Feeding a Saccharomyces cerevisiae fermentation product during a gut barrier challenge in lactating Holstein cows impacts the ruminal microbiota and metabolome.

Through its influence on the gut microbiota, feeding of Saccharomyces cerevisiae fermentation products (SCFP) has been a successful strategy to enhance the health of dairy cows during periods of physiological stresses. Although production and metabolic outcomes from feeding SCFP are well-known, combined impacts on the ruminal microbiota and metabolome during gut barrier challenges remain unclear. To address this gap in knowledge, multiparous Holstein cows (97.1 ± 7.6 DIM; n = 8/group) fed a control diet (CON) or CON plus 19 g/d SCFP for 9 wk were subjected to a feed restriction (FR) challenge for 5 d, during which they were fed 40% of their ad-libitum intake from the 7 d before FR. DNA extracted from ruminal fluid was subjected to PacBio Full-Length 16S rRNA gene sequencing, RT-PCR of 12 major ruminal bacteria, and metabolomics analysis of up to 189 metabolites via GC-MS. High-quality amplicon sequence analyses were performed with Targeted Amplicon Diversity Analysis (TADA), MicrobiomeAnalyst, PICRUSt2, and STAMP software, while metabolomics data were analyzed via MetaboAnalyst 5.0. Ruminal fluid metabolites from the SCFP group exhibited a greater α diversity Chao 1 (P = 0.03) and Shannon indices (P = 0.05), and the PLS-DA analysis clearly discriminated metabolite profiles between dietary groups. The abundance of CPla_4_termite_group, Candidatus_Saccharimonas, Oribacterium, and Pirellula genus in cows fed SCFP was greater. In the SCFP group, concentrations of ethanolamine, 2-amino-4,6-dihydroxypyrimidine, glyoxylic acid, serine, threonine, cytosine, stearic acid, and pyrrole-2-carboxylic acid were greater in ruminal fluid. Both Fretibacterium and Succinivibrio abundance were positively correlated with metabolites across various biological processes: gamma-aminobutyric acid, galactose, butane-2,3-diol, fructose, 5-amino pentanoic acid, ß-aminoisobutyric acid, ornithine, malonic acid, 3-hydroxy-3-methylbutyric acid, hexanoic acid, heptanoic acid, cadaverine, glycolic acid, ß-alanine, 2-hydroxybutyric acid, methyl alanine, and alanine. In the SCFP group, compared with CON, the mean proportion of 14 predicted pathways based on metabolomics data was greater, while 10 predicted pathways were lower. Integrating metabolites and upregulated predicted enzymes (NADP+-dependent glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, serine: glyoxylate aminotransferase, and D-glycerate 3-kinase) indicated that the pentose phosphate pathway and photorespiration pathway were most upregulated by SCFP. Overall, SCFP during FR led to alterations in ruminal microbiota composition and key metabolic pathways. Among those, there was a shift from the tricarboxylic acid (TCA) cycle to the glyoxylate cycle and nitrogenous base production was enhanced.

Residual feed intake is related to metabolic and inflammatory response during the preweaning period in Italian Simmental calves.

Residual Feed Intake (RFI) is defined as the difference between measured and predicted intake. Understanding its biological regulators could benefit farm profit margins. The most-efficient animals (M-Eff) have observed intake smaller than predicted resulting in negative RFI, whereas the least-efficient (L-Eff) animals have positive RFI. Hence, this observational study aimed at retrospectively comparing the blood immunometabolic profile in calves with divergent RFI during the preweaning period. Twenty-two Italian Simmental calves were monitored from birth through 60 d of age. Calves received 3 L of colostrum from their respective dams. From 2 to 53 d of age, calves were fed a milk replacer twice daily, whereas from 54 to 60 d (i.e., weaning) calves were stepped down to only one meal in the morning. Calves had ad libitum access to concentrate and intakes were recorded daily. The measurement of BW and blood samples were performed at 0, 1, 7, 14, 21, 28, 35, 45, 54, and 60 d of age. Calves were ranked and categorized as M-Eff or L-Eff according to the median RFI value. Median RFI was -0.06 and 0.04 kg of DMI/d for M-Eff and L-Eff, respectively. No evidence for group differences was noted for colostrum and plasma IgG concentrations. Although growth rate was not different, as expected, (0.67 kg/d [95% CI = 0.57-0.76] for both L-Eff and M-Eff) throughout the entire preweaning period (0-60 d), starter intake was greater in L-Eff compared with M-Eff calves (+36%). Overall, M-Eff calves had a greater gain-to-feed ratio compared with L-Eff calves (+16%). Plasma ceruloplasmin, myeloperoxidase, and reactive oxygen metabolites concentrations were greater in L-Eff compared with M-Eff calves. Compared with L-Eff, M-Eff calves had an overall greater plasma concentration of globulin, and γ-glutamyl transferase (indicating a better colostrum uptake) and Zn at 1 d. Retinol and urea were overall greater in L-Eff. The improved efficiency in nutrient utilization observed in M-Eff was paired with a lower grade of oxidative stress and systemic inflammation. L-Eff may have had greater energy expenditure to support the activation of the immune system.

Impact of a Saccharomyces cerevisiae fermentation product during an intestinal barrier challenge in lactating Holstein cows on ileal microbiota and markers of tissue structure and immunity.

Feeding a Saccharomyces cerevisiae fermentation product (SCFP; NutriTek, Diamond V, Cedar Rapids, IA) during periods of metabolic stress is beneficial to the health of dairy cows partially through its effect on the gut microbiota. Whether SCFP alters the ileal microbiota in lactating cows during intestinal challenges induced by feed restriction (FR) is not known. We used 16S rRNA sequencing to assess if feeding SCFP during FR to induce gut barrier dysfunction alters microbiota profiles in the ileum. The mRNA abundance of key genes associated with tissue structures and immunity was also detected. Multiparous cows (97.1 ±â€…7.6 days in milk (DIM); n = 7 per treatment) fed a control diet or the control plus 19 g/d NutriTek for 9 wk were subjected to an FR challenge for 5 d, during which they were fed 40% of their ad libitum intake from the 7 d before FR. All cows were slaughtered at the end of FR. DNA extracted from ileal digesta was subjected to PacBio Full-Length 16S rRNA gene sequencing. High-quality amplicon sequence analyses were performed with Targeted Amplicon Diversity Analysis and MicrobiomeAnalyst. Functional analysis was performed and analyzed using PICRUSt and STAMP. Feeding SCFP did not (P > 0.05) alter dry matter intake, milk yield, or milk components during FR. In addition, SCFP supplementation tended (P = 0.07) to increase the relative abundance of Proteobacteria and Bifidobacterium animalis. Compared with controls, feeding SCFP increased the relative abundance of Lactobacillales (P = 0.03). Gluconokinase, oligosaccharide reducing-end xylanase, and 3-hydroxy acid dehydrogenase were among the enzymes overrepresented (P < 0.05) in response to feeding SCFP. Cows fed SCFP had a lower representation of adenosylcobalamin biosynthesis I (early cobalt insertion) and pyrimidine deoxyribonucleotides de novo biosynthesis III (P < 0.05). Subsets of the Firmicutes genus, Bacteroidota phylum, and Treponema genus were correlated with the mRNA abundance of genes associated with ileal integrity (GCNT3, GALNT5, B3GNT3, FN1, ITGA2, LAMB2) and inflammation (AOX1, GPX8, CXCL12, CXCL14, CCL4, SAA3). Our data indicated that the moderate FR induced dysfunction of the ileal microbiome, but feeding SCFP increased the abundance of some beneficial gut probiotic bacteria and other species related to tissue structures and immunity.

Stressors, including limited access to feed, heat stress, transportation, and disease are factors that reduce integrity of the gut epithelial barrier in livestock. Feeding Saccharomyces cerevisiae fermentation products (SCFP) mitigated immunological, aflatoxin, and subclinical mastitis challenges, heat stress, and grain-based subacute ruminal acidosis indicating it also could alleviate gut damage. Microbiota profiling of ileal epithelium using 16S rRNA sequencing and bioinformatics revealed that Lactobacillales and Animalis abundance was greater in cows fed SCFP versus controls during a 5-d feed restriction to induce intestinal dysfunction. Some genera of Firmicutes, Bacteroidota phylum, and Treponema genus were correlated with mRNA abundance of genes associated with integrity and inflammation of ileal epithelium. Thus, feeding SCFP can increase the abundance of beneficial bacteria during a gut challenge.

Alginate Nanoencapsulated Synbiotic Composite of Pomegranate Peel Phytogenics and Multi-Probiotic Species as a Potential Feed Additive: Physicochemical, Antioxidant, and Antimicrobial Activities.

A synbiotic composed of alginate nanoencapsulated prebiotic (pomegranate peel phytogenics) and multi-species probiotics (Lactococcus lactis, Lactobacillus plantarum, Lactobacillus paracasei, and Saccharomyces cerevisiae) has been developed as a potential eco-friendly alternative to antibiotics. The physicochemical properties of the encapsulated synbiotic were evaluated, and its gastric and storage tolerance, as well as its antioxidant and antimicrobial activity, were tested and compared to that of the non-encapsulated synbiotic (free synbiotic). The results showed that the prebiotic pomegranate peel ethanolic extract contained seven phenolic compounds, with cinnamic being the most abundant (13.26 µL/mL). Sodium alginate-CaCl2 nanocapsules were effective in encapsulating 84.06 ± 1.5% of the prebiotic's phenolic compounds and 98.85 ± 0.57% of the probiotics. The particle size of the alginate-CaCl2 nanoencapsulated synbiotic was 544.5 nm, and the polydispersity index and zeta potential values were 0.593 and -12.3 mV, respectively. Thermogravimetric analysis showed that the alginate-CaCl2 nanoencapsulated synbiotic had high thermal stability at high temperatures, with only 2.31% of its weight being lost within the temperature range of 70-100 °C. The count of viable probiotics in the nanoencapsulated synbiotic was significantly higher than that in the free synbiotic after exposure to gastric acidity and storage for six months at room temperature. The percent inhibition values of the nanoencapsulated synbiotic and ascorbic acid (as a standard antioxidant) were comparable and significantly greater than those of the free synbiotic. The half-maximal inhibitory concentrations (IC50) of the nanoencapsulated synbiotic and ascorbic acid were significantly lower than those of the free synbiotic (3.96 ± 0.42 µg/mL and 4.08 ± 0.79 µg/mL for nanoencapsulated synbiotic and ascorbic acid, respectively, vs. 65.75 ± 2.14 µg/mL for free synbiotic). The nanoencapsulated synbiotic showed the highest significant antimicrobial activity against Escherichia coli (ATCC 8739). Both the nanoencapsulated and free synbiotics showed antimicrobial activity against Staphylococcus aureus (ATCC 6538), similar to that of gentamicin, although the nanoencapsulated synbiotic showed significantly higher inhibition activity compared to the free synbiotic. The nanoencapsulated synbiotic showed antimicrobial activity comparable to gentamicin against Pseudomonas aeruginosa (ATCC 90274), whereas the free synbiotic showed the least antimicrobial activity (p < 0.05). Both synbiotics showed significantly higher antimicrobial activity against Salmonella typhi (ATCC 6539) than gentamicin. Both synbiotics showed antifungal activity against Aspergillus niger and Aspergillus flavus, with a stronger effect observed for the nanoencapsulated synbiotic. However, the activity of both synbiotics was significantly lower than that of fluconazole (an antifungal drug).

Influence of Cobalt Source, Folic Acid, and Rumen-Protected Methionine on Performance, Metabolism, and Liver Tissue One-Carbon Metabolism Biomarkers in Peripartal Holstein Cows.

Vitamin B12 plays a role in the remethylation of homocysteine to Met, which then serves as a substrate for Met adenosyltransferase (MAT) to synthesize S-adenosylmethionine (SAM). We investigated effects of feeding two cobalt sources [Co-glucoheptonate (CoPro) or CoPectin, Zinpro Corp.], an experimental ruminally-available source of folic acid (FOA), and rumen-protected Met (RPM) on performance and hepatic one-carbon metabolism in peripartal Holstein cows. From -30 to 30 d around calving, 72 multiparous cows were randomly allocated to: CoPro, CoPro + FOA, CoPectin + FOA, or CoPectin + FOA + RPM. The Co treatments delivered 1 mg Co/kg of DM (CoPro or CoPectin), each FOA group received 50 mg/d FOA, and RPM was fed at 0.09% of DM intake (DMI). Milk yield and DMI were not affected. Compared with other groups, the percentage of milk protein was greater after the second week of lactation in CoPectin + FOA + RPM. Compared with CoPro or CoPro + FOA, feeding CoPectin + FOA or CoPectin + FOA + RPM led to a greater activity of MAT at 7 to 15 d postcalving. For betaine-homocysteine S-methyltransferase, CoPro together with CoPectin + FOA + RPM cows had greater activity at 7 and 15 d than CoPro + FOA. Overall, supplying FOA with CoPectin or CoPectin plus RPM may enhance S-adenosylmethionine synthesis via MAT in the liver after parturition. As such, these nutrients may impact methylation reactions and liver function.

Early life microbiota transplantation from highly feed-efficient broiler improved weight gain by reshaping the gut microbiota in laying chicken.

Starting phase of laying chicken life is the building stone for rearing and production stages. Since, fecal microbial transplantation (FMT) regulates the gut microbial diversity and affects the productive performance of the bird. The aim of this study is to evaluate the effect of FMT from feed-efficient broiler chicken could program the diversity of gut microbiota and growth of recipient native slow growing egg-laying chicks. For this, a total of 150 (one-day-old) Jing Hong chicks were randomly assigned into two groups, each group consisted of 5 replicates (n = 15 bird/ replicate). The control group (CON) and FMT recipient birds (FMT) fed on basal diet, the FMT group received an oral daily dose of FMT prepared from Cobb-500 chickens. The FMT performed from the 1d to 28d of age, through the experimental period, feed intake and body weight were recorded weekly. At the end of a 28-day trial, carcass traits were assessed and cecal samples were collected for microbiome assessment via 16S rRNA-based metagenomic analysis to characterize the diversity and functions of microbial communities. The data were statistically analyzed using R software. Body weight and body weight gain increased, and FCR decreased (p = 0.01) in FMT group. The relative abundance of Firmicutes and the Firmicutes/Bacteroidetes (F/B) ratio were increased due to FMT administration (p = 0.01). A higher relative abundance of Lactobacillus, Lactococcus, and Bifidobacterium were presented in the FMT group. Meanwhile, Enterococcus, Helicobacter, and Bacteroides were more abundant in the CON group (p < 0.01). Kyoto encyclopedia of genes and genomes (KEGG) pathways for microbial functions regarding amino acid metabolism, secondary metabolites biosynthesis, carbohydrate metabolism, energy metabolism, and enzyme families, cofactors, and vitamins were significantly annotated in the FMT group. Overall, FMT administration from the donor of highly feed-efficient broilers improved weight gain by reshaping a distinct gut microbiome, which may be related to the metabolism and health in the recipients laying chicks, providing new insight on the application of the FMT technique for early life programming of laying chickens.

Human Milk Oligosaccharides Impact Cellular and Inflammatory Gene Expression and Immune Response.

Human milk harbors complex carbohydrates, including human milk oligosaccharides (HMOs), the third most abundant component after lactose and lipids. HMOs have been shown to impact intestinal microbiota, modulate the intestinal immune response, and prevent pathogenic bacterial binding by serving as decoy receptors. However, the direct effect of HMOs on intestinal function and immunity remains to be elucidated. To address this knowledge gap, 21-day-old germ-free mice (C57BI/6) were orally gavaged with 15 mg/day of pooled HMOs for 7 or 14 days and euthanized at day 28 or 35. A set of mice was maintained until day 50 to determine the persistent effects of HMOs. Control groups were maintained in the isolators for 28, 35, or 50 days of age. At the respective endpoints, intestinal tissues were subjected to histomorphometric and transcriptomic analyses, while the spleen and mesenteric lymph nodes (MLNs) were subjected to flow cytometric analysis. The small intestine (SI) crypt was reduced after HMO treatment relative to control at days 28 and 35, while the SI villus height and large intestine (LI) gland depth were decreased in the HMO-treated mice relative to the control at day 35. We report significant HMO-induced and location-specific gene expression changes in host intestinal tissues. HMO treatment significantly upregulated genes involved in extracellular matrix, protein ubiquitination, nuclear transport, and mononuclear cell differentiation. CD4+ T cells were increased in both MLNs and the spleen, while CD8+ T cells were increased in the spleen at day 50 in the HMO group in comparison to controls. In MLNs, plasma cells were increased in HMO group at days 28 and 35, while in the spleen, only at day 28 relative to controls. Macrophages/monocytes and neutrophils were lower in the spleen of the HMO group at days 28, 35, and 50, while in MLNs, only neutrophils were lower at day 50 in the 14-day HMO group. In addition, diphtheria toxoid and tetanus toxoid antibody-secreting cells were higher in HMO-supplemented group compared to controls. Our data suggest that HMOs have a direct effect on gastrointestinal tract metabolism and the immune system even in the absence of host microbiota.

Association of residual feed intake with peripartal ruminal microbiome and milk fatty acid composition during early lactation in Holstein dairy cows.

Residual feed intake (RFI) is a moderately heritable trait of feed efficiency in dairy cows. The main objective of the present study was to assess potential differences in the ruminal microbiome, milk fatty acid (FA) composition, and plasma concentrations of glucose, nonesterified fatty acids (NEFA), and ß-hydroxybutyrate between the most (M-EFF) and the least efficient (L-EFF) dairy cows during early lactation. Forty-seven multiparous Holstein dairy cows with daily ad libitum access to a total mixed ration from 30 d before calving to 30 d in milk were used. Cows were retrospectively classified into M-EFF (i.e., low RFI, n = 29) and L-EFF (high RFI, n = 18) based on a linear regression model. Ruminal digesta and milk samples were collected from each cow at 15 and 30 d in milk for microbiome analysis using 16S rRNA gene sequencing. Microbiome sequencing data were analyzed with the QIIME 2 platform (http://qiime.org/), whereas the microbiome statistical analyses and visual explorations were performed using the web-based MicrobiomeAnalyst platform. Milk FA composition was measured via gas chromatography-mass spectrometry. The statistical model used in SAS 9.4 (SAS Institute Inc.) included RFI, time, and their interactions as fixed effects. The cor() function in R programming was used to determine Pearson correlations between relative abundance of significant bacteria and milk FA. Overall, daily milk yield did not differ due to RFI and averaged 42 ± 1.6 kg for L-EFF and 43 ± 1.3 kg for M-EFF cows. However, M-EFF cows had lower overall dry matter intake (14.9 ± 0.5 kg/d) compared with L-EFF cows (19.2 ± 0.6 kg/d). No incidence of clinical disease was recorded for cows in the study. Compared with L-EFF, overall glucose concentration was lower, whereas NEFA and ß-hydroxybutyrate concentrations were greater in M-EFF cows. Ruminal digesta from both RFI groups had similar bacterial composition, but differed in the relative abundance of some bacteria. Compared with L-EFF, M-EFF cows had greater relative abundance of Lachnospiraceae, Lachnoclostridium, Papillibacter, Desulfovibrio, Sphaerochaeta, Acetobacter, and Histophilus. In contrast, relative abundance of Bifidobacterium, Ruminiclostridium, Prevotellaceae, and Erysipelotrichaceae bacterium was lower in M-EFF cows. Compared with L-EFF, M-EFF cows had greater proportions of long-chain monounsaturated FA, including 16:1 trans-9, 16:1 cis-9, 17:1 trans-10, 17:1 cis-10, 18:1 cis-9, 18:1 cis-11, whereas proportions of medium-chain saturated and 16:0 were lower in M-EFF. Acetate-producing bacteria (Sphaerochaeta and Acetobacter) were positively and significantly correlated (r ≥ 0.24) with concentrations of 16:1 cis-9 and 17:1 cis-10, whereas Prevotellaceae was significantly and negatively correlated (r = -0.25) with these FA. Butyrate-producing bacterium (Papillibacter) had a significant negative correlation (r = -0.27) with concentration of 15:0. Overall, data suggested that feed-efficient cows have unique profiles of ruminal microbiota, some of which are correlated with concentrations of milk FA during early lactation.

Role of Human Milk Bioactives on Infants' Gut and Immune Health.

Exclusive human milk feeding of the newborn is recommended during the first 6 months of life to promote optimal health outcomes during early life and beyond. Human milk contains a variety of bioactive factors such as hormones, cytokines, leukocytes, immunoglobulins, lactoferrin, lysozyme, stem cells, human milk oligosaccharides (HMOs), microbiota, and microRNAs. Recent findings highlighted the potential importance of adding HMOs into infant formula for their roles in enhancing host defense mechanisms in neonates. Therefore, understanding the roles of human milk bioactive factors on immune function is critical to build the scientific evidence base around breastfeeding recommendations, and to enhance positive health outcomes in formula fed infants through modifications to formulas. However, there are still knowledge gaps concerning the roles of different milk components, the interactions between the different components, and the mechanisms behind health outcomes are poorly understood. This review aims to show the current knowledge about HMOs, milk microbiota, immunoglobulins, lactoferrin, and milk microRNAs (miRNAs) and how these could have similar mechanisms of regulating gut and microbiota function. It will also highlight the knowledge gaps for future research.

Human Milk-Fed Piglets Have a Distinct Small Intestine and Circulatory Metabolome Profile Relative to That of Milk Formula-Fed Piglets.

The impact of human milk (HM) feeding compared with cow's milk formula (MF) feeding on small intestinal and circulatory metabolome patterns has not been fully investigated. Therefore, 2-day-old male piglets were fed HM or MF (n = 26/group) from postnatal day 2 (PND 2) through 21 and were weaned to a solid diet until PND 51. The small intestine (gastrointestinal [GI]) contents, serum, and urine were collected from subsets of piglets at PND 21 and PND 51. Samples were subjected to primary metabolomics analyses at the West Coast Metabolomics Center, UC Davis. The metabolome data assessment and the statistical analyses were performed with MetaboAnalyst software. Compared with MF feeding, at PND 21, HM feeding resulted in a higher abundance of fucose in the jejunum and urine and a greater concentration of myo-inositol in serum. In HM-fed piglets, 1,5-anhydroglucitol was higher in the duodenum, serum, and urine at PND 21. Additionally, the HM group had higher levels of urinary kynurenic acid at PND 21. Correlations between bacterial genera and altered metabolites in ileum revealed that Turicibacter sp. and Campylobacter sp. were positively correlated with maltotriose and panose at PND 21, while ileal Campylobacter sp. was negatively correlated with fumaric acid. At PND 51, no significant metabolites were identified between HM and MF diet groups. The metabolites associated with the neonatal diets may serve as the substrates and signals that contribute to the physiological effects in HM and MF during infancy, with a subset reflecting diet-associated differences in microbial metabolism and ecology.IMPORTANCE Exclusive HM feeding for newborns is recommended at least for the first 6 months of life. However, when breastfeeding is not possible, MF is recommended as a substitute. Due to the challenges associated with sample collection from infants fed HM or MF, their gut metabolism is poorly understood. Thus, an established piglet model from our team was used to determine the metabolite profile in relation to host, diet, and microbiota. The current study is the first to provide novel insights across the small intestine metabolism and its association with circulatory metabolites in the HM group relative to the MF group at the weaning and postweaning period. Data also demonstrate that during the neonatal period, diet, host, and microbial metabolism contribute to the lumen and circulatory metabolite profile. Furthermore, small intestinal lumen metabolome can be tracked in the urine as a biomarker of dietary differences, which would be a useful tool for clinical interventions.

Perspective: The Role of Human Breast-Milk Extracellular Vesicles in Child Health and Disease.

Human breast milk (HM) contains multiple bioactive substances determining its impact on children's health. Extracellular vesicles (EVs) are a heterogeneous group of secreted nanoparticles that are present in HM and may be partially responsible for its beneficial effects. The precise roles and content of EVs in HM remain largely unknown. To examine this, we performed a short narrative review on the literature focusing on HM EVs to contextualize the available data, followed by a scoping review of MEDLINE and Embase databases. We identified 424 nonduplicate citations with 19 original studies included. In this perspective, we summarize the evidence around HM EVs, highlight some theoretical considerations based on existing evidence, and provide an overview of some challenges associated with the complexity and heterogeneity of EV research. We consider how the existing data from HM studies conform to the minimal information for studies of EVs (MISEV) guidelines. Across the studies a variety of research methods were utilized involving both bench-based and translational methods, and a range of different EV contents were examined including RNA, proteins, and glycopeptides. We observed a variety of health outcomes in these studies, including allergy and atopy, necrotizing enterocolitis, and HIV. While some promising results have been demonstrated, the heterogeneity in outcomes of interest, methodological limitations, and relatively small number of studies in the field make comparison between studies or further translational work problematic. To date, no studies have examined normative values of HM EVs in a large, diverse population or with respect to potentially important influencing factors such as timing (hind- vs. foremilk), stage (colostrum vs. mature milk), and infant age (preterm vs. term), which makes extrapolation from bench or "basic" research impossible. Future research should focus on addressing the current inadequacies in the literature and utilize MISEV guidelines to inform study design.

Neonatal Diet Impacts the Large Intestine Luminal Metabolome at Weaning and Post-Weaning in Piglets Fed Formula or Human Milk.

The impact of human milk (HM) or dairy milk-based formula (MF) on the large intestine's metabolome was not investigated. Two-day old male piglets were randomly assigned to HM or MF diet (n = 26/group), from postnatal day (PND) 2 through 21 and weaned to a solid diet until PND 51. Piglets were euthanized at PND 21 and PND 51, luminal contents of the cecum, proximal (PC) and distal colons (DC), and rectum were collected and subjected to metabolomics analysis. Data analyses were performed using Metaboanalyst. In comparison to MF, the HM diet resulted in higher levels of fatty acids in the lumen of the cecum, PC, DC, and rectum at PND 21. Glutamic acid was greater in the lumen of cecum, PC, and DC relative to the MF group at PND 21. Also, spermidine was higher in the DC and rectal contents of HM relative to MF at PND 21. MF diet resulted in greater abundances of amino acids in the cecal lumen relative to HM diet at PND 21. Additionally, several sugar metabolites were higher in various regions of the distal gut of MF fed piglets relative to HM group at PND 21. In contrast, at PND 51, in various regions there were higher levels of erythritol, maltotriose, isomaltose in HM versus MF fed piglets. This suggests a post weaning shift in sugar metabolism that is impacted by neonatal diet. The data also suggest that infant diet type and host-microbiota interactions likely influence the lower gut metabolome.

Formula Diet Alters the Ileal Metagenome and Transcriptome at Weaning and during the Postweaning Period in a Porcine Model.

Exclusive breastfeeding impacts the intestinal microbiome and is associated with a better immune function than is seen with milk formula (MF) feeding in infants and yet with mechanisms poorly defined. The porcine model was used to evaluate the impact of MF on ileum microbial communities and gene expression relative to human milk (HM)-fed piglets. Fifty-two Dutch Landrace male piglets were fed an isocaloric diet of either HM (n = 26) or MF (n = 26) from day 2 through day 21 of age and weaned to a solid diet until day 51. Eleven piglets from each group were euthanized at day 21, while the remaining piglets (HM, n = 15; MF, n = 15) were euthanized at day 51 to collect ileal epithelium (EP) scrapings and ileal (IL) tissues. The epithelial mucosa was subjected to shotgun metagenome sequencing, and EP and IL tissues were used for transcriptome analysis. On day 21, transcriptome data revealed that the levels of pathways involved in inflammation and apoptosis were significantly higher in MF piglets than in HM piglets, whereas the levels of tight junctions and pathogen detection systems were lower in MF piglets than in HM piglets. The MF impacts on the small intestine were maintained over the postweaning period (day 51) as indicated by higher levels of Dialister invisus bacteria and higher levels of expression of genes associated with inflammation and apoptosis pathways relative to HM group. The current study demonstrated that MF might impact local intestinal inflammation, apoptosis, and tight junctions and might suppress pathogen recognition in the small intestine compared with HM.IMPORTANCE Exclusive human milk (HM) breastfeeding for the first 6 months of age in infants is recommended to improve health outcomes during early life and beyond. When women are unable to provide sufficient HM, milk formula (MF) is often recommended as a complementary or alternative source of nutrition. Previous studies in piglets demonstrated that MF alters the gut microbiome and induces inflammatory cytokine production. The links between MF feeding, gut microbiome, and inflammation status are unclear due to challenges associated with the collection of intestinal samples from human infants. The current report provides the first insight into MF-microbiome-inflammation connections in the small intestine compared with HM feeding using a porcine model. The present results showed that, compared with HM, MF might impact immune function through the induction of ileal inflammation, apoptosis, and tight junction disruptions and likely compromised immune defense against pathogen detection in the small intestine relative to piglets that were fed HM.

Neonatal Diet Impacts Circulatory miRNA Profile in a Porcine Model.

microRNAs (miRNAs) are conserved non-coding small nucleotide molecules found in nearly all species and breastmilk. miRNAs present in breastmilk are very stable to freeze-thaw, RNase treatment, and low pH as they are protected inside exosomes. They are involved in regulating several physiologic and pathologic processes, including immunologic pathways, and we have demonstrated better immune response to vaccines in piglets fed with human milk (HM) in comparison to dairy-based formula (MF). To understand if neonatal diet impacts circulatory miRNA expression, serum miRNA expression was evaluated in piglets fed HM or MF while on their neonatal diet at postnatal day (PND) 21 and post-weaning to solid diet at PND 35 and 51. MF fed piglets showed increased expression of 14 miRNAs and decreased expression of 10 miRNAs, relative to HM fed piglets at PND 21. At PND 35, 9 miRNAs were downregulated in the MF compared to the HM group. At PND 51, 10 miRNAs were decreased and 17 were increased in the MF relative to HM suggesting the persistent effect of neonatal diet. miR-148 and miR-181 were decreased in MF compared to HM at PND 21. Let-7 was decreased at PND 35 while miR-199a and miR-199b were increased at PND 51 in MF compared to HM. Pathway analysis suggested that many of the miRNAs are involved in immune function. In conclusion, we observed differential expression of blood miRNAs at both PND 21 and PND 51. miRNA found in breastmilk were decreased in the serum of the MF group, suggesting that diet impacts circulating miRNA profiles at PND 21. The miRNAs continue to be altered at PND 51 suggesting a persistent effect of the neonatal diet. The sources of miRNAs in circulation need to be evaluated, as the piglets were fed the same solid diet leading up to PND 51 collections. In conclusion, the HM diet appears to have an immediate and persistent effect on the miRNA profile and likely regulates the pathways that impact the immune system and pose benefits to breastfed infants.

MicroRNA profiles were altered in neonatal piglet mammary glands following postnatal infant formula feeding.

Postnatal dietary modulation of microRNAs (miRNAs) and effects on miRNA-mRNA interactions in tissues remain unknown. This study aimed to investigate whether dietary factors (formula vs. breastfeeding) affect mammary miRNA expression and to determine if these changes are concurrent with developmental alterations of the mammary gland in neonatal piglets. Female Yorkshire/Duroc piglets were fed sow's milk or cow's milk- or soy-based infant formula (from postnatal day 2 to day 21; n=6/group). Differentially expressed miRNAs were determined using mammary miRNA profiling, followed by miRNA and mRNA expressions characterized by quantitative reverse-transcription polymerase chain reaction. Milk and soy formulas reduced expressions of miR-1, -128, -133a, -193b, -206 and -27a; miRNA down-regulation altered mRNA expressions of genes (e.g., Ccnd1, Tgfb3, Igf1r and Tbx3) that were consistent with enhanced cell proliferation and suppressed apoptotic processes in the developing mammary gland. Interestingly, down-regulation of miR-1, -128 and -27a also correlated with increased mRNA genes such as Hmgcs and Hmgcr encoding cholesterol synthesis in the mammary glands in response to lower circulating cholesterol levels. Infant formula feeding affected mammary miRNA profiles in neonatal piglets, concurrent with increased expression of cell proliferation and cholesterol synthesis genes, suggesting early nutritional modulation of miRNAs may contribute to regulation of proliferative status and cholesterol homeostasis of developing mammary glands during infancy.

Nutrigenomic effect of conjugated linoleic acid on growth and meat quality indices of growing rabbit.

Conjugated linoleic acid was detected in rabbit caecotrophs, due to the presence of microbial lipid activity in rabbit cecum. However, the effect of CLA as a functional food in growing rabbit is not well established. Therefore, this study was conducted to determine the effect of CLA on production, meat quality, and its nutrigenomic effect on edible parts of rabbit carcass including skeletal muscle, liver, and adipose tissue. Therefore, seventy five weaned V-Line male rabbits, 30 days old, were randomly allocated into three dietary treatments receiving either basal control diet, diet supplemented with 0.5% (CLAL), or 1% CLA (CLAH). Total experimental period (63 d) was segmented into 7 days adaptation and 56 days experimental period. Dietary supplementation of CLA did not alter growth performance, however, the fat percentage of longissimus lumborum muscle was decreased, with an increase in protein and polyunsaturated fatty acids (PUFA) percentage. Saturated fatty acids (SFA) and mono unsaturated fatty acids (MUFA) were not increased in CLA treated groups. There was tissue specific sensing of CLA, since subcutaneous adipose tissue gene expression of PPARA was downregulated, however, CPT1A tended to be upregulated in liver of CLAL group only (P = 0.09). In skeletal muscle, FASN and PPARG were upregulated in CLAH group only (P ≤0.01). Marked cytoplasmic vacuolation was noticed in liver of CLAH group without altering hepatocyte structure. Adipocyte size was decreased in CLA fed groups, in a dose dependent manner (P <0.01). Cell proliferation determined by PCNA was lower (P <0.01) in adipose tissue of CLA groups. Our data indicate that dietary supplementation of CLA (c9,t11-CLA and t10,c12- CLA) at a dose of 0.5% in growing rabbit diet produce rabbit meat rich in PUFA and lower fat % without altering growth performance and hepatocyte structure.

Hepatic betaine-homocysteine methyltransferase and methionine synthase activity and intermediates of the methionine cycle are altered by choline supply during negative energy balance in Holstein cows.

Although choline requirements are unknown, enhanced postruminal supply may decrease liver triacylglycerol (TAG) storage and increase flux through the methionine cycle, helping cows during a negative energy balance (NEB). The objective was to investigate effects of postruminal choline supply during NEB on hepatic activity of betaine-homocysteine methyltransferase (BHMT), methionine synthase (MTR), methionine adenosyltransferase, transcription of enzymes, and metabolite concentrations in the methionine cycle. Ten primiparous rumen-cannulated Holstein cows (158 ± 24 d postpartum) were used in a replicated 5 × 5 Latin square design with 4-d treatment periods and 10 d of recovery (14 d/period). Treatments were unrestricted intake with abomasal infusion of water (A0), restricted intake (R; 60% of net energy for lactation requirements to induce NEB) with abomasal infusion of water (R0) or R plus abomasal infusion of 6.25, 12.5, or 25 g/d of choline ion. Liver tissue was collected on d 5 after the infusions ended, blood on d 1 to 5, and milk on d 1 to 4. Statistical contrasts were A0 versus R0 (CONT1) and tests of linear (L), quadratic (Q), and cubic (C) effects of choline dose. Plasma choline increased with R (CONT1) and choline (L). Although R decreased milk yield (CONT1), choline increased milk yield and liver phosphatidylcholine (PC), but decreased TAG (L). No differences were observed in plasma PC or very-low-density lipoprotein concentrations with R or choline. Activity and mRNA abundance of BHMT were greater with R (CONT1) and increased with choline (L). Although activity of MTR was lower with R (CONT1), it tended to increase with choline (L). No effect of R was detected for activity of methionine adenosyltransferase, but it changed cubically across dose of choline. Those responses were associated with linear increases in the concentrations of liver tissue (+13%) and plasma methionine concentrations. The mRNA abundance of CPT1A, SLC22A5, APOA5, and APOB, genes associated with fatty acid oxidation and lipoprotein metabolism, was upregulated by choline (Q). Overall, enhanced supply of choline during NEB increases hepatic activity of BHMT and MTR to regenerate methionine and PC, partly to help clear TAG. The relevance of these effects during the periparturient period merits further research.

RAPID COMMUNICATION: Residual feed intake in beef cattle is associated with differences in protein turnover and nutrient transporters in ruminal epithelium.

Residual feed intake (RFI) is a widely used measure of feed efficiency in cattle. Although the precise biologic mechanisms associated with improved feed efficiency are not well-known, most-efficient steers (i.e., with low RFI coefficient) downregulate abundance of proteins controlling protein degradation in skeletal muscle. Whether cellular mechanisms controlling protein turnover in ruminal tissue differ by RFI classification is unknown. The aim was to investigate associations between RFI and signaling through the mechanistic target of rapamycin (MTOR) and ubiquitin-proteasome pathways in ruminal epithelium. One hundred and forty-nine Red Angus cattle were allocated to 3 contemporary groups according to sex and herd origin. Animals were offered a finishing diet for 70 d to calculate the RFI coefficient for each. Within each group, the 2 most-efficient (n = 6) and least-efficient animals (n = 6) were selected. Compared with least-efficient animals, the most-efficient animals consumed less feed (P < 0.05; 18.36 vs. 23.39 kg/d DMI). At day 70, plasma samples were collected for insulin concentration analysis. Ruminal epithelium was collected immediately after slaughter to determine abundance and phosphorylation status of 29 proteins associated with MTOR, ubiquitin-proteasome, insulin signaling, and glucose and amino acid transport. Among the proteins involved in cellular protein synthesis, most-efficient animals had lower (P ≤ 0.05) abundance of MTOR, p-MTOR, RPS6KB1, EIF2A, EEF2K, AKT1, and RPS6KB1, whereas MAPK3 tended (P = 0.07) to be lower. In contrast, abundance of p-EEF2K, p-EEF2K:EEF2K, and p-EIF2A:EIF2A in most-efficient animals was greater (P ≤ 0.05). Among proteins catalyzing steps required for protein degradation, the abundance of UBA1, NEDD4, and STUB1 was lower (P ≤ 0.05) and MDM2 tended (P = 0.06) to be lower in most-efficient cattle. Plasma insulin and ruminal epithelium insulin signaling proteins did not differ (P > 0.05) between RFI groups. However, abundance of the insulin-responsive glucose transporter SLC2A4 and the amino acid transporters SLC1A3 and SLC1A5 also was lower (P ≤ 0.05) in most-efficient cattle. Overall, the data indicate that differences in signaling mechanisms controlling protein turnover and nutrient transport in ruminal epithelium are components of feed efficiency in beef cattle.