA sequencing and short-chain fatty acid (SCFA) analysis after consuming the yogurt for a 2-wk period, showing a better effect to increase the relative abundance of…

Over the past decade, there has been considerable attention on mitigating enteric methane (CH 4 ) emissions from ruminants through the utilization of antimethanogenic feed additives (AMFA).Administered in small quantities, these additives demonstrate potential for substantial reductions of methanogenesis.Mathematical models play a crucial role in comprehending and predicting the quantitative impact of AMFA on enteric CH 4 emissions across diverse diets and production systems.This study provides a comprehensive overview of methodologies for modeling the impact of AMFA on enteric CH 4 emissions in ruminants, culminating in a set of recommendations for modeling approaches to quantify the impact of AMFA on CH 4 emissions.Key considerations encompass the type of models employed (i.e., empirical models including meta-analyses, machine learning models, and mechanistic models), the modeling objectives, data availability, modeling synergies and trade-offs associated with using AMFA, and model applications for enhanced understanding, prediction, and integration into higher levels of…

Grape pomace (GP) is a byproduct of the viticulture industry and shows promise for feeding dairy cattle as well as reducing enteric methane (CH 4 ) emissions.This study investigates the potential of using fresh GP in dairy cow feeding and its effects on CH 4 emissions.Multiparous Holstein dairy cows (n = 24, 205 ± 39 DIM) were housed in freestall barns and provided rations consisting of alfalfa hay, wheat hay, almond hulls, cottonseed, and grain mix.After a 2-wk adaptation period, cows were randomly assigned to one of the 3 treatments: a control diet (CON), a diet with 10% grape pomace (10% GP), and a diet with 15% GP (15% GP) on a DM basis.Treatments were arranged in a 3 × 3 Latin square design, where cows received 3 treatments over 3 periods, each period lasting for 4 wk.Rations were provided twice daily and gas emissions from cows were measured using an automated GreenFeed system.Milk production was recorded both in the morning and evening, and milk samples were collected weekly for fat, protein, lactose, SNF, MUN, and SCC analysis.For fatty acids analysis, milk samples were…

Although 3-nitroxypropanol (3-NOP) has been proven to reduce enteric methane (CH 4 ) by ∼30% in indoor systems of dairying when the additive is mixed throughout a TMR, very limited research has been done to date in grazing systems in which the most convenient method of additive supplementation is at milking twice daily. To investigate the effect of twice daily 3-NOP supplementation on enteric CH 4 emissions, a 12-wk study was undertaken in which treatment cows (n = 26) were supplemented with 3-NOP (80 mg/kg DMI) twice daily at morning and evening milking, and control cows (n = 26) received no additive supplementation. Enteric CH 4 , hydrogen (H 2 ) and carbon dioxide (CO 2 ) were measured using GreenFeed units, and milk production, BW, BCS, and DMI were monitored to determine the effect of 3-NOP supplementation on productivity. No significant effect was observed for 3-NOP supplementation on any of the aforementioned parameters with the exception of CH 4 and H 2 production, respectively. Cows supplemented with 3-NOP produced 1.6-fold more H 2 ( P < 0.001) across a 24-h period, with…

Probiotics are increasingly used as starter cultures to produce fermented dairy products; however, few studies have investigated the role of probiotics in milk fermentation metabolism. The current study aimed to investigate whether adding Bifidobacterium animalis ssp. lactis Probio-M8 (Probio-M8) as a starter culture strain could improve milk fermentation by comparing the physicochemical characteristics and metabolomes of fermented milks produced by a commercial starter culture with and without Probio-M8. Our results showed that adding Probio-M8 shortened the milk fermentation time and improved the fermented milk texture and stability. Metabolomics analyses revealed that adding Probio-M8 affected mostly organic acid, AA, and fatty acid metabolism in milk fermentation. Targeted quantitative analyses revealed significant increases in various metabolites related to the sensory quality, nutritive value, and health benefits of the probiotic fermented milk, including 5 organic acids (acetic acid, lactic acid, citric acid, succinic acid, and tartaric acid), 5 EAA (valine, arginine,…

Milk lactose content (LC) physiologically decreases with parity order in dairy cows, but also after udder health inflammation(s) and in presence of elevated milk SCC in subclinical cases.Therefore, the progressive decrease in milk LC observed along cows' productive life can be attributed to a combination of factors that altogether impair the epithelial integrity, resulting in weaker tight junctions, e.g., physiological aging of epithelium, mechanical epithelial stress due to milking, and experienced clinical or subclinical mastitis.Mastitis is also known to affect the udder synthesis ability, so our intention through this study was to evaluate if there is a cumulative and lasting effect of mammary gland inflammation(s) on milk yield (MY) and LC.For this purpose, we used diagnoses of clinical mastitis and milk data of Austrian Fleckvieh cows to evaluate the effect of cumulative mastitis events on LC and MY.Only mastitis diagnoses recorded by trained veterinarians were used.Finally, we investigated if cumulative mastitis is a heritable trait and whether it is genetically correlated…

Dairy farms in the United States have changed in many ways over the past 50 yr. Milk production efficiency has increased greatly, with ∼30% fewer cows producing about twice the amount of milk today. Other improvements include increases in crop yields, fuel efficiency of farm equipment, and efficiency in producing most resources used on farms (e.g. electricity, fuel, fertilizer). These improvements have led to changes in the environmental impact of farms. Through simulation of representative dairy farms in 1971 and 2020, changes in nutrient losses and farmgate life cycle assessments of greenhouse gas (GHG) emissions, fossil energy use, and blue (ground and surface) water use were determined for 6 regions and the United States. For all environmental metrics studied, intensities expressed per unit of fat- and protein-corrected milk produced were reduced, but the total effects over all farms or milk produced increased for 5 of the 13 environmental metrics. Reductions in the impacts of dairy farms in the eastern United States were offset by large increases in western regions because of a…

Milk powder, a nutrient-rich dairy product, lacks comprehensive information summarizing its specific properties when produced by spray- and freeze-dried technologies from different sources. Therefore, this study investigated the differences in physicochemical properties, microstructure, and proteome of spray- and freeze-dried milk powders from bovine, goat, and horse sources. The results revealed that spray-dried milk powder exhibited a smaller particle size, lower air content within the powder particles, inferior reconstitution properties, and lower lactose crystallinity compared with freeze-dried milk powder. Additionally, among the studied varieties, horse milk powder showed the lowest flowability but the most effective reconstitution properties. Proteomic analysis indicated that freeze-dried milk powder exhibited higher levels of immune-related proteins, including complement C3, C7, and complement factor B, and antimicrobial enzymes such as lysozyme and lactoperoxidase compared with spray-dried milk powder. Furthermore, specific milk powders contained more immune-related…

The objective of this meta-analysis was to quantify the potential of CH 4 -mitigating strategies in dairy cattle when accounting for the effects of treatment dose, dietary nutrient composition, and supplementation period.Data from 218 studies with dairy cattle published between 1963 to 2022 were reviewed.Individual CH 4 mitigation strategies selected for the analysis were algae (Asparagopsis spp.), 3-nitrooxypropanol, nitrate, lipids, plant secondary compounds, and direct-fed microbials (DFM).Response variables evaluated were daily CH 4 emission (g/d), CH 4 yield (g CH 4 /kg DMI), and CH 4 intensity (g CH 4 /kg milk yield [MY] and ECM).Relative mean difference between treatment and control means reported in the studies were calculated and used in the statistical analysis.Robust variance estimation method was used to analyze the effects of CH 4 mitigation strategies.Dose, forage-to-concentrate ratio (F:C), dietary concentrations of CP, ether extract (EE), NDF, ADF, and starch, and supplementation period were used as continuous explanatory variables.Data for algae supplementation were…

The milk fat globule membrane (MFGM) is a complex structure that surrounds the surface of fat globules in the milk of mammals. The MFGM is rich in bioactive compounds such as phospholipids, glycoproteins, and sphingolipids. Recent research highlights its important role in human health, particularly in infant nutrition, where it contributes to cognitive development, immune function, and gastrointestinal health. This review article examines the variability in commercial MFGM ingredients derived from dairy sources, detailing the impact of processes used to extrapolate the bioactive rich fractions from the MFGM. The potential applications of MFGM in food products, especially infant formulas, are emphasized, showcasing its ability to improve nutritional outcomes. Furthermore, the review discusses clinical studies that demonstrate the health benefits associated with MFGM supplementation, including enhanced cognitive performance and reduced incidence of infections in infants. Some of the underlying mechanisms behind the health-enhancing effects are elucidated in this review. Overall, this…

Heat stress (HS) poses significant challenges to the dairy industry, resulting in reduced milk production, impaired reproductive performance, and compromised animal welfare. Therefore, understanding the molecular mechanisms underlying cellular responses to HS is crucial for developing effective strategies to mitigate its adverse effects. Heat shock protein 70 (HSP70) has emerged as a potential player involved in cellular thermotolerance in dairy cows. This review provides a comprehensive overview of the role of HSP70 as a molecular chaperone in cellular thermotolerance in dairy cows under HS. HSP70 facilitates proper protein folding and prevents the aggregation of denatured proteins. By binding to misfolded proteins, it helps maintain protein homeostasis and prevents the accumulation of damaged proteins during HS. Additionally, HSP70 interacts with various regulatory proteins and signaling pathways, contributing to the cellular adaptive response to HS. The upregulation of HSP70 expression in response to HS is regulated by a complex network involving heat shock factors (HSF), heat…

This article summarizes the applications of biosensors and biomimetic sensors in the detection of residues in dairy products. Biosensors use biological molecules, such as enzymes or antibodies, to detect residual substances in dairy products, demonstrating high specificity and sensitivity. Biomimetic sensors, inspired by biosensors, use synthetic materials to mimic biological sensing mechanisms, enhancing stability and reproducibility. Both sensor types have achieved notable success in detecting pesticide residues, veterinary drugs, bacteria, and other contaminants in dairy products. The applications of biological and biomimetic sensors not only improve the efficiency of residue detection in dairy products but also have the potential to reduce the time and cost of traditional methods. Their specificity and high sensitivity make them powerful tools in the dairy industry, thus contributing to ensuring the quality and safety of dairy products and meeting the growing consumer demands for health and food safety.

Bovine mastitis is a prevalent infectious disease in dairy herds worldwide, resulting in substantial economic losses. Staphylococcus aureus is a major cause of mastitis in animals, and its antibiotic resistance poses challenges for treatment. Recently, renewed interest has focused on the development of alternative methods to antibiotic therapy, including bacteriophages (phages), for controlling bacterial infections. In this study, 2 lytic phages, vB_SauM_JDYN (JDYN) and vB_SauM_JDF86 (JDF86), were isolated from the cattle sewage effluent samples collected from dairy farms in Shanghai. The 2 phages have a broad bactericidal spectrum against Staphylococcus of various origins. Genomic and morphological analyses revealed that the 2 phages belonged to the Myoviridae family. Moreover, JDYN and JDF86 remained stable under a wide temperature and pH range and were almost unaffected in chloroform. In this study, we prepared a phage cocktail (PHC-1) which consisted of a 1:1:1 ratio of JDYN, JDF86, and SLPW (a previously characterized phage). We found that PHC-1 showed the strongest…

Live body weight (LBW) is one of the most important parameters for supervising the growth and development of livestock. The yak ( Bos grunniens ) is a special species of cattle that lives on the Qinghai-Tibetan Plateau. Yaks are more untamed than regular cattle breeds, so it is more challenging to measure their LBW. In this study, YOLOv8 yak detection and LBW estimation models were used to automatically estimate yak LBW in real time. First, the proper posture (normal posture) and individual yak identification was confirmed and then the YOLOv8 detection model was used for LBW estimation from 2-dimensional images. Yak LBW was estimated through yak body parameter extraction and a simple linear regression between the estimated yak LBW and the actual measured yak LBW. The results showed that the overall detection performance for normal yak posture was described by precision, recall, and mean average precision 50 (mAP50) indicators, reaching 81.8%, 86.0%, and 90.6%, respectively. The best yak identification results were represented by precision, recall, and mAP50 values of 97.8%, 96.4%,…

Recent advances in our understanding of methanogenesis have led to the development of antimethanogenic feed additives (AMFA) that can reduce enteric methane (CH 4 ) emissions to varying extents, via direct targeting of methanogens, alternative electron acceptors, or altering the rumen environment. Here we examine current and new approaches used for the accounting (i.e., quantification) of enteric CH 4 abatement by the use of AMFA in the livestock sector from the individual animal to the global scale. Along with this process, recommendations are provided on how to account for the mitigation potential at the animal level, as well as in farm-scale models, emissions trading schemes, life cycle assessment, and carbon (C) footprinting tools, and in regional and national inventories. In addition, an assessment of uncertainties and potential trade-offs and off-setting with the use of AMFA (i.e., efficacy vs. effectiveness, upstream and downstream emissions) is provided. The accounting of on-farm enteric CH 4 emissions and benefits from the use of AMFA starts with the ruminant animal (with…

This study aimed to screen novel immunomodulatory peptides from casein hydrolysates (CH) using alcalase and flavorzyme by virtual screening, and their molecular mechanism were further studied. Based on the primary structural characteristics of immunomodulatory peptides, along with their hydrophobicity and isoelectric point, 3 novel immunomodulatory peptides (ALPMHIR, AMKPWIQPK, NPWDQVKR) were quickly found using virtual screening. These peptides exhibited strong interactions with TLR2/TLR4 through hydrogen bonding and hydrophobic interactions. Molecular docking verified that the key binding sites, such as Ile733, Ala732, and Phe774 in TLR2/TLR4 contributed to docking. Interestingly, the peptide AMKPWIQPK exhibited the strongest immunomodulatory activity and anti-inflammatory activity as 2-way immunomodulatory peptides. Based on western blot analysis and validation using specific inhibitors against MAPK/NF-κB signaling pathways, the results demonstrated that AMKPWIQPK could recognize the TLR2 and TLR4 receptor of the macrophages to upregulate the phospho-IκBα, phospho-p38, and…

The objective of this study was to determine the potential effect and interaction of 3- nitrooxypropanol (3-NOP; Bovaer®) and whole cottonseed (WCS) on lactational performance, and enteric methane (CH 4 ) emission of dairy cows. A total of 16 multiparous cows, including 8 Holstein Friesian (HF) and 8 Brown Swiss (BS) [224 ± 36 d in milk, 26 ± 3.7 kg milk yield], were used in a split-plot design, where the main plot was the breed of cows. Within each subplot, cows were randomly assigned to a treatment sequence in a replicated 4 × 4 Latin Square design with 2 × 2 factorial arrangements of treatments with 4, 24-d periods. The experimental treatments were: 1) Control (basal TMR), 2) 3-NOP (60 mg/kg TMR DM), 3) WCS (5% TMR DM), and 4) 3-NOP + WCS. The treatment diets were balanced for ether extract, crude protein, and NDF contents (4%, 16%, and 43% of TMR DM, respectively). The basal diets were fed twice daily at 0800 and 1800 h. Dry matter intake (DMI) and milk yield were measured daily, and enteric gas emissions were measured (using the GreenFeed system) during the last 3 d of each…

Condensed tannins (CT) are plant polyphenols that can affect feed digestibility and are potentially able to reduce enteric methane emissions in ruminants. In this in vivo trial with 8 lactating goats, we investigated the effects of 4 levels of inclusion of a commercial CT extract from quebracho (0, 2, 4, 6% on DM basis; C, Q2, Q4, Q6, respectively). The experimental design was a repeated 4 × 4 Latin square with 28-d periods (24 d of diet adaptation and 4 d of sample collection) using metabolic cages and 4 open circuit respiration chambers. The inclusion of CT in the diets did not affect the dry matter intake (DMI) but caused a linear decrease in diet digestibility, with reductions up to −11% for dry matter (DM), −21% for crude protein (CP), −23% for neutral detergent fiber (aNDFom), and −13% for gross energy, when comparing the Q6 and C diets. However, ruminal total volatile fatty acids (VFA) concentration was not affected by CT, although there were changes in VFA proportions. Milk yield (g/d) was highest for Q4 (3371) and lowest for Q6 (3066). In terms of milk composition, CT…

Biofilm formation allows microorganisms including bacteria to persist on abiotic or biotic surfaces, to resist treatments with biocides (disinfectants and antibiotics), and to evade the immune response in animal hosts much more than they do in the planktonic form. Bacteria able to form biofilm can be troublesome in the dairy industry, both by causing clinical symptoms in livestock and by colonizing milking devices and milk processing equipment, resulting in dairy products of lower quality and sometimes raising serious food safety issues. In fact, most of the bacterial species isolated frequently in the dairy chain have the ability to form biofilm. Common examples include Staphylococcus aureus and other staphylococci that frequently infect mammary glands but also Bacillus spp., Listeria monocytogenes, and Pseudomonas spp., which cause spoilage of dairy products and sometimes foodborne illnesses. The economic losses due to biofilm formation in the dairy industry are considerable, and scientists are constantly solicited to develop new antibiofilm strategies, especially using biocides…

Lactoferrin is widely found in milk and has the ability to bind iron. Previous studies have reported that lactoferrin was effective in the prevention and treatment of acute alcohol-induced liver injury (AALI). Ferroptosis is a recently discovered cell death and is involved in the development of AALI. However, the potential role of lactoferrin in acute alcohol-induced ferroptosis is still unclear. In this study, we observed that lactoferrin (10, 20 and 40 μg/mL) significantly mitigated alcohol (300 mM)-induced injury in vitro. Additionally, lactoferrin (100 and 200 mg/kg bw) significantly alleviated alcohol (4.8 g/kg bw)-induced injury in vivo. Our results showed that lactoferrin inhibited alcohol-induced upregulation of the ferroptosis marker protein ACSL4 and downregulation of GPX4. Meanwhile, lactoferrin treatment successfully reversed the elevated Malondialdehyde (MDA) levels and the reduced Glutathione (GSH) levels caused by alcohol treatment. These results can indicate that lactoferrin significantly decreased ferroptosis in vivo and in vitro. Lactoferrin has the potential to…

As the stress-inducible isoform of the heat-shock protein 90 (HSP90), the HSP90AA1 gene encodes HSP90α and plays an important role in heat stress (HS) response. Therefore, this study aimed to investigate the role of the HSP90AA1 gene in cellular responses during HS and to identify functional SNPs associated with thermotolerance in Holstein cattle. For the in vitro validation experiment of acute HS, cells from the Madin-Darby bovine kidney cell line were exposed to 42°C for 1 h, and various parameters were assessed, including cell apoptosis, cell autophagy, and the cellular functions of HSP90α by using its inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG). Furthermore, the polymorphisms identified in the HSP90AA1 gene and their functions related to HS were validated in vitro. Acute HS exposure induced cell apoptosis, cell autophagy, and upregulated expression of the HSP90AA1 gene. Inhibition of HSP90α by 17-AAG treatment had a significant effect on the expression of the HSP90α protein and increased cell apoptosis. However, autophagy decreased in comparison to the control…

Identifying genome-enabled methods that provide more accurate genomic prediction is crucial when evaluating complex traits such as dairy cow behavior. In this study, we aimed to compare the predictive performance of traditional genomic prediction methods and deep learning algorithms for genomic prediction of milking refusals (MREF) and milking failures (MFAIL) in North American Holstein cows measured by automatic milking systems (milking robots). A total of 1,993,509 daily records from 4,511 genotyped Holstein cows were collected by 36 milking robot stations. After quality control, 57,600 SNPs were available for the analyses. Four genomic prediction methods were considered: Bayesian least absolute shrinkage and selection operator (LASSO), multiple layer perceptron (MLP), convolutional neural network (CNN), and GBLUP. We implemented the first 3 methods using the Keras and TensorFlow libraries in Python (v.3.9) but the GBLUP method was implemented using the BLUPF90+ family programs. The accuracy of genomic prediction (mean square error) for MREF and MFAIL was 0.34 (0.08) and 0.27…

The synergistic fermentation of milk by Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus is one of the key factors that determines the quality of yogurt. In this study, the mechanism whereby yogurt flavor compounds are produced by a mixture of S. thermophilus SIT-20.S and L. delbrueckii ssp. bulgaricus SIT-17.B were investigated by examining the flavor production, growth, and gene transcription of these strains. The results showed that yogurt produced by a 10:1 mixture of the aforementioned strains had the highest abundance of acetoin, whereas yogurt produced by a 1:1 mixture had the highest abundance of diacetyl and acetaldehyde. In addition, the growth of S. thermophilus SIT-20.S was enhanced in the 10:1 mixture. Transcriptomic analysis revealed differentially expressed genes in the flavor-compound-related pathways of S. thermophilus SIT-20.S and L. delbrueckii ssp. bulgaricus SIT-17.B in yogurts produced by 10:1 and 1:1 mixtures compared with those produced by either strain alone. Mixed fermentations regulated the expression of genes related to glycolysis,…

Hyaluronic acid (HA) has been approved to be added to milk and other dairy products, it has highly water-binding ability, which can combine with a large number of water molecules through intramolecular hydrogen bonding to form high viscous gels. In addition, HA is one of the prebiotics, can provide health benefits such as anti-aging, anti-inflammatory, angiogenic effects, is a potential additive for enhancing the quality of yogurt. Therefore, the aim of this study was to evaluate the effect of 0%, 0.02%, 0.05%, 0.1%, 0.25%, and 0.5% HA on rheological properties, functional properties, thermal stability, protein stability, protein structure, and protein fractions of yogurt. With the addition of HA, the storage modulus is larger than the loss modulus in all the samples, which is a typical characteristic of gel networks, and the microstructures of the yogurt samples showed a continuous and more homogeneous spatial network structure. Overall, the highest concentration (0.5%) had a positive effect on the yogurt characteristics, such as higher water-holding capacity and foam stability,…

The objective of this study was to evaluate the Green-Feed system (GF) and respiration chambers (RC) for daily and intraday measurements of the enteric gaseous exchange, as well as the metabolic heat production, lying behavior, and feed intake (FI) rate of dairy cows at these 2 respective housing conditions (tiestall barn [TSB] vs. RC) during the summer periods.Sixteen multiparous lactating dairy cows were recruited and arranged in a randomized complete block design with a baseline period established for each cow.Cows were given a basal diet (CON) for a baseline period of 7 d and were then fed a 3-nitrooxypropanol (3-NOP)-containing feed for the subsequent 26 d as experimental period.During both the baseline and the last 7 d of treatment period, gaseous exchanges of each animal were measured in the TSB using GF for 8 staggered measurements over 3 d, immediately followed by the measurement in RC for 2 d.Corresponding DMI, milk yield, and behavior parameters (e.g., lying behavior and FI rate) in TSB and RC were recorded.The correlation coefficients of CH 4 and H 2 using raw data were…

The aim of this study was to compare selected physical (density) and physicochemical (color, pH, titratable acidity) properties and the fatty acid profile of dairy UHT milk and its plant-based analogs (i.e., almond, soy, rice, oat, and coconut beverages). Ten products of each type were analyzed in each group. UHT milk was characterized by higher values of color lightness (L*) and titratable acidity than all plant-based milk alternatives, higher yellowness (b*) than rice drink, higher density than the almond drink, and higher pH than rice and coconut drinks. In comparison with UHT milk, all plant-based beverages were characterized by higher redness (a*), the soy drink was characterized by higher values of b* and chroma (C*), and almond and soy drinks had higher pH values. In the group of nondairy beverages, the values of b* and C* were highest in the soy drink, and the value of a* was highest in the almond drink. Almond drink had the highest pH value, and soy and coconut drinks had the highest titratable acidity. Rice drink had higher density than oat, soy, and almond drinks. The…

The nutritional components and quality of milk are influenced by the rumen microbiota and its metabolites at different lactation stages. Hence, rumen fluid and milk samples from 6 dairy cows fed the same diet were collected during peak lactation, early mid-lactation, and later mid-lactation. Untargeted metabolomics and 16S rRNA sequencing were applied for analyzing milk and rumen metabolites, as well as rumen microbial composition, respectively. The levels of lipid-related metabolites, l-glutamate, glucose-1-phosphate, and acetylphosphate in milk exhibited lactation-dependent attenuation. Maltol, N-acetyl-d-glucosamine, and choline, which are associated with milk flavor or coagulation properties, as well as l-valine, lansioside A, clitocine, and ginsenoside La, increased significantly in early mid-lactation and later mid-lactation, especially in later mid-lactation. The obvious increase in rumen microbial diversities (ACE and Shannon indices) were observed in early mid-lactation compared with peak lactation. Twenty-one differential bacterial genera of the rumen were identified, with…

Ultra-instantaneous UHT (UI-UHT, >155°C, <0.1 s) treated milk exhibits higher retention of active protein than regular UHT milk. However, UI-UHT products demonstrate increased susceptibility to destabilization during storage. This study aimed at monitoring the destabilizing process of UI-UHT milk across different storage temperatures and uncovering its potential mechanisms. Compared with regular UHT treatment, ultra-instantaneous treatment markedly accelerated the milk's destabilization process. Aged gel formation occurred after 45 d of storage at 25°C, whereas creaming and sedimentation were observed after 15 d at 37°C. To elucidate the instability mechanism, measurements of plasmin activity, protein hydrolysis levels, and proteomics of the aged gel were conducted. In UI-UHT milk, plasmin activity, and protein hydrolysis levels significantly increased during storage. Excessive protein hydrolysis at 37°C resulted in sedimentation, whereas moderate hydrolysis and an increase in protein particle size at 25°C resulted in aged gel formation. Proteomics analysis results indicated that…