Age-specific composition of milk microbiota in Tibetan sheep and goats.

This study investigates the dynamic changes in milk nutritional composition and microbial communities in Tibetan sheep and goats during the first 56 days of lactation. Milk samples were systematically collected at five time points (D0, D7, D14, D28, D56) post-delivery. In Tibetan sheep, milk fat, protein, and casein contents were highest on D0, gradually decreased, and stabilized after D14, while lactose and galactose levels showed the opposite trend. Goat milk exhibited similar initial peaks, with significant changes particularly between D0, D7, D14, and D56. 16S rRNA gene sequencing revealed increasing microbial diversity in both species over the lactation period. Principal coordinates analysis identified distinct microbial clusters corresponding to early (D0-D7), transitional (D14-D28), and mature (D56) stages. Core phyla, including Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, dominated the milk microbiota, with significant temporal shifts. Core microbes like Lactobacillus, Leuconostoc, and Streptococcus were common in both species, with species-specific taxa observed (e.g., Pediococcus in sheep, Shewanella in goats). Furthermore, we observed a highly shared core microbiota in sheep and goat milk, including Lactobacillus, Leuconostoc, and Streptococcus. Spearman correlation analysis highlighted significant relationships between specific microbial genera and milk nutrients. For instance, Lactobacillus positively correlated with total solids, non-fat milk solids, protein, and casein, while Mannheimia negatively correlated with protein content. This study underscores the complex interplay between milk composition and microbial dynamics in Tibetan sheep and goats, informing strategies for livestock management and nutritional enhancement. KEY POINTS: • The milk can be classified into three types based on the microbiota composition • The changes of milk microbiota are closely related to the variations in nutrition • Filter out microbiota with species specificity and age specificity in the milk.

Mammary fat globules as a source of mRNA to model alterations in the expression of some milk component genes during lactation in bovines.

BACKGROUND: The milk's nutritional value is determined by its constituents, including fat, protein, carbohydrates, and minerals. The mammary gland's ability to produce milk is controlled by a complex network of genes. Thereby, the fat, protein, and lactose synthesis must be boost in milk to increase milk production efficiency. This can be accomplished by fusing genetic advancements with proper management practices. Therefore, this study aimed to investigate the association between the Lipoprotein lipase (LPL), kappa casein CSN3, and Glucose transporter 1 (GLUT1) genes expression levels and such milk components as fat, protein, and lactose in different dairy breeds during different stages of lactation. METHODS: To achieve such a purpose, 94 milk samples were collected (72 samples from 36 multiparous black-white and red-white Holstein-Friesian (HF) cows and 22 milk samples from 11 Egyptian buffaloes) during the early and peak lactation stages. The milk samples were utilized for milk analysis and genes expressions analyses using non- invasive approach in obtaining milk fat globules (MFGs) as a source of Ribonucleic acid (RNA). RESULTS: LPL and CSN3 genes expressions levels were found to be significantly higher in Egyptian buffalo than Holstein-Friesian (HF) cows as well as fat and protein percentages. On the other hand, GLUT1 gene expression level was shown to be significantly higher during peak lactation than early lactation. Moreover, lactose % showed a significant difference in peak lactation phase compared to early lactation phase. Also, fat and protein percentages were significantly higher in early lactation period than peak lactation period but lactose% showed the opposite pattern of Egyptian buffalo. CONCLUSION: Total RNA can be successfully obtained from MFGs. The results suggest that these genes play a role in glucose absorption and lactose synthesis in bovine mammary epithelial cells during lactation. Also, these results provide light on the differential expression of these genes among distinct Holstein-Friesian cow breeds and Egyptian buffalo subspecies throughout various lactation phases.

Selection of a suitable animal model to evaluate secretion of drugs in the human milk: a systematic approach.

Lack of data on drug secretion in human milk is a concern for safe use of drugs during postpartum.Clinical studies are often difficult to perform; despite substantial improvements in computational methodologies such as physiologically based pharmacokinetic modelling, there is limited clinical data to validate such models for many drugs.Various factors that are likely to impact milk to plasma ratio were identified. A literature search was performed to gather available data on milk composition, total volume of milk produced per day, milk pH, haematocrit, and renal blood flow and glomerular filtration rate in various animal models.BLAST nucleotide and protein tools were used to evaluate the similarities between humans and animals in the expression and predominance of selected drug transporters, metabolic enzymes, and blood proteins.A multistep analysis of all the potential variables affecting drug secretion was considered to identify most appropriate animal model. The practicality of using the animal in a lab setting was also considered.Donkeys and goats were identified as the most suitable animals for studying drug secretion in milk and future studies should be performed in goats and donkeys to validate the preliminary observations.

Infant Temperament Is Associated With Milk Cortisol but Not With Maternal Childhood Trauma.

Previous studies have suggested that maternal childhood trauma (MCT) may influence infant temperament, but the underlying physiological mechanisms remain unclear. This study sought to confirm the involvement of breast milk cortisol in the link between MCT and infant temperament. The study sample included 90 mother-infant dyads recruited from the urban Polish population. MCT was assessed based on the Early Life Stress Questionnaire (ELSQ) and infant temperamental factors (surgency/extraversion, negative affectivity, and orienting/regulation) using the Infant Behavior Questionnaire-Revised at 12 months of life. Cortisol was assayed in milk samples collected at 5 months of life using the ELISA method. Based on the ELSQ median, the sample was divided into low and high MCT groups. The ANCOVA models with milk cortisol as a covariant were run to check the effect of low versus high MCT on infant temperament. We found a positive association between milk cortisol and orienting/regulation. Surprisingly, the low and high MCT groups did not significantly differ in milk cortisol. Furthermore, we found that MCT was unrelated to any infant temperamental factor. While recent literature on the association between milk cortisol and infant temperament is inconsistent, our results suggest that high orienting/regulation might be an adaptation to adverse environments such as stress. Moreover, the infant's temperament appears to be more responsive to the current exposition to maternal stress than her experience of traumatic stress.

Milk component ratios and their associations with energy balance indicators and serum calcium concentration in early-lactation spring-calving pasture-based dairy cows.

Indirect assessment of metabolic status using milk samples provides a non-invasive and objective tool for cow-level health monitoring. Milk fat-to-protein ratio (FPR) has been commonly evaluated as an indirect measure for negative energy balance (EB) in confined dairy cows. However, milk component ratios have not been explored for their association with pasture-based cows' metabolic status. The objectives of this observational study were to 1) describe milk component ratios from 0 to 45 d postpartum, 2) evaluate the associations between milk component ratios [FPR, fat-to-lactose (FLR), protein-to-lactose (PLR)] and indicators of EB (serum ß-hydroxybutyrate (BHB) concentration at 5-45 d postpartum and body condition score (BCS) change during the transition period), and 3) evaluate the associations between milk component ratios and serum Ca concentration 0-4 d postpartum in spring-calving dairy cows from pasture-based commercial farms. Milk component ratios were determined on samples collected before AM or PM milkings from 548 cows at 0-45 d postpartum (n = 970). Serum BHB and Ca determinations were performed in blood samples collected at the time of milk sample collection at 5-45 d postpartum (n = 918) and 0-4 d postpartum (n = 50), respectively; and BCS change was calculated using BCS assigned between 29 d prepartum and 45 d postpartum (n = 851). Cows' calving date, parity (1st, 2nd-3rd or ≥ 4th) and breed (Holstein-Friesian or dairy crossbred) information was obtained from the farm records. Data was analyzed by multiple linear regression. Average milk FPR, FLR and PLR were 0.70, 0.53 and 0.72, respectively. Milk FPR linearly increased while milk FLR linearly decreased postpartum both at a rate of 0.004 units per day; milk PLR decreased 0.05 units per day for the first 30 d postpartum and moderately increased afterward. Milk FPR and FLR were 0.71 and 0.52 units lower before AM than PM milking, respectively; while milk PLR was similar before AM and PM milking. Milk FPR and FLR were 0.07 to 0.10 units higher for 2nd-3rd compared with 1st and ≥ 4th parity cows. Milk PLR was 0.03 units greater for ≥ 4th compared with 2nd-3rd and 1st parity cows. Further, crossbred cows had 0.07, 0.08 and 0.03 higher milk FPR, FLR and PLR than Holstein-Friesian cows, respectively. Moderate to high P-values along with moderate to small estimated slopes and wide 95% confidence intervals were observed for the associations between milk component ratios and indicators of EB. A positive linear association was observed between milk FPR and serum Ca concentration within 4 d postpartum; milk FPR increased 0.31 units per each mmol/L increase in serum Ca concentration. Cows with low serum Ca concentration within 4 d postpartum had 0.27 units lower milk FPR compared with cows at or above the threshold (2.12 mmol/L), and tended to have 0.15 units lower milk FPR compared with cows at or above the threshold (2.00 mmol/L). In conclusion, further research is needed to reach conclusions on the association between milk component ratios determined before milking and EB indicators. The potential of milk FPR for monitoring blood Ca status warrants further investigation in early-lactation pasture-based dairy cows.

Regulation of gene expression in milk secretory pathways during secretory activation in Holstein cows.

Increased transcription of genes involved in lactose synthesis is a key feature of secretory activation of the mammary gland. We determined which genes are transcriptionally regulated during the transition from colostrum to milk in cows and whether more frequent milking of one udder half would increase milk yields and alter gene expression. We enrolled 12 Holstein cows immediately after calving, harvested colostrum, then randomly assigned one udder half to 12 h (2X) or 6 h (4X) milking intervals for 48 h after first milking. After 48 h, all quarters were milked twice daily until d7, when final quarter milk yields were collected. Yields and composition of colostrum and milk were recorded for each 12 h interval. After each milking, a strip sample of hind milk was collected for isolation of RNA from milk fat and quantification of selected transcripts via qPCR. Milk, milk fat, total protein, and lactose yields increased significantly over the initial 48 h and at d7 after calving. Quarters on 4X treatment produced more milk than the contralateral 2X quarters. Genes upregulated concomitantly with milk yields encoded α-lactalbumin (LALBA), ß-1,4-galactosyltransferase (B4GALT1), fatty acid synthase (FASN), ß casein (CSN2), and folate receptor α (FOLR1). Downregulated genes encoded monosaccharide transporters (SLC2A3, SLC2A8, SLC35A2) and enzymes involved in galactose synthesis (HK1, PGM1, GALE). Three genes were initially downregulated but later upregulated at d7 (LPIN1, SLC2A1, UGP2). Notably, milking frequency had no effect on gene expression. Sequential upregulation first of genes encoding the former enzymes, then of UGP2, may be necessary for copious milk production. However, the local effects of milking frequency on milk production during lactogenesis do not appear to be controlled by transcription of these genes related to lactose synthesis.

Application of a short-wave pocket-sized near-infrared spectrophotometer to predict milk quality traits.

Portable handheld devices based on near-infrared (NIR) technology have improved and are gaining popularity, even if their implementation in milk has been barely evaluated. Thus, the aim of the present study was to assess the feasibility of using short-wave pocket-sized NIR devices to predict milk quality. A total of 331 individual milk samples from different cow breeds and herds were collected in 2 consecutive days for chemical determination and spectral collection by using 2 pocket-sized NIR spectrophotometers working in the range of 740 to 1,070 nm. The reference data were matched with the corresponding spectrum and modified partial least squares regression models were developed. A 5-fold cross-validation was applied to evaluate individual device performance and an external validation with 25% of the dataset as the validation set was applied for the final models. Results revealed that both devices' absorbance was highly correlated but greater for instrument A than B. Thus, the final models were built by averaging the spectra from both devices for each sample. The fat content prediction model was adequate for quality control with a coefficient of determination (R2ExV) and a residual predictive deviation (RPDExV) in external validation of 0.93 and 3.73, respectively. Protein and casein content as well as fat-to-protein ratio prediction models might be used for a rough screening (R2ExV >0.70; RPDExV >1.73). However, poor prediction models were obtained for all the other traits with an R2ExV between 0.43 (urea) and 0.03 (SCC), and a RPDExV between 1.18 (urea) and 0.22 (SCC). In conclusion, short-wave portable handheld NIR devices accurately predicted milk fat content, and protein, casein, and fat-to-protein ratio might be applied for rough screening. It seems that there is not enough information in this NIR region to develop adequate prediction models for lactose, SCC, urea, and freezing point.

Replacing the forage portion of the ration with triticale hay improves the performance of Holstein dairy cows.

The aim of the present study was to assess the effect of replacing the forage portion (alfalfa, corn silage, and barley straw) in the diet of lactating Holstein cows with triticale hay (TH, × Triticosecale L.) on DMI, digestibility, ruminal fermentation variables, estimated microbial-N synthesis (EMNS), and milk production and composition. Eight Holstein cows were used in a replicated Latin square design (two 4 × 4 squares) with four 28-d periods and 4 treatments, including a TH-free diet (control), and diets replacing 33%, 66%, and 100% of the forage portion with TH. Cows were fed ad libitum with 10% carryover during the experimental periods. Intakes and in vivo digestibilities of dry matter, organic matter, crude protein, and ash-free neutral detergent fiber, rumen pH, ammonia-N, total and individual short-chain fatty acids, protozoa, and bacteria populations were evaluated using specific methods. Moreover, in vitro total gas and methane release and in vivo urinary purine derivatives, EMNS, milk production, and composition were measured. The results showed that TH diets lowered DMI, compared with the control. Apparent digestibilities of DM, OM, CP, and NDF increased with dietary TH inclusion. The addition of TH instead of the diet forage portion increased in vivo rumen pH; acetic, propionic, valeric, and isovaleric acids concentrations; cellulolytic bacteria number; and in vitro gas production. In vivo rumen ammonia-N, short-chain fatty acids, butyric acid, in vivo and in vitro total protozoa and Entodiniinae numbers, and in vitro methane production decreased with increasing dietary levels of TH instead of the forage portion. The dietary addition of TH did not affect milk yield, protein, and lactose, but increased fat-corrected milk, milk fat, fat-corrected milk:DMI ratio, and milk yield:DMI ratio. Milk urea N decreased, but urinary purine derivatives excretion and EMNS increased with increasing levels of TH in the diet. For variables with significant changes, except for isovaleric acid, there was a linear response of animals to increasing levels of TH in the diet. Results suggest that TH, which is grown with less water compared with alfalfa, corn forage, and straw, is a potential alternative to those forages by increasing milk production efficiency, milk fat, and decreasing methane emission.

Impact of cultural, nutrition, and lifestyle transition on human milk composition between the Orang Asli communities in Peninsular Malaysia: A study protocol.

Background: Human milk provided by healthy, well-nourished mothers represents the best food available for infants. Human milk is species-specific and recommended as the sole source of nutrition for the first 6 months of life and is an important food source until the infants reach 2 years of life. Unlike infant formula, which has a standardized composition, human milk composition varies among and within women. Aim: While many studies of human milk composition have been conducted, none have been done among the Orang Asli people in Malaysia. Hence, this study protocol is designed to determine the human milk composition of the Orang Asli in Peninsular Malaysia and how the transition of culture, nutrition, and different lifestyle experiences will affect the nutrient content of their milk. Methods: Quantitative (interviewer-administered questionnaire) and qualitative (focus group discussion) approaches will be employed in this study and in addition, laboratory works will also be carried out to analyze the nutrient composition of the milk samples collected from various Orang Asli subethnic groups in Peninsular Malaysia. Conclusion: Standardized, multipopulation studies of human milk composition are sorely needed to create a rigorous, comprehensive reference inclusive of nutrients and other factors. The establishment of any dietary parameters positively affecting the nutrient content of human milk may help design healthcare strategies in Malaysia to improve the quality of human milk and therefore the infants' health status.

l-Arginine supplementation for pregnant and lactating sows may improve the performance of piglets: A systematic review.

The objective was to conduct a systematic review to clarify the effects of l-arginine supplementation in pregnant and lactating sows on plasma hormone levels, milk production and composition, the body condition of sows and piglet performance. In April 2023, an online search and a systematic search were performed in the following databases: Embase, Scopus, SciELO, Web of Science, PubMed and Science Direct. The combinations of keywords used were sow and arginine and lactation; sow and arginine and lactating; sow and arginine and gestation; sow and arginine and gestating; sow and arginine and pregnancy; sow and arginine and reproduction; piglet and arginine; and sow and arginine and mammary gland. In total, 21 scientific articles with original data were selected according to preestablished criteria. Among the 21 articles, seven (33%) reported measurements of some plasma hormones, and among these, six reported an increase in the levels of at least one hormone, namely, estradiol, insulin-like growth factor 1 (IGF-1), insulin, follicle stimulating hormone, growth hormone or prolactin, with l-arginine supplementation. The parameters of milk were evaluated in 11 studies (52%), one reported an increase in protein content, and one reported an increase in IGF-1 content in milk with supplementation of this amino acid. Of the 14 studies that evaluated the performance parameters of piglets, only four reported improvements in some parameters of piglets from sows that received supplementation. Dietary supplementation of arginine for sows in the final third of gestation and/or lactation may alter the plasma levels of some hormones, which may reflect in greater development of the mammary gland tissue and, consequently, promote benefits on the performance of piglets. However, more studies are needed to evaluate the real impact of this amino acid supplementation on the physiology of the sows, in general, and the performance of suckling piglets.

Lactation traits and reproductive performances of Sahraoui female camel in two breeding systems at Algerian Sahara.

The main objective of this study is to determine the impact of the camel livestock system on individual and herd performances of milk production, lactation curve, fats, and protein concentrations. For this purpose, 13 she-camels of Sahraoui breed from the south eastern Algeria and belonging and semi-intensive system (N = 6) and intensive system (N = 7) were studied. Recording and sampling of milk were carried out at regular intervals during a full lactation. The lactation curve was estimated using Wood's gamma function and the t-test of independent groups was carried out to compare lactation performances, lactation curve, and reproductive parameters. The overall average daily milk (DMY), fat (DFY), and protein (DPY) yield were 6.77 ± 0.82 kg/day, 4.15 ± 0.91%, and 4.49 ± 0.20%, respectively. The mean of total milk yield (TMY) was 2696.39 ± 343.86 kg during a mean lactation length (LL) of 398.38 ± 20.65 days. The peak of milk production (6.79 ± 0.68 kg) was reached at 93.9 ± 55.8 days after calving. The open day (DO) and inter-calving interval (ICI) recorded in this study were 348.38 ± 30.33 and 723.38 ± 30.33 days, respectively. There is no significant difference (p > 0.05) between intensive and semi-intensive breeding systems for TMY (2795.39 ± 261.88 kg vs. 2580.89 ± 414.43 kg), DMY (6.96 ± 0.66 kg vs. 6.55 ± 1.00 kg), and LL (402.14 ± 21.18 days vs. 394 ± 21.03 days). However, the total amount of fat was significantly higher in intensive system (182.02 ± 33.91 kg) and the DPY content was significantly higher in semi-intensive system (4.60 ± 0.13%). The parameters α, ß, and γ of lactation, fat, and protein curves between the two systems showed a highly significant difference (p < 0.01) for the parameters (α and ß) for the milk production curve, significant (p < 0.05) for the time to reach peak yield, and no significance for the other parameters. The corresponding values of the coefficient of determination (R2) were 0.62, 0.35 for milk yield (p > 0.05), 0.12, 0.13 (p > 0.05) for fat, and 0.03, 0.11 (p < 0.05) for protein, in the intensive and semi-intensive systems, respectively. In addition, DO and ICI were not significantly different between the livestock systems, but were higher in the intensive system than the semi-intensive system (337.17 ± 26.26 vs. 712.17 ± 26.26, respectively). The study concluded that the intensive system had a higher milk performance with a more efficient lactation curve. The incomplete gamma model (Wood) used in this study was inappropriate for estimating milk yield, but acceptable for fat and protein.

Dairy goat performance in two grazing regimes: silvopastoral rangeland or abandoned agricultural land, and two supplementation treatments in central Mexico.

Twenty Saanen third parturition dairy goats were used in an on-farm 2 × 2 factorial arrangement that ran for 12 weeks, with two grazing regimes and two concentrate types. The grazing regimes evaluated were an extensive silvopastoral native rangeland (SPR) and grazing in an abandoned agricultural land (AAL). Grazing happened between 9:00 and 17:00 h. The two types of concentrate supplement were a high protein concentrate (HP = 180 g CP/kg DM and 13 MJ ME/kg DM) or high energy concentrate (HE = 110  g CP/kg DM and 14.3 MJ ME/kg DM). Goats were milked once a day, providing 250 g of concentrate supplement per goat and day. Animal variables were fat and protein corrected milk yield recorded every day, and milk composition determined for two consecutive days at the end of each experimental week. Flora in the experimental paddocks was characerised and sampled, including grasses, shrubs, trees, legumes and cacti. The data was analysed with the R software using a mixed model with day nested in period as random effect and goat as repeated measure. The SPR had greater (P = 0.002) fat and protein corrected milk yield than AAL, with no differences between concentrate type and no interaction (P > 0.05). There was an interaction (P < 0.01) between grazing regime and concentrate type for fat content in milk, where a reduction in fat content was notorious in the SPR regime. Protein content of milk was greater (P < 0.01) in SPR with no significant effects of concentrate type or the interaction. The number of plant species in SPR was greater. The native silvopastoral system supplemented with the high energy concentrate was the strategy with higher milk yield, and protein and milk fat content, although the interaction between grazing regime and supplement was significant only for milk fat content.

Nutritional factors affecting camel (Camelus dromedarius) milk composition.

Saharan population in Algeria still depending on bovine milk, which suffers from serious constraints undermining its sustainability. Camelus dromedarius milk has experienced growing demand following the emerging market requirements for livestock production and dairy farming over the past decade. The present work aimed at analysing the effect of nutritional regime on milk quality. The differences in pH, Acidity D°, Ash and Fats were significant. The pH was negatively influenced by the intensification conditions such as the much higher use of concentrates. The major constituents of milk were strongly and positively correlated with barley, wheat bran, TN/Kg.DM (Total Nitrogen/ Kg. Dry Matter), Kg.DM, Concentrates and daily watering. The results showed that a good energy-protein balance around 73 g PDI/UFL (Protein Digestible in the Intestine/Energetic Forage Unit for milk production) was beneficial for a better milk protein ratio. The use of corn, soybeans, palm dates and VM-premix (Vitamin Mineral) supplementation were also favourable to the synthesis of fats. Crude fiber and cell walls were better valued in the synthesis of fats with the availability of concentrates and the increasing of TN /Kg.DM and VM-premix rate in dietary regime. The vitamin C content elevate following high ratio of UFL /Kg.DM and PDI/UFL. For thus, the influence of nutritional status can lead to major improvements that need also more advanced and detailed studies.

Patterns of variation and relationships among fat, protein, and milk yield of individual dairy cattle in a Thai multibreed population.

This study systematically examines the patterns of milk yield (MY, kg), fat (FAT, %), and protein (PROT, %) in a diverse population of Thai multibreed dairy cattle, considering the tropical environment's impact on lactating cows. Using a dataset of 47,205 monthly test-day records from 4,440 first-lactation cows across 446 farms, we analyze variations and interrelationships through mathematical averaging and introduce the fat-to-protein ratio (FPR) to assess acidosis (FPR < 1.1) and ketosis (FPR > 1.5) risks during lactation. Pearson correlation analysis elucidated trait associations. The findings, aligned with established lactation norms, indicate peak production at 297 days in milk (DIM) for FAT (4.08%; SD = 0.96%), PROT (3.43%; SD = 0.47%), and 52 DIM for MY (18.09 kg; SD = 4.91 kg). Nadirs are observed at 72 DIM for FAT (3.27%; SD = 0.74%), 47 DIM for PROT (2.86%; SD = 0.36%), and 299 DIM for MY (9.05 kg; SD = 2.95 kg). FPR variations highlight acidosis (46.48%), normal (43.66%), and ketosis (9.86%), especially during early lactation (100 DIM). Significant negative correlations emerge between MY, FAT, and PROT (P < 0.05), while a positive correlation is identified between FAT and PROT (P < 0.01), with robust correlations during early lactation. This study contributes to understanding tailored nutritional strategies for dairy cows' holistic health and sustainability in tropical environments, guiding efficient production practices and mitigating health-related productivity impediments.

Specific Milk Composition of miR-30b Transgenic Mice Associated with Early Duodenum Maturation in Offspring with Lasting Consequences for Growth.

BACKGROUND: Milk composition is complex and includes numerous components essential for offspring growth and development. In addition to the high abundance of miR-30b microRNA, milk produced by the transgenic mouse model of miR-30b-mammary deregulation displays a significantly altered fatty acid profile. Moreover, wild-type adopted pups fed miR-30b milk present an early growth defect. OBJECTIVE: This study aimed to investigate the consequences of miR-30b milk feeding on the duodenal development of wild-type neonates, a prime target of suckled milk, along with comprehensive milk phenotyping. METHODS: The duodenums of wild-type pups fed miR-30b milk were extensively characterized at postnatal day (PND)-5, PND-6, and PND-15 using histological, transcriptomic, proteomic, and duodenal permeability analyses and compared with those of pups fed wild-type milk. Milk of miR-30b foster dams collected at mid-lactation was extensively analyzed using proteomic, metabolomic, and lipidomic approaches and hormonal immunoassays. RESULTS: At PND-5, wild-type pups fed miR-30b milk showed maturation of their duodenum with 1.5-fold (P < 0.05) and 1.3-fold (P < 0.10) increased expression of Claudin-3 and Claudin-4, respectively, and changes in 8 duodenal proteins (P < 0.10), with an earlier reduction in paracellular and transcellular permeability (183 ng/mL fluorescein sulfonic acid [FSA] and 12 ng/mL horseradish peroxidase [HRP], respectively, compared with 5700 ng/mL FSA and 90 ng/mL HRP in wild-type; P < 0.001). Compared with wild-type milk, miR-30b milk displayed an increase in total lipid (219 g/L compared with 151 g/L; P < 0.05), ceramide (17.6 µM compared with 6.9 µM; P < 0.05), and sphingomyelin concentrations (163.7 µM compared with 76.3 µM; P < 0.05); overexpression of 9 proteins involved in the gut barrier (P < 0.1); and higher insulin and leptin concentrations (1.88 ng/mL and 2.04 ng/mL, respectively, compared with 0.79 ng/mL and 1.06 ng/mL; P < 0.01). CONCLUSIONS: miR-30b milk displays significant changes in bioactive components associated with neonatal duodenal integrity and maturation, which could be involved in the earlier intestinal closure phenotype of the wild-type pups associated with a lower growth rate.

Dairy products and constituents: a review of their effects on obesity and related metabolic diseases.

Obesity has become a global public health problem that seriously affects the quality of life. As an important part of human diet, dairy products contain a large number of nutrients that are essential for maintaining human health, such as proteins, peptides, lipids, vitamins, and minerals. A growing number of epidemiological investigations provide strong evidence on dairy interventions for weight loss in overweight/obese populations. Therefore, this paper outlines the relationship between the consumption of different dairy products and obesity and related metabolic diseases. In addition, we dive into the mechanisms related to the regulation of glucose and lipid metabolism by functional components in dairy products and the interaction with gut microbes. Lastly, the role of dairy products on obesity of children and adolescents is revisited. We conclude that whole dairy products exert more beneficial effect than single milk constituent on alleviating obesity and that dairy matrix has important implications for metabolic health.

Human milk: From complex tailored nutrition to bioactive impact on child cognition and behavior.

Human milk is a highly complex liquid food tailor-made to match an infant's needs. Beyond documented positive effects of breastfeeding on infant and maternal health, there is increasing evidence that milk constituents also impact child neurodevelopment. Non-nutrient milk bioactives would contribute to the (long-term) development of child cognition and behavior, a process termed 'Lactocrine Programming'. In this review we discuss the current state of the field on human milk composition and its links with child cognitive and behavioral development. To promote state-of-the-art methodologies and designs that facilitate data pooling and meta-analytic endeavors, we present detailed recommendations and best practices for future studies. Finally, we determine important scientific gaps that need to be filled to advance the field, and discuss innovative directions for future research. Unveiling the mechanisms underlying the links between human milk and child cognition and behavior will deepen our understanding of the broad functions of this complex liquid food, as well as provide necessary information for designing future interventions.

Urea molasses mineral block under various feeding systems improved nutrient digestibility, productive performance and blood biochemical profile of Yaks.

BACKGROUND: The study aimed to investigate the effect of urea molasses mineral blocks (UMMB) on nutrient digestibility, productive performance and blood biochemical profile of indigenous yaks under various feeding systems. A total of sixteen yaks were randomly divided into four groups (n = 4 animal per group) and offered the, following feeding systems: (A) stall feeding, (B), urea molasses mineral block (UMMB) + stall feeding, (C) yard feeding and (D) UMMB + yard feeding. Trial lasted for 40 days. RESULTS: Results showed that nutrients intake (g) and nutrient digestibility (%) of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE) and crude fiber (CF) were significantly higher (p < 0.05) in stall and yard feeding groups with UMMB licking. Blood zinc, cobalt, hemoglobin (Hb), red blood cell (RBC), glucose and serum glutamate private transaminase (SGPT) significantly (p < 0.05) increased in stall and yard feeding with UMMB licking. Milk yield, Ca and monounsaturated fatty acid except milk composition improved significantly (p < 0.05) in stall and yard feeding groups with UMMB licking. CONCLUSION: It was concluded that feeding of UMMB improved utilization of low-quality roughages and best results were obtained from stall and yard feedings with UMMB licking as compared to other groups.

Potential role of rumen bacteria in modulating milk production and composition of admixed dairy cows.

Cattle milk is an important food for the growing calf and humans because of its concentrated macro and micro nutrients. However, the quantity and quality of milk nutrients vary depending on several factors. This study evaluated the effect of dietary modification on rumen bacteria as well as the potential role of rumen bacteria in modifying milk production and composition profile. Using a 16S rRNA metagenomic approach, the study characterized the rumen bacterial community composition in four dairy cows and their milk production and composition. The results indicated that Bacteroidetes and Firmicutes were the dominant bacteria, totaling ∼83.7% of the rumen bacteria. An increase in concentrate proportion in diet led to an increase in the abundance of Bacteroidetes (P ≤ 0.05) and Proteobacteria while Firmicutes and Fibrobacter decreased. Milk production and composition were highly correlated with the abundance of various rumen bacterial members. Lentispaerae (P = 0.010), and Synergistetes (P = 0.011) exhibited a positive and significant correlation while Tenericutes (P = 0.009) showed a negative correlation with milk protein. Fusobacteria (P = 0.016) showed a negative correlation with milk lactose. Similarly, several genera showed correlations with milk parameters. The correlation between microbes with milk parameters implies that the bacterial community possesses the potential to influence milk production and composition.

Genetic analysis of milk and milk composition traits in Murrah buffaloes using Bayesian inference.

Accurate and unbiased assessment of genetic parameters of milk and milk composition traits play an important role in formulating breeding program for genetic improvement of Murrah buffaloes. In this study, data spread over 28 years were utilized to estimate genetic parameters of traits viz., 305 d milk yield (305MY), 305 d fat yield (305FY), 305 d solid not fat yield (305SNFY), milk fat percentage (fat%) and solid not fat percentage (SNF) percentage (SNF%) in Murrah buffaloes kept at ICAR-National Dairy Research Institute, Karnal. Bayesian multiple-trait analysis was done using animal model and Gibbs sampling to estimate (co)variance components. Posterior means of heritability and posterior standard deviation for 305MY, 305FY, 305SNFY, fat% and SNF% were 0.18 ± 0.05, 0.17 ± 0.05, 0.18 ± 0.05, 0.07 ± 0.03 and 0.15 ± 0.06 and posterior means of repeatability estimates along with posterior standard deviation for corresponding traits were 0.33 ± 0.04, 0.32 ± 0.04, 0.33 ± 0.04, 0.14 ± 0.02 and 0.30 ± 0.04, respectively. Estimates of genetic correlation varied from -0.080 (305MY and fat %) to 0.999 (305MY and 305SNFY). Permanent environmental correlations varied from -0.060 (305MY and SNF%) to 0.999 (305FY and 305SNFY). This study indicated that all considered traits except fat% have ample genetic variability which can be exploited for selection and genetic improvement of Murrah buffaloes.