Association of residual feed intake with abundance of ruminal bacteria and biopolymer hydrolyzing enzyme activities during the peripartal period and early lactation in Holstein dairy cows

Abstract Background Residual feed intake (RFI) in dairy cattle typically calculated at peak lactation is a measure of feed efficiency independent of milk production level. The objective of this study was to evaluate differences in ruminal bacteria, biopolymer hydrolyzing enzyme activities, and overall performance between the most- and the least-efficient dairy cows during the peripartal period. Twenty multiparous Holstein dairy cows with daily ad libitum access to a total mixed ration from d − 10 to d 60 relative to the calving date were used. Cows were classified into most-efficient (i.e. with low RFI, n = 10) and least-efficient (i.e. with high RFI, n = 10) based on a linear regression model involving dry matter intake (DMI), fat-corrected milk (FCM), changes in body weight (BW), and metabolic BW. Results The most-efficient cows had ~ 2.6 kg/d lower DMI at wk 4, 6, 7, and 8 compared with the least-efficient cows. In addition, the most-efficient cows had greater relative abundance of total ruminal bacterial community during the peripartal period. Compared with the least-efficient cows, the most-efficient cows had 4-fold greater relative abundance of Succinivibrio dextrinosolvens at d − 10 and d 10 around parturition and tended to have greater abundance of Fibrobacter succinogenes and Megaspheara elsdenii. In contrast, the relative abundance of Butyrivibrio proteoclasticus and Streptococcus bovis was lower and Succinimonas amylolytica and Prevotella bryantii tended to be lower in the most-efficient cows around calving. During the peripartal period, the most-efficient cows had lower enzymatic activities of cellulase, amylase, and protease compared with the least-efficient cows. Conclusions The results suggest that shifts in ruminal bacteria and digestive enzyme activities during the peripartal period could, at least in part, be part of the mechanism associated with better feed efficiency in dairy cows

Rumen-protected methionine during the peripartal period in dairy cows and its effects on abundance of major species of ruminal bacteria

Abstract Background Extensive degradation of amino acids in the rumen via microbial deamination decreases the post-ruminal availability of dietary indispensable amino acids. Together with the normal decrease in voluntary dry matter intake (DMI) around parturition in dairy cows, microbial metabolism contributes to a markedly negative balance of indispensable amino acids, including methionine which may be the first-limiting for milk production. The main objective of the current study was to profile changes in major bacterial species with key functions in cellulose and hemicellulose digestion, xylan breakdown, proteolytic action, propionic acid production, lactate utilization and ruminal biohydrogenation in cows supplemented with rumen-protected Methionine (SM; Smartamine M, Adisseo NA, Alpharetta, GA, USA) from −23 through 30 d relative to parturition. Because ~90% of the methionine in SM bypasses the rumen, ~10% of the methionine is released into the rumen and can be utilized by microbes. Results As expected, there was an increase in overall DMI after parturition (Day, P < 0.05) during which cows consumed on average 19.6 kg/d versus 13.9 kg/d in the prepartum period. The postpartum diet contained greater concentrations of lipid and highly-fermentable carbohydrate from corn grain, which likely explains the increases in the relative abundance of Anaerovibrio lipolytica, Megasphaera elsdenii, Prevotella bryantii, Selenomonas ruminantium, Streptococcus bovis, and Succinimonas amylolytica. Despite similar DMI prepartum, cows fed SM had greater (Treatment × Day, P < 0.05) abundance prepartum of Fibrobacter succinogenes, Succinimonas amylolytica, and Succinivibrio dextrinosolvens. However, the greater DMI in cows fed SM after parturition (19.6 kg/d versus 13.9 kg/d) was associated with lower abundance of Fibrobacter succinogenes (2.13 × 10−3 versus 2.25 × 10−4) and Selenomonas ruminantium (2.98 × 10−1 versus 4.10 × 10−1). A lower abundance (Day, P < 0.05) was detected on d 20 compared with d −10 for Fibrobacter succinogenes and Succinivibrio dextrinosolvens. The relative abundance of Butyrivibrio proteoclasticus and Eubacterium ruminantium was stable across treatment and time. Conclusions In diets with proper balance of rumen-degradable protein and fermentable carbohydrate, the small fraction of Methionine released from the rumen-protected supplement did not seem to compromise growth of major bacterial species in the rumen. In fact, it had a positive effect on 3 major species prepartum when DMI was similar between groups. Because the actual requirements of Methionine (and Lysine, for example) by the cow during the transition period are unknown, it appears warranted to study the rumen microbiome as it relates to supply of rumen-protected amino acids

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

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

Protective Effect of Date Pits on Growth Performance, Carcass Traits, Blood Indices, Intestinal Morphology, Nutrient Digestibility, and Hepatic Aflatoxin Residues of Aflatoxin B1-Exposed Broilers

This research aimed to assess the influence of date pits (DP) on reducing toxic influences of aflatoxin B1 (AFB1) in broilers by examining the growth performance, carcass characteristics, serum indices, ileum morphology, apparent nutrient digestibility, and liver AFB1 residues. In total, 360 11-day-old straight-run broilers (Ross 308) were randomly allocated into 6 dietary treatments, with 10 replications of 6 birds each, in a 20-day experiment. The treatments were as follows: standard basal diet (negative control, NC); NC + 0.25 mg/kg AFB1 (positive control, PC); NC + 2% DP; NC + 4% DP; PC + 2% DP; PC + 4% DP. Compared to the NC diet, feeding the PC diet decreased the daily feed intake (DFI) during the grower and overall periods (p p p p p p < 0.001). To conclude, our findings demonstrate that a dietary addition of 4% DP can deliver a better safeguard against the adverse influences of AFB1 in broiler chickens

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

Hepatic expression responses of DNA methyltransferases, heat shock proteins, antioxidant enzymes, and NADPH 4 to early life thermal conditioning in broiler chickens

Early-life thermal conditioning (TC) in broiler chickens has long-lasting impacts on later life. Therefore, this study aimed to clarify the molecular mechanism by which TC impacts the hepatic expression heat shock proteins (hsps), antioxidant enzymes, NADPH oxidase 4 (NOX4), glucocorticoid receptor (GR), and DNA methyltransferases genes in broiler chicks at five weeks of age. Two hundred forty one-day-old male broiler chicks of Cobb 500 were allocated into four equal experimental groups. The first group was under the optimal brooding conditions (control), whereas the 2nd, 3rd, and 4th groups were exposed to TC at 39 ± 1 °C for six hours on the third-, fifth- or seventh-day post-hatch, respectively. At 35 days of age, all chicks of four experimental groups were subjected to heat challenge by exposure to 36 ± 1 °C for six hours. Results showed that broilers exposed to TC on the fifth-day post-hatch when exposed to acute heat stress at five weeks of age had the lowest plasma CORT level, the lowest expression (p < .05) for NOX4, GR, SOD, SOD2, and CAT among all groups. The same trend was observed for hsp70, hsp90A, hsp90B, hsp60, and hspA9. In conclusion, early thermal conditioning on the fifth-day post-hatch may improve thermotolerance by decreasing NOX4 and GR expressions, leading to reduced heat shock proteins and antioxidant enzyme gene expression subsequently reduced oxidative stress.Highlights Thermal conditioning is a promising approach to mitigate heat stress in broiler chicks. The optimal age to perform thermal conditioning is a controversial issue. Heat shock proteins gene expression and plasma corticosterone are good indicators for thermotolerance acquisition. Thermal conditioning on the fifth-day post-hatch reduced oxidative stress at five weeks of age

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

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