ABSTRACT: Small ruminant milk may offer a viable alternative to cow milk, whereas human milk, the gold standard for infant nutrition, exhibits dynamic composition. This study analyzed the milk fat globules (MFG) particle size, fatty acid (FA) composition, and milk fat globule membrane (MFGM) proteome in human, goat, and sheep colostrum and mature milk. The smallest and largest average MFG particle sizes were identified in goat colostrum and sheep mature milk, respectively. Unsaturated FA were most prevalent in human colostrum (HC; 70.04%), whereas small ruminant milks were characterized by a higher proportion of saturated FA (57.07%–77.77%). The differential expression of FA is speculated to be associated with the variation in FA metabolic proteins on MFGM. A total of 1,658 MFGM proteins were identified. Compared with small ruminant milks, glycolysis-related proteins, such as phosphoglycerate mutase and pyruvate kinase, and antigen-presenting proteins, such as toll-like receptors and HLA molecules, were most abundant in HC, with higher levels of antioxidant-related proteins observed in human mature milk (HM). By emphasizing the differences in MFG between HC, HM, and small ruminant milk from the perspectives of particle size, FA, and proteomics, this study provides data supporting the personalized improvement of infant formula.
ABSTRACT: Given global warming and the growing dairy cow population, heat stress in dairy herds is of increasing concern. During heat stress, dairy cows suffer from compromised productivity and animal welfare in terms of reduced feed intake and milk production, decreased reproductive performance, and generally increased risk of health problems. These effects and their interactions are complex and are usually quantified separately; thus, a comprehensive understanding of the herd-level performance is missing. Moreover, compromised animal welfare and productivity may impact enteric methane (CH4) emission; however, these effects have rarely been investigated. Therefore, by performing herd simulation, this study aimed to model the impact of heat stress on dairy production and enteric CH4 emissions by aggregating its effects on milk production, reproduction, and health. Specifically, 10 scenarios (including baseline) were simulated in a conventional, high-yielding Danish herd by incorporating different combinations of effects on milk production, reproduction, and health of heat stress in different exposure durations (1, 2, and 4 mo). Sensitivity analyses were further conducted to account for the effects of different reduction rates in feed efficiency (kg ECM/kg DMI). Results showed that heat stress decreased the herd-level milk yield by up to 8.6% if all effects were combined in a duration of 4 mo, whereas a direct effect on milk yield only decreased herd-level yield by up to 6.9%. Heat stress increased the herd-level enteric CH4 intensity ranging from 0.8% to 6.6% across all 9 scenarios as compared with the baseline scenario. When a reduction in feed efficiency by 19.2% was assumed, the herd-level CH4 intensity increased by up to 4.4% during 2 mo. Overall, our results showed large impacts of heat stress on both dairy production and CH4 emissions and suggest the need to implement management mitigation strategies in heat-stressed dairy herds.
Anina Vogt, Susanne Waiblinger, Rupert Palme
et al.
ABSTRACT: Weaning and separation remain among some of the biggest challenges for cow-calf contact systems, making the development of practical and low-stress separation methods mandatory for future success of these systems. This study aimed to compare behavioral and physiological responses of dairy cows to separation from their calves after 3 mo of full-time contact, with either the 2-step method (NF, 2 wks full-time contact while calves wore a nose flap, 1 wk fence-line contact before total separation, n = 18) or by gradual reduction of contact time between cow and calf (GR, 1 wk half day contact, 1 wk morning contact, 1 wk fence-line contact before total separation, n = 18). Vocalizations and searching behavior were observed on 4 d/wk from 1 wk before separation until 1 wk after total separation. During the same period, lying behavior and rumination time was automatically assessed via accelerometers and pressure sensors. Fecal and blood samples were collected twice per week from day −1 until +23 relative to separation start for analysis of fecal cortisol metabolites and the immune response. Milk yield in the parlor was continuously recorded. Statistical analysis was conducted using linear mixed effects models. We found no difference between the 2 separation methods in any of the examined behavioral and physiological response variables. However, a significant increase in vocalizations and searching behavior compared with baseline was present with both methods. Furthermore, there was a transient increase in physiological distress markers and a short-lived retention of milk yield at initiation of treatments, indicating that both methods induced distress for the cows. Descriptively, there were large interindividual differences between cows as well as a different temporal distribution in occurrence of behavioral responses, as GR cows vocalized most frequently during the week with fence-line contact and after total separation from the calf, while NF cows reacted strongest during the 2 wk while calves wore the nose flap. Milk yield was higher in NF than GR cows during the 2 wk while GR calves had time-restricted access to their dams and NF calves were prevented from suckling, but showed no difference afterward. However, similar evening milk yields of GR cows in the weeks with half-day and morning contact, indicated that the weekly reductions in contact time worked in a rather stepwise than gradual manner, which warrants further improvement of the GR method. Taken together, results showed that cows experienced distress during separation with the GR method, when implemented over 3 wk in 3 steps, as well as with the NF method, but differences between individuals were considerable.
ABSTRACT: Protein-encapsulated fat (PEF) blends are routinely used for manufacturing calf milk replacers (MR). The use of PEF blends improves fat mixability to ensure MR when mixed and fed as a homogeneous solution for neonatal calves. A new alternative PEF based on choice white grease (CWG) has been developed to improve its mixability and solubility to ensure a homogeneous MR solution. The alternative PEF is hypothesized to support similar growth performance (ADG, DMI, and feed efficiency) of neonatal calves and potentially reduce costs. The study objective was to evaluate CWG PEF as an alternative to a standard animal lard–tallow (ALT) PEF blend to mix a MR to be fed to Holstein calves. A total of 40 Holstein bull calves (2–5 d old) were blocked by BW and randomly assigned to 1 of 2 treatments (n = 20/treatment) using a randomized complete block design. The treatments were (1) CWG used to manufacture a PEF blend, and (2) ALT used to manufacture a PEF blend. The PEF blends were then used to manufacture 2 experimental MR. Both MR were formulated to contain a ratio of 22% CP to 20% fat with Met, Lys, Thr, Trp, and Val AA specifications, and fed twice per day along with ad libitum 22% CP mini-pelleted calf starter (CS) and water. The MR were fed at 15% solids at 0630 and 1800 h, fed at 0.567 kg/d for d 1 to 14, increased to 0.85 kg/d for d 15 to 35, and reduced to once per day at 0.425 kg/d for d 36 to 42 to facilitate weaning at 42 d with ad libitum CS fed for the remainder of the 56-d study. Calves fed CWG and ALT PEF blends were similar (P > 0.10) in BW gain (37.4 and 35.9 kg for CWG and ALT, respectively), ADG (679.8 and 652.7 g/d), CS DMI intake (0.69 and 0.67 kg/d), total DMI (1.19 and 1.17 kg/d) and feed conversion (0.559 and 0.543 kg/kg). No significant differences were detected in frame gains and fecal scores among treatments. Choice white grease can be used to manufacture a PEF blend for use in manufacturing MR for feeding neonatal calves by maintaining growth performance and health at potentially lower cost.
Muhammad Aqeel, Ahmed Sohaib, Muhammad Iqbal
et al.
ABSTRACT: 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 imaging-based adulterant detection and categorization. Preprocessing involves radiometric correction, image resizing, region of interest selection for feature extraction, and empirical line method to calculate spectral reflectance signature. Machine learning techniques (logistic regression, decision tree, support vector machine, and linear discriminant analysis [LDA]), are employed, with LDA excelling in adulteration identification by learning the spectral signatures. These algorithms are trained and validated using a developed milk adulteration dataset. Training, testing, and validation accuracy, precision, recall, F1 score, kappa, and Matthew's correlation coefficient metrics showcase the effectiveness of the proposed pipeline, outclassing numerous state-of-the-art approaches with a validation accuracy of 100%. In conclusion, this study established a multiclass model capable of detecting milk adulterant behavior, showing significant practical application for milk quality assessment.
ABSTRACT: In the current study, whey protein fractal assembly (FA) particles were manufactured and used as emulsifying agent to manufacture oil-in-water (o/w) emulsion system, namely FA emulsion. The cold-set gelation behavior of FA emulsion was investigated in terms of gel-phase stability, rheology, and tribology. Fractal assembly particles were prepared by heating whey protein isolate (WPI) solution (90 g·L−1) at 80°C for 24 h. The fractal morphology of FA particles was observed using transmission electron microscopy. The “protein aggregation index” for WPI solution and FA sol was found as (mean ±SD) 4.3% ± 0.6% and 78.2% ± 0.7%, respectively. The FA sol had z-average diameter of 133.16 nm ± 3.59 nm. The WPI and FA dispersion systems had similar isoelectric points (IEP) at ∼pH 4.6. FA particles had higher surface hydrophobicity as compared with WPI. The WPI and FA stabilized emulsions showed similar droplet size distribution, however, the FA emulsion had higher surface charge than the WPI emulsion. The WPI and FA emulsions were then used to fabricate 18 cold-set gels by manipulating pH (4.6, 5.8, and 7.0) and added levels of Ca2+ (0, 5, and 10 mM), in which 9 gels derived from WPI emulsion were used as control samples. The WPI emulsion was not able to form self-supported and phase-stable gel under each gelation condition tested in this work, whereas FA emulsion gels demonstrated a superior syneresis stability. According to the large-amplitude oscillatory shear rheology characterization, FA emulsion gels showed both strain stiffening-softening transition and shear-thinning-thickening transition behaviors depending on the applied strain and oscillatory frequency. Lissajous-Bowditch plots revealed unsteady rheological behavior, ranging from perfect plastic to Bingham plastic depending upon the applied angular frequency. The selected FA emulsion gels demonstrated acceptable lubrication behaviors. These findings indicate that the characterized FA emulsion gels may be used as protein-based texturizers in diversified food matrixes.
ABSTRACT: Milk fever is one of the most historically relevant diseases of dairy cows. It is caused by tremendous calcium (Ca) expenditure at the initiation of lactation, so severe that cows can no longer stand and, if left untreated, die. Fortunately, through prepartum nutritional improvements, this version of clinical hypocalcemia is rare in the United States. Nonetheless, the opinion that all versions of postpartum hypocalcemia are detrimental remains pervasive, which is particularly significant given that 50% of cows are subclinically hypocalcemic after calving. This has led to a variety of available management and treatment strategies, ranging from prepartum dietary programs to postpartum Ca gels and boluses, targeted at preventing hypocalcemia in dairy cows. Recent research has determined that postpartum dairy cows can experience different types of subclinical hypocalcemia: transient, persistent, or delayed. We now know cows experiencing transient hypocalcemia as part of the homeorhetic adaptation to lactation are the highest milk producers in modern dairy herds, whereas cows with hypocalcemia several days after calving experience disease and losses in milk production. Therefore, it is wrong to assume all postpartum hypocalcemia is detrimental and that treatment of all cases is considered necessary and beneficial. Research indicates that milk synthesis at the onset of lactation contributes to immediate postpartum hypocalcemia, and that the mammary gland is a critical factor in management of Ca homeostasis. However, cows differ in their ability to manage this phenomenon, and it is possible that immediate postpartum influences such as dry matter intake, inflammation, and immune activation affect appropriate Ca regulation in the days following calving.
Margit Bak Jensen, Laura E. Webb, Mette Vaarst
et al.
ABSTRACT: Under natural conditions, most parturient cows seek visual cover or seclude themselves from the herd when calving becomes imminent. Studies on calving site selection of dairy cows housed indoors show that predominantly older and dominant cows calve in secluded areas. This study aimed to investigate whether cows distance themselves further from herd members under spacious outdoor conditions and whether artificial hides on a pasture motivate cows to seek visual isolation from the herd. One hundred eighty-two Danish Holstein cows were allocated to 1 of 13 groups of 14 cows according to expected calving date. In 2 paddocks (each 75 × 150 m), 5 zones (75 m × 30 m) were defined; zone 0 contained the feeding and shade area, and zone 4 bordered an area with trees. Weekly and according to calving date, a group of 14 cows was moved either to a paddock that had 12 hides distributed evenly throughout zones 1 to 4 (7 groups) or to a paddock without hides (6 groups). The hides were wooden structures (3.3 m long × 1.0 m wide × 1.2 m high) that the cows could hide behind. One hundred seven cows calved within 14 d of having been moved to the paddock, and 82 of these (38 primiparous and 44 multiparous), and their calves, were included in the study. From 3 h before until 3 h after calving, the location, posture, and behavior of cows were recorded continuously from video recordings. In addition, location, posture, and behavior of the calves were recorded for the first 3 h after birth. Continuous variables were analyzed by linear mixed effects models, whereas binary data were analyzed using mixed effects logistic regression. The presence of hides did not affect selection of calving location in the paddock, but more primiparous than multiparous cows calved in zone 4; that is, furthest away from the feeding area. Before calving, primiparous cows were more likely to be positioned in zone 4 and less likely to approach and contact herd members. After calving, primiparous cows and their calves tended to be more likely to be positioned in zone 4. The more cows present in the paddock, the less likely the cows were to isolate (i.e., be further than 30 m away from any other cow) at the time of calving. In addition, the more cows in the paddock when a calf was born, the less time these calves spent in a lying posture. The results show that primiparous cows move further away from herd members at calving than multiparous cows and suggest that primiparous cows prefer to isolate themselves through distance rather than seeking artificial cover. Contrary to expectation, the hides did not make more cows select a calving site away from the feeding area.
ABSTRACT: β-Lactoglobulin (β-LG) is a major milk protein, making up more than 53% of the total whey proteins, and is seen as a valuable ingredient in food processing because of its high essential amino acid content and diverse functional applications. The Maillard reaction can occur during the storage and processing of food and generate various beneficial effects, including anti-allergenicity, antioxidant, and immunomodulatory effects. The addition of an β-LG-lactose conjugate (LGL) produced by the Maillard reaction was shown to have a strong immune-enhancing effect, increasing both nitric oxide generation and cytokine expression through activation of RAW 264.7 cells, even after in vitro digestion. Furthermore, daily LGL administration resulted in the upregulation of several immune markers in a cyclophosphamide-induced immunosuppressive mouse model, indicating that this treatment stimulates multiple immune cells, including macrophages, natural killer cells, and lymphocytes, enhancing the proliferation and activation of both the innate and adaptive immune responses. Taken together, these findings indicate that consuming LGL on a regular basis can improve immunity by increasing the natural production of various immune cells.
Gonçalo Pereira, Patrícia Simões, Ricardo Bexiga
et al.
ABSTRACT: High-yielding dairy cows experience a negative energy balance and inflammatory status during the transition period. Fat supplementation increases diet energy density, and plasma n-3 polyunsaturated fatty acids (PUFA) have been proposed to improve immune function. This study tested the hypothesis that dietary supplementation with a rumen-protected and n-3 PUFA-enriched fat could ameliorate both the energetic deficit and immune status of postpartum high-yielding dairy cows, improving overall health and reproductive efficiency. At 11 d in milk (DIM), cows were randomly allocated to groups (1) n-3 PUFA (n = 29), supplemented with encapsulated linseed oil supplying additional up to 64 g/d (mean 25 ± 4 g/d) of α-linolenic acid (ALA), or (2) control (n = 31), supplemented with hydrogenated palm oil without ALA content. Fat supplements of the n-3 PUFA and control groups were available through an automated, off-parlor feeding system, and intake depended on the cow's feeding behavior. Plasma ALA concentrations were higher in n-3 PUFA than control cows, following a linear relation with supplement ingestion, resulting in a lower n-6/n-3 ratio in plasma. Metabolic parameters (body condition score and glucose and β-hydroxybutyric acid blood concentrations) were unaffected, but milk yield improved with increased intake of fat supplements. Plasma total adiponectin concentrations were negatively correlated with ingestion of n-3 PUFA-enriched fat supplement, following a linear relation with intake. Conception rate to first AI increased with higher intake of both fats, but a decrease of calving-to-conception interval occurred only in n-3 PUFA cows. Postpartum ovarian activity and endometrial inflammatory status at 45 DIM were unaffected. In conclusion, this study evinced a positive linear relation between rumen-protected linseed fat intake and plasma n-3 PUFA concentrations, which modulated adiponectin expression and improved reproductive parameters.
Marie Balasse, Rosalind Gillis, Ivana Živaljević
et al.
Abstract Present-day domestic cattle are reproductively active throughout the year, which is a major asset for dairy production. Large wild ungulates, in contrast, are seasonal breeders, as were the last historic representatives of the aurochs, the wild ancestors of cattle. Aseasonal reproduction in cattle is a consequence of domestication and herding, but exactly when this capacity developed in domestic cattle is still unknown and the extent to which early farming communities controlled the seasonality of reproduction is debated. Seasonal or aseasonal calving would have shaped the socio-economic practices of ancient farming societies differently, structuring the agropastoral calendar and determining milk availability where dairying is attested. In this study, we reconstruct the calving pattern through the analysis of stable oxygen isotope ratios of cattle tooth enamel from 18 sites across Europe, dating from the 6th mill. cal BC (Early Neolithic) in the Balkans to the 4th mill. cal BC (Middle Neolithic) in Western Europe. Seasonal calving prevailed in Europe between the 6th and 4th millennia cal BC. These results suggest that cattle agropastoral systems in Neolithic Europe were strongly constrained by environmental factors, in particular forage resources. The ensuing fluctuations in milk availability would account for cheese-making, transforming a seasonal milk supply into a storable product.
Automatic milking systems (AMS), or milking robots, are becoming widely accepted as a milking technology that reduces labour and increases milk yield. However, reported amount of labour saved, changes in milk yield, and milk quality when transitioning to AMS vary widely. The purpose of this study was to document the impact of adopting AMS on farms with regards to reported changes in milking labour management, milk production, milk quality, and participation in dairy herd improvement (DHI) programmes. A survey was conducted across Canada over the phone, online, and in-person. In total, 530 AMS farms were contacted between May 2014 and the end of June 2015. A total of 217 AMS producers participated in the General Survey (Part 1), resulting in a 41% response rate, and 69 of the respondents completed the more detailed follow-up questions (Part 2). On average, after adopting AMS, the number of employees (full- and part-time non-family labour combined) decreased from 2.5 to 2.0, whereas time devoted to milking-related activities decreased by 62% (from 5.2 to 2.0 h/day). Median milking frequency was 3.0 milkings/day and robots were occupied on average 77% of the day. Producers went to fetch cows a median of 2 times/day, with a median of 3 fetch cows or 4% of the herd per robot/day. Farms had a median of 2.5 failed or incomplete milkings/robot per day. Producers reported an increase in milk yield, but little effect on milk quality. Mean milk yield on AMS farms was 32.6 kg/cow day. Median bulk tank somatic cell count was 180 000 cells/ml. Median milk fat on AMS farms was 4.0% and median milk protein was 3.3%. At the time of the survey, 67% of producers were current participants of a DHI programme. Half of the producers who were not DHI participants had stopped participation after adopting AMS. Overall, this study characterized impacts of adopting AMS and may be a useful guide for making this transition.
Production of goat milk and its consumption in the world is increasing, and so is the population of goats which increases more than the population of other dairy animals. This is particularly true in countries where goat milk is reflection of the traditional production. Goat’s milk, in addition to the high nutritional value (better digestibility, hypoallergenic, higher buffering capacity, higher pH value) is characterized by therapeutic characteristics important for human health. The preference of goat’s milk over cow’s milk is also a higher selenium content, which is essential for the activity of the enzyme glutathione peroxidase, also significant in the prevention of cancer and cardiovascular diseases. Goat’s milk in comparison with cow’s, contains more fatty acids, which have beneficial effects on human health, especially the cardiovascular system. Goat’s milk proteins are more digestible than cow’s milk proteins, also an absorption of amino acids are more efficient. The sensitivity of people to α-lactalbumin and β-lactoglobulin of cow’s milk is negligible after replacing cow’s milk with goat’s milk. The objective of this paper is to specify benefits of goat’s milk in regard to cow’s and highlight its therapeutic and nutritional values.
Šimun Zamberlin, Neven Antunac, Jasmina Havranek
et al.
Mineral elements occur in milk and dairy products as inorganic ions and salts, as well as part of organic molecules, such as proteins, fats, carbohydrates and nucleic acids. The chemical form of mineral elements is important because it determines their absorption in the intestine and their biological utilization. The mineral composition of milk is not constant because it depends on lactation phase, nutritional status of the animal, and environmental and genetic factors. The objective of this research is to point out the research results of chemical form, content and nutritional importance of individual mineral elements that are present in various milks and dairy products.