The role of dietary nucleotides in single-stomached animals

Autolyzed yeast and sodium butyrate supplemented alone to diets promoted improvements in performance, intestinal health and nutrient transporter in weaned piglets

This study investigated the effects of supplemental nucleotides, autolyzed yeast (Saccharomyces cerevisiae), and sodium butyrate in diets for nursery pigs on growth performance, diarrhea incidence, blood profile, intestinal morphology, mRNA expression of nutrient transporters, inflammatory markers, antioxidant profile, and tight junction proteins in the small intestine. One hundred eighty 21-day-old pigs (5.17 ± 0.57 kg) were assigned in a randomized block design to 1 of 4 dietary treatments: (1) CON: control, basal diet, (2) NUC: CON + nucleotides, (3) YSC: CON + lysed yeast S. cerevisiae, (4) ASB: CON + acidifier sodium butyrate. Pigs were fed for 24 days, phase 1 (21-32 days) and 2 (32-45 days). During phase 1, YSC and ASB improved average daily gain (ADG) and feed conversion (FC) compared with CON. At the overall period, ASB improved ADG and YSC improved FC compared with CON. The NUC diet did not affect growth performance. The ASB increased ileal villus height compared to CON. The YSC and ASB reduced the number of Peyer's patches in the ileum compared with CON. The YSC increased mRNA expression of nutrient transporters (SMCT2, MCT1, and PepT1), tight junction proteins (OCL and ZO-1), antioxidants (GPX), and IL1-β in the jejunum compared with CON. The ASB increased mRNA expression of nutrient transporters (SGLT1 and MCT1), tight junction proteins (OCL and ZO-1), and antioxidants (GPX and SOD) compared with CON. In conclusion, autolyzed yeast and sodium butyrate promoted growth performance by improving the integrity of the intestinal barrier, the mRNA expression of nutrient transporters, and antioxidant enzymes in the jejunum of nursery pigs whereas supplementation of nucleotides did not show such effects.

Plasma Metabolites and Life's Simple 7 in REGARDS

BACKGROUND

The American Heart Association's Life's Simple 7 (LS7) is a health metric that captures important factors associated with cardiovascular and cerebrovascular health. Previous studies highlight the potential of plasma metabolites to serve as a marker for lifestyle and health behavior that could be a target for stroke prevention. The objectives of this study were to identify metabolites that were associated with LS7 and incident ischemic stroke and mediate the relationship between the two.

METHODS

Targeted metabolomic profiling of 162 metabolites by liquid chromatography-tandem mass spectrometry was used to identify candidate metabolites in a stroke case-cohort nested within the REGARDS study (Reasons for Geographic and Racial Differences in Stroke). Weighted linear regression and weighted Cox proportional hazard models were used to identify metabolites that were associated with LS7 and incident ischemic stroke, respectively. Effect measures were based on a 1-SD change in metabolite level. Metabolite mediators were examined using inverse odds ratio weighting mediation analysis.

RESULTS

The study comprised 1075 ischemic stroke cases and 968 participants in the random cohort sample. Three out of 162 metabolites were associated with the overall LS7 score including guanosine (β, -0.46 [95% CI, -0.65 to -0.27]; P=2.87×10-6), cotinine (β, -0.49 [95% CI, -0.70 to -0.28]; P=7.74×10-6), and acetylneuraminic acid (β, -0.59 [95% CI, -0.77 to -0.42]; P=4.29×10-11). Guanosine (hazard ratio, 1.47 [95% CI, 1.31-1.65]; P=6.97×10-11), cotinine (hazard ratio, 1.30 [95% CI, 1.16-1.44]; P=2.09×10-6), and acetylneuraminic acid (hazard ratio, 1.29 [95% CI, 1.15-1.45]; P=9.24×10-6) were associated with incident ischemic stroke. The mediation analysis identified guanosine (27% mediation, indirect effect; P=0.002), cotinine (30% mediation, indirect effect; P=0.004), and acetylneurminic acid (22% mediation, indirect effect; P=0.041) partially mediated the relationship between LS7 and ischemic stroke.

CONCLUSIONS

We identified guanosine, cotinine, and acetylneuraminic acid that were associated with LS7, incident ischemic stroke, and mediated the relationship between LS7 and ischemic stroke.

Assessing the impact of three feeding stages on rumen bacterial community and physiological characteristics of Japanese Black cattle

In Japan, Japanese Black cattle, known for their exceptional meat quality owing to their abundant intramuscular fat, undergo a unique three-stage feeding system with varying concentrate ratios. There is limited research on physiological and rumen microbial changes in Japanese Black cattle during these stages. Therefore, this study aimed to examine Japanese Black steers in these three stages: early (T1, 12-14 months), middle (T2, 15-22 months), and late (T3, 23-30 months). The rumen bacteria of 21 cattle per phase was analyzed using 16S rRNA gene sequencing. Rumen bacterial diversity was significantly higher in T1, with a distinct distribution, than in T2 and T3. Specific phyla and genera were exclusive to each stage, reflecting the shifts in feed composition. Certain genera dominated each stage: T1 had Flexilinea, Streptococcus, Butyrivibrio, Selenomonas, and Kandleria; T2 had Bifidobacterium, Shuttleworthia, and Sharpea; and T3 had Acetitomaculum, Mycoplasma, Atopobium, and Howardella. Correlation analysis revealed significant associations between certain microbial populations and physiological parameters. These findings indicate that changes in energy content and feed composition are associated with physiological and ruminal alterations. This study may guide strategies to improve rumen health and productivity in Japanese Black cattle by modifying diets to specific fattening stages.

Growth Performance, Metabolomics, and Microbiome Responses of Weaned Pigs Fed Diets Containing Growth-Promoting Antibiotics and Various Feed Additives

The objective of this study was to determine the potential biological mechanisms of improved growth performance associated with potential changes in the metabolic profiles and intestinal microbiome composition of weaned pigs fed various feed additives. Three separate 42 day experiments were conducted to evaluate the following dietary treatments: chlortetracycline and sulfamethazine (PC), herbal blends, turmeric, garlic, bitter orange extract, sweet orange extract, volatile and semi-volatile milk-derived substances, yeast nucleotide, and cell wall products, compared with feeding a non-supplemented diet (NC). In all three experiments, only pigs fed PC had improved (p < 0.05) ADG and ADFI compared with pigs fed NC. No differences in metabolome and microbiome responses were observed between feed additive treatments and NC. None of the feed additives affected alpha or beta microbiome diversity in the ileum and cecum, but the abundance of specific bacterial taxa was affected by some dietary treatments. Except for feeding antibiotics, none of the other feed additives were effective in improving growth performance or significantly altering the metabolomic profiles, but some additives (e.g., herbal blends and garlic) increased (p < 0.05) the relative abundance of potentially protective bacterial genera that may be beneficial during disease challenge in weaned pigs.

Effects of ribonucleotide supplementation in modulating the growth of probiotic Bacillus subtilis and the synergistic benefits for improving the health performance of Asian seabass (Lates calcarifer)

In aquaculture, due to the requirements for high-density culture, the diseases caused by bacterial pathogens have become a serious issue. To solve this problem, we performed synbiotic application of RNA and Bacillus subtilis as a sustainable and eco-friendly approach to improve the health and immunity of Asian seabass (Lates calcarifer) during cultivation without using any harmful antibiotics or chemicals. Among various forms of nucleic acids, such as mononucleotides and DNA, RNA was found to be most effective in promoting the growth performance of probiotic B. subtilis in all the tested minimal medium conditions. Accordingly, we used the synbiotic combination of B. subtilis and RNA for Asian seabass cultivation. After feed supplementation for fourteen days, the fish that received the combination treatment exhibited a significant increase in innate cellular and humoral immune parameters, including phagocytic activity, phagocytic index, respiratory burst, serum lysozyme and bactericidal activities, as well as upregulated expression of immune-related genes, including HEPC1, A2M, C3, CC, CLEC, LYS, HSP70, and HSP90. Furthermore, significant increases were observed in the ileal villus height and goblet cell numbers in the intestinal villi in all fish treatment groups. The combination treatment did not cause histopathological abnormalities in the intestine and liver, suggesting that the synbiotic treatment is safe for use in fish. The treated Asian seabass also exhibited a significantly increased survival rate after Aeromonas hydrophila challenge. These results indicate that the synbiotic mixture of B. subtilis and RNA can be considered a beneficial feed additive and immunostimulant for Asian seabass cultivation.

Stress Reduction Potential in Mice Ingesting DNA from Salmon Milt

The functionality of food-derived nucleotides is revealed when nucleotide components are ingested in emergency situations, such as during stress loading, though it is difficult to elucidate the physiological function of dietary nucleotide supplementation. Using a stress load experimental system utilizing territoriality among male mice, we evaluated whether DNA sodium salt derived from salmon milt (DNA-Na) has stress-relieving effects. It was found that stress was reduced in mice fed a diet containing a 1% concentration of DNA-Na, but this was insignificant for yeast-derived RNA. Next, we attempted to elucidate the anti-stress effects of DNA-Na using another experimental system, in which mice were subjected to chronic crowding stress associated with aging: six mice in a cage were kept until they were 7 months of age, resulting in overcrowding. We compared these older mice with 2-month-old mice that were kept in groups for only one month. The results show that the expression of genes associated with hippocampal inflammation was increased in the older mice, whereas the expression of these genes was suppressed in the DNA-Na-fed group. This suggests that dietary DNA intake may suppress inflammation in the brain caused by stress, which increases with age.

Dietary inclusion of methanotrophic microbial cell-derived protein in the early post-weaning period sustains growth performance and intestinal health of weaner piglets

The global demand for sustainably produced protein feeds for animal production is increasing. Methanotrophic bacteria grow on methane and convert it into microbial cell protein (MCP) that has been shown to have high nutritive value for growing pigs. The present aimed to investigate how increasing amounts of MCP in diets fed during the first 15 days after weaning affect the growth performance of piglets from weaning until day 43 postweaning. Furthermore, the effect of MCP on intestinal morphology and histopathology was assessed on day 15 after weaning. During seven consecutive weeks, approximately 480 piglets were recruited for the experiment per batch. The piglets were divided into four groups and housed in eight double pens with 60 piglets per pen. The piglets were fed one of four experimental diets with 0, 3, 6, or 10% of MCP included at the expense of fishmeal and subsequently potato protein for the first 15 days postweaning. Thereafter, all pigs were fed commercial weaner diets in two phases (days 16-30 and days 31-43) until day 43 postweaning. All diets were without medicinal zinc. Feed intake and growth were registered on double pen level during all three phases. On day 15 after weaning, 10 piglets per treatment were randomly selected, autopsied, and sampled for intestinal morphology and histopathology. Daily gain during the first 15 days postweaning tended (P = 0.09) to be affected by the inclusion of MCP in the weaning diet being lowest in the group fed 10% MCP. Treatment did not affect daily feed intake; however, Feed Conversion Ratio (FCR) was significantly affected (P = 0.003) showing the highest FCR in piglets fed 10% MCP. Growth performance was not affected by the experimental treatment during the following phases. In the small intestine, villous height tended (P = 0.09) to show a quadratic response to level of MCP in the diet with the longest villi observed after feeding 6% MCP. Dietary treatment did not affect crypt depth. The villous height to crypt depth (VC) ratio showed a quadratic response to increased dietary inclusion of MCP (P = 0.02) with piglets fed 6% MCP having the highest VC ratio. In conclusion, this study demonstrated that MCP could constitute 6% of diets as-fed (22% of total CP), at the expense of fishmeal and potato protein, for newly weaned piglets without negative effects on growth rates and FCR. The inclusion of MCP in diets for newly weaned piglets could be part of improving the sustainability of pig production.

Effects of dietary adenosine and adenosine 5′-monophosphate supplementation on carcass characteristics, meat quality, and lipid metabolism in adipose tissues of finishing pigs

This study investigated the effects of adenosine (ADO) and adenosine 5'-monophosphate (AMP) supplementation on the growth performance, carcass characteristics, meat quality, and lipid metabolism in adipose tissues of finishing pigs. The pigs were allocated to three treatment groups: the control diet, 0.2%ADO diet, or 0.2%AMP diet. Compared with CON group (CON), both ADO and AMP groups increased in carcass straight length (P < 0.05) and decreased in drip loss (P < 0.05), while AMP group tended to increase in redness value (P = 0.05) and decreased in free amino acid content in longissimus thoracis (LT) muscle (P < 0.05). Additionally, ADO or AMP supplementation increased the ADO or AMP content in serum, adipose tissue, and LT muscle (P < 0.05), as well as the protein level of adenosine 2A receptor (A2a) in adipose tissue (P < 0.05). Moreover, both ADO and AMP groups showed an increase in the expression of lipolysis genes (ATGL and HSL) in adipose tissue (P < 0.05). Overall, AMP supplementation could improve meat quality, and ADO and AMP supplementation regulate the lipid metabolism of finishing pigs.

Plasma Metabolites Link Dietary Patterns to Stroke Risk

OBJECTIVE

While dietary intake is linked to stroke risk, surrogate markers that could inform personalized dietary interventions are lacking. We identified metabolites associated with diet patterns and incident stroke in a nested cohort from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study.

METHODS

Levels of 162 metabolites were measured in baseline plasma from stroke cases (n = 1,198) and random controls (n = 904). We examined associations between metabolites and a plant-based diet pattern previously linked to reduced stroke risk in REGARDS. Secondary analyses included 3 additional stroke-associated diet patterns: a Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Southern diet. Metabolites were tested using Cox proportional hazards models with incident stroke as the outcome. Replication was performed in the Jackson Heart Study (JHS). Inverse odds ratio-weighted mediation was used to determine whether metabolites mediated the association between a plant-based diet and stroke risk.

RESULTS

Metabolites associated with a plant-based diet included the gut metabolite indole-3-propionic acid (β = 0.23, 95% confidence interval [CI] [0.14, 0.33], p = 1.14 × 10-6 ), guanosine (β = -0.13, 95% CI [-0.19, -0.07], p = 6.48 × 10-5 ), gluconic acid (β = -0.11, 95% CI [-0.18, -0.04], p = 2.06 × 10-3 ), and C7 carnitine (β = -0.16, 95% CI [-0.24, -0.09], p = 4.14 × 10-5 ). All of these metabolites were associated with both additional diet patterns and altered stroke risk. Mediation analyses identified guanosine (32.6% mediation, p = 1.51 × 10-3 ), gluconic acid (35.7%, p = 2.28 × 10-3 ), and C7 carnitine (26.2%, p = 1.88 × 10-2 ) as mediators linking a plant-based diet to reduced stroke risk.

INTERPRETATION

A subset of diet-related metabolites are associated with risk of stroke. These metabolites could serve as surrogate markers that inform dietary interventions. ANN NEUROL 2023;93:500-510.

Dietary nucleotides influences intestinal barrier function, immune responses and microbiota in 3-day-old weaned piglets

Nucleotides (NTs) play a pivotal role in the growth and development of the intestine. This study aimed to evaluate the effects of nucleotides supplementation on the intestinal barrier function, immune responses and microbiota in 3-day-old weaned piglets. Ninety-six piglets weaned at 3-days after birth were randomly assigned to 2 treatments (6 replicates/treatment, 8 piglets/replicate) according to the average body weight. The dietary treatments consisted of the control (CON; fed a basal artificial milk) and nucleotides groups (NT; fed a basal artificial milk with 0.035 % nucleotides, the contents of CMP, UMP, AMP, GMP, and IMP were 1:1:1:1:1, respectively). Diarrhea rates were recorded, and blood and intestinal samples were collected on day 35 of the piglets. The current study showed that NTs supplementation tended to decrease the diarrhea rate of weaned piglets (P < 0.10). NTs increased villus height and the villus height-to-crypt depth (V/C) ratio in the ileum (P < 0.05). Dietary NTs up-regulated protein expression of ZO-1 in ileal mucosa (P < 0.05), and the protein expression of Occludin tended to increase. Furthermore, NTs up-regulated the mRNA expression of Mucin (MUC)2, while the mRNA expression of MUC4 was down-regulated in the ileal mucosa (P < 0.05). Besides, supplementation with NTs increased the ileal mucosa genes expression of IL-21, INF-γ, IL-10, IL-4, IL-6 and TNF-α (P < 0.05). Furthermore, dietary NTs increased the protein expression of NF-κB, IL-6 and TNF-α (P < 0.05), and the proteins expression of Occludin and p-NF-κB tended to be up-regulated in the ileal mucosa (P < 0.10). Furthermore, NTs supplementation increased short chain fatty acid in the colonic (P < 0.05). And NTs supplementation reduced the Firmicutes/Bacteroidota ratio in the colon, at the genus level, NTs enriched the relative abundance of Prevotella, Faecalibacterium and Olsenella (P < 0.05). These data indicate that NTs could increase the villus height, increase the V/C, regulate the expression of tight junction protein and mucin, improve the intestinal barrier of piglets, regulate the secretion of cytokines, improve the biological immunity, increase the abundance of beneficial bacteria, and thus reduce the diarrhea of piglets.

Gastrointestinal dynamics, immune response, and nutrient digestibility of weanling pigs fed diets supplemented with enzymatically treated yeast1

The objective of this trial was to investigate the effect of enzymatically treated yeast (ETY) on the growth performance, nutrient digestibility, immune response, and gut health of weanling pigs. A total of 192 weanling pigs (6.0 ± 1.04 kg) were allocated to 4 corn and soybean-based diets with increasing concentrations of ETY (0, 1, 2, or 4 g/kg) for a 43-d trial. There were 8 replicate pens (4 replicate pens per sex) and 6 pigs per replicate. The experiment was set up as a randomized complete block design with body weight used as a blocking factor. Pigs had ad libitum access to water and diets for the duration of the study. There was no effect of ETY supplementation on the growth performance indices of weanling pigs. At day 14, there was a quadratic decrease (P < 0.05) in the apparent total tract digestibility (ATTD) of acid detergent fiber (ADF). At day 28, there was a linear increase (P < 0.05) in the ATTD of neutral detergent fiber and a quadratic decrease (P < 0.05) in the ATTD of ADF. On day 14, there was a linear increase (P < 0.05) in serum catalase activity with ETY supplementation. There was a linear increase (P < 0.01) in the gene expression of glutathione peroxidase-4 in the ileal mucosa of pigs. Increasing dietary ETY supplementation linearly decreased (P < 0.05) the gene expression of ileal peptide transporter 1. There was a tendency for a quadratic effect (P = 0.07) in the ileal villus height to crypt depth ratio with ETY supplementation. In addition, there was a tendency for a linear increase (P = 0.06) in ileal digesta butyrate with ETY supplementation. In conclusion, the current study demonstrated that dietary ETY supplementation could partly ameliorate the deleterious effects of post-weaning stress by enhancing the antioxidative status of weanling pigs. However, prolonged supplementation of ETY may be needed to see its effect on growth performance.

Uridine affects amino acid metabolism in sow-piglets model and increases viability of pTr2 cells

Background

As an important nucleoside precursor in salvage synthesis pathway of uridine monophosphate, uridine (UR) is the most abundant nucleotide in sow milk. This study aimed to investigate the effects of maternal UR supplementation during second trimester of gestation on reproductive performance and amino acid metabolism of Sows.

Results

Results showed that compared to CON group, the average number of stillborn piglets per litter was significantly reduced (P &lt; 0.05) with higher average piglet weight at birth in UR group (P = 0.083). Besides, dietary UR supplementation significantly increased TP in sow serum, BUN content in cord serum, and TP and ALB in newborn piglet serum (P &lt; 0.05); but decreased AST level in sow serum and BUN level in piglet serum (P &lt; 0.05). Importantly, free amino acids profile in sow serum newborn piglet serum and colostrum was changed by maternal UR supplementation during day 60 of pregnancy, as well as the expression of amino acids transporter (P &lt; 0.05). In addition, from 100 to 2,000 μM UR can increased the viability of pTr2 cells. The UR exhibited higher distribution of G1/M phase of cell cycle at 400 μM compared with 0 μM, and reduced S-phases of cell cycle compared with 0 and 100μM (P &lt; 0.05).

Conclusion

Supplementation of uridine during day 60 of pregnancy can improve reproductive performance, regulate amino acid metabolism of sows and their offspring, and increase the viability of pTr2 cells.

Yeast-Derived Products: The Role of Hydrolyzed Yeast and Yeast Culture in Poultry Nutrition—A Review

Simple Summary

Yeast and yeast-derived products are largely employed in animal nutrition to support animals’ health and to improve their performance. Thanks to their components, including mannans, β-glucans, nucleotides, vitamins, and other compounds, yeasts have numerous beneficial effects. Among yeast-derived products, hydrolyzed yeasts and yeast cultures have received less attention, but, although the results are somewhat conflicting, in most of the cases, the available literature shows improved performance and health in poultry. Thus, the aim of this review is to provide an overview of hydrolyzed-yeast and yeast-culture employment in poultry nutrition, exploring their effects on the production performance, immune response, oxidative status, gut health, and nutrient digestibility. A brief description of the main yeast bioactive compounds is also provided.

Abstract

Yeasts are single-cell eukaryotic microorganisms that are largely employed in animal nutrition for their beneficial effects, which are owed to their cellular components and bioactive compounds, among which are mannans, β-glucans, nucleotides, mannan oligosaccharides, and others. While the employment of live yeast cells as probiotics in poultry nutrition has already been largely reviewed, less information is available on yeast-derived products, such as hydrolyzed yeast (HY) and yeast culture (YC). The aim of this review is to provide the reader with an overview of the available body of literature on HY and YC and their effects on poultry. A brief description of the main components of the yeast cell that is considered to be responsible for the beneficial effects on animals’ health is also provided. HY and YC appear to have beneficial effects on the poultry growth and production performance, as well as on the immune response and gut health. Most of the beneficial effects of HY and YC have been attributed to their ability to modulate the gut microbiota, stimulating the growth of beneficial bacteria and reducing pathogen colonization. However, there are still many areas to be investigated to better understand and disentangle the effects and mechanisms of action of HY and YC.

Nucleosides Associated With Incident Ischemic Stroke in the REGARDS and JHS Cohorts

BACKGROUND AND OBJECTIVES

Both genetic and environmental factors contribute to stroke risk. We sought to identify novel metabolites associated with incident stroke in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort and determine whether they reflected genetic or environmental variation.

METHODS

This was a stroke case-cohort observational study nested in REGARDS. Cases were defined as incident stroke and metabolomic profiles were compared to a randomly selected control cohort. In baseline plasma samples, 162 metabolites were measured using liquid chromatography-tandem mass spectrometry. Cox proportional hazards models were adjusted for age, sex, race, and age by race in the base model. Fully adjusted models included traditional stroke risk factors. Mediation analyses conducted for these stroke risk factors used the metabolite as mediator. Genome-wide associations with the leading candidate metabolites were calculated using array data. Replication analyses in the Jackson Heart Study (JHS) were conducted using random effects meta-analysis.

RESULTS

There were 2,043 participants who were followed over an average period of 7.1 years, including 1,075 stroke cases and 968 random controls. Nine metabolites were associated with stroke in the base model, 8 of which were measured and remained significant in meta-analysis with JHS. In the fully adjusted model in REGARDS, guanosine (hazard ratio [HR] 1.34, 95% CI 1.18-1.53; p = 7.26 × 10^-6) and pseudouridine (HR 1.28, 95% CI 1.13-1.45; p = 1.03 × 10^-4) were associated with incident ischemic stroke following Bonferroni adjustment. Guanosine also partially mediated the relationship between hypertension and stroke (17.6%) and pseudouridine did not mediate any risk factor. Genome-wide association analysis identified loci rs34631560 and rs34631560 associated with pseudouridine, but these did not explain the association of pseudouridine with stroke.

DISCUSSION

Guanosine and pseudouridine are nucleosides associated with incident ischemic stroke independently of other risk factors. Genetic and mediation analyses suggest that environmental exposures rather than genetic variation link nucleoside levels to stroke risk.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that guanosine and pseudouridine are associated with incident stroke.

Profile of Nucleotides in Chinese Mature Breast Milk from Six Regions

This study measured the total potentially available nucleoside (TPAN) content in breast milk from six different regions of China as a part of the Maternal Nutrition and Infant Investigation (MUAI) study. A total of 631 breast milk samples were collected from healthy, lactating women with singleton, full-term pregnancies between 40 and 45 days postpartum in Changchun, Chengdu, Lanzhou, Shanghai, Tianjin, and Guangzhou. TPAN and free 5′-monophosphate nucleotide (5′-MNT) contents were determined by high-performance liquid chromatography. The TPAN content of the Chinese mature milk ranged from 11.61 mg/L to 111.09 mg/L, with a median level of 43.26 mg/L. Four types of nucleotides were identified, and the median levels of cytidine monophosphate (CMP), uridine monophosphate (UMP), guanosine monophosphate (GMP), and adenosine monophosphate (AMP) were 22.84 mg/L, 9.37 mg/L, 4.86 mg/L, and 4.80 mg/L, respectively. CMP was the predominant nucleotide, accounting for 52.9% of the TPAN content, while free 5′-MNT accounted for 18.38% of the TPAN content. The distribution pattern of the TPAN content and level of the individual nucleotides were significantly different among the selected regions (p < 0.05), but the result showed no significant differences in the TPAN level in breast milk (p > 0.05). In addition, no correlation was reported between the geographic distribution and TPAN levels. This result showed that TPAN better reflects the level of total potential nucleosides in Chinese breast milk rather than 5′-MNT in free form. CMP, UMP, GMP, and AMP are the only 4 types of nucleotides reported in all detections. In addition, results revealed a large variation of TPAN levels in Chinese breast milk across six regions, so that the median value may not be the optimal fortification level of TPAN for Chinese infant populations.

Dietary supplementation with inosine-5'-monophosphate improves the functional, energetic, and antioxidant status of liver and muscle growth in pigs

Inosine 5'-monophosphate (5'-IMP) is an essential nucleotide for de novo nucleotide biosynthesis and metabolism of energy, proteins, and antioxidants. Nucleotides are conditionally essential, as they cannot be produced sufficiently rapidly to meet the needs of the body in situations of oxidative stress or rapid muscle growth. A deficient intake of nucleotides can result in decreased ATP and GTP synthesis and impaired metabolism. We demonstrated that supplementation of finishing pig diets with 5'-IMP reduces the relative weight of the liver, and increases oxygen consumption during mitochondrial respiration without changing the ADP/O ratio, indicating an increase in the respiratory efficiency of liver mitochondria. We also observed a reduction in liver lipid peroxidation and an increase in muscle creatine. Moreover, 5'IMP supplementation increases slaughter weight, lean meat yield, sarcomere length, and backfat thickness in finishing barrows, demonstrating influence on protein metabolism. We suggest that 5'-IMP supplementation increase the mitochondrial respiratory capacity when the liver metabolic activity is stimulated, enhances antioxidant defense, and promotes muscle growth in finishing barrows.

Dietary Nucleotides Alleviate Hepatic Lipid Deposition via Exogenous AMP-Mediated AMPK Activation in Zebrafish

BACKGROUND

Dietary nucleotides (NTs) have been reported to affect hepatic function and composition. However, the effects on hepatic lipid deposition are less studied.

OBJECTIVES

We aimed to identify the regulatory role of dietary NTs in hepatic lipid deposition of zebrafish and elucidate the underlying mechanisms.

METHODS

Zebrafish (60 ± 1.69 mg; 1 mo old) were fed control diet (16.2% energy as fat) or diet supplemented with 0.1% NTs or 0.02% AMP in feeding experiments 1 and 2. Experiment 3 was conducted with zebrafish larvae. In experiment 4, 1-mo-old zebrafish were fed a high-fat diet (HFD, 38.2% energy as fat) or an HFD supplemented with 0.1% NTs or 0.02% AMP. Hepatic lipid deposition was evaluated by triglyceride (TG) content and staining. Phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) was assayed by immunoblotting. Zebrafish liver (ZFL) cells were treated with exogenous adenosine. Small interfering RNA was used to knock down AMPK or nucleoside transporter SLC28a1 in ZFL cells. Vivo-morpholino was used to knock down AMPK in zebrafish larvae.

RESULTS

Dietary 0.1% NTs or 0.02% AMP reduced hepatic TGs by 62% and 32%, respectively, compared with control (P < 0.05). Dietary AMP enhanced hepatic AMPK and ACC phosphorylation. Consistently, exogenous adenosine enhanced AMPK and ACC phosphorylation by 111% and 53%, respectively, in ZFL cells (P < 0.01) and reduced TG content by 56% (P < 0.05). Knockdown of AMPK and SLC28a1 abolished the effect of adenosine on lipid deposition in ZFL cells, and AMPK morpholino blocked the hepatic lipid-lowering effect of dietary AMP in vivo. Finally, dietary NTs and AMP activated AMPK and attenuated hepatic lipid deposition (28% and 30%, P < 0.05) in fish fed an HFD.

CONCLUSIONS

Dietary NTs and AMP reduce hepatic lipid deposition in zebrafish, which involves exogenous AMP-mediated AMPK activation. Our results suggest that dietary NTs can contribute to alleviation of hepatic steatosis.

Uric acid extrarenal excretion: the gut microbiome as an evident yet understated factor in gout development

Humans do not produce uricase, an enzyme responsible for degrading uric acid. However, some bacteria residing in the gut can degrade one-third of the dietary and endogenous uric acid generated daily. New insights based on metagenomic and metabolomic approaches provide a new interest in exploring the involvement of gut microbiota in gout. Nevertheless, the exact mechanisms underlying this association are complex and have not been widely discussed. In this study, we aimed to review the evidence that suggests uric acid extrarenal excretion and gut microbiome are potential risk factors for developing gout. A literature search was performed in PubMed, Web of Science, and Google Scholar using several keywords, including "gut microbiome AND gout". A remarkable intestinal dysbiosis and shifts in abundance of certain bacterial taxa in gout patients have been consistently reported among different studies. Under this condition, bacteria might have developed adaptive mechanisms for de novo biosynthesis and salvage of purines, and thus, a concomitant alteration in uric acid metabolism. Moreover, gut microbiota can produce substrates that might cross the portal vein so the liver can generate de novo purinogenic amino acids, as well as uric acid. Therefore, the extrarenal excretion of uric acid needs to be considered as a factor in gout development. Nevertheless, further studies are needed to fully understand the role of gut microbiome in uric acid production and its extrarenal excretion, and to point out possible bacteria or bacterial enzymes that could be used as probiotic coadjutant treatment in gout patients.

The Impact of Weaning Stress on Gut Health and the Mechanistic Aspects of Several Feed Additives Contributing to Improved Gut Health Function in Weanling Piglets-A Review

Simple Summary

The current review aimed to provide an overview on the problems associated with weaning with a special focus on gut health, and also highlighted the nutritional approach using different kinds of feed additives and their mechanistic aspects in mitigating production inefficiencies and gut health dysfunction in weanling pigs.

Abstract

Newly weaned pig encounters psychosocial, physical, and nutritional stressors simultaneously when their immune system is not fully developed. These stressors have a cumulative effect on the immune response that contributes to the post-weaning growth lag which is characterized by depression in feed intake, reduced or negative growth rates, and increased susceptibility to pathogens in the first 24 to 48 h post-weaning. Consequently, the intestinal integrity, and digestive and absorptive capacity are impaired, and there is an increase in intestinal oxidative stress. It also causes the shifts in the taxonomic and functional properties of intestinal microbiome abruptly, thereby adversely affecting the health and performance of animals. It has been suggested that the effects of weaning stress on immune functions, intestinal barrier functions, and nervous system function in early weaned pigs extends into adulthood. The inclusion of different types of feed additives into the diet have been reported to alleviate the negative effects of weaning stress. The objective of this paper was to provide an overview on how the weaning stress affects gut health and the impact it has on production efficiencies, as well as the mechanistic aspects of several feed additives applied in reducing the weaning associated gut health problems and performance inefficiencies.

Investigation of Early Supplementation of Nucleotides on the Intestinal Maturation of Weaned Piglets

Simple Summary

Nucleotides represent a group of bioactive compounds essential for the development of the gastrointestinal tract and immune function. This study aimed to evaluate the short-term effect of oral administration of nucleotides before and after weaning on growth performance, health, development of the intestinal immunity and microbiome of piglet. A nucleotide-based product (NU) was orally given four times before weaning and once after to one group of piglets, while a second group was used as a control (CO). The NU pigs did not grow more than the control until 12 days post-weaning but had increased hemoglobin and hematocrit values. At weaning, feces of NU piglets had a microbial profile more typical of growing pigs, while those of CO were more representative of suckling pigs. The upregulation of genes in the blood of control pigs at weaning was indicative of more activation towards an inflammatory response, while genes of erythropoiesis were more active in NU pigs post-weaning. NU supplementation stimulated genes for proliferative activity in the intestinal immune system, a sign of possible anticipated maturation. NU supplementation did not influence the growth performance of piglets but may have expressed a positive effect on pig microbiota anticipating its maturation at weaning, with possible immunostimulant activity on the intestinal immune system.

Abstract

Nucleotides are essential for the development of the gastrointestinal tract and immune function, but their intake with milk by piglets could be insufficient. The effect of nucleotides on growth and health was tested on 98 piglets divided into two groups: NU, orally administrated with 4 mL of a nucleotide-based product (SwineMOD^®) at 10, 15, 18, 21, 27 days, or not (CO). Blood and feces were sampled at weaning (26 d, T1), and at 38 d (T2). Per each group and time-point, eight piglets were slaughtered and jejunal Peyer’s patches (JPPs) were collected. NU increased hemoglobin content and hematocrit, but not growth. At weaning, the NU fecal microbiota was characterized by the abundance of Campylobacteraceae, more typical of the growing phase, compared to CO, with a greater abundance of Streptococcaceae. For the blood transcriptome, an initial greater inflammatory activation was seen in CO, while at T2, NU enriched gene sets related to erythropoiesis. The activation of gene groups ranging from epigenetic response to transcriptional regulation evidenced an intense proliferative activity in NU JPPs. NU supplementation did not influence the growth performance of piglets but could have expressed a positive effect on pig microbiota anticipating its maturation at weaning. This immunostimulant activity in the JPPs could moderate the inflammation in the immediate pre-weaning.

Intestinal Health of Pigs Upon Weaning: Challenges and Nutritional Intervention

The primary goal of nursery pig management is making a smooth weaning transition to minimize weaning associated depressed growth and diseases. Weaning causes morphological and functional changes of the small intestine of pigs, where most of the nutrients are being digested and absorbed. While various stressors induce post-weaning growth depression, the abrupt change from milk to solid feed is one of the most apparent challenges to pigs. Feeding functional feed additives may be viable solutions to promote the growth of nursery pigs by enhancing nutrient digestion, intestinal morphology, immune status, and by restoring intestinal balance. The aim of this review was to provide available scientific information on the roles of functional feed additives in enhancing intestinal health and growth during nursery phase. Among many potential functional feed additives, the palatability of the ingredient and the optimum supplemental level are varied, and these should be considered when applying into nursery pig diets. Considering different stressors pigs deal with in the post-weaning period, research on nutritional intervention using a single feed additive or a combination of different additives that can enhance feed intake, increase weight gain, and reduce mortality and morbidity are needed to provide viable solutions for pig producers. Further research in relation to the feed palatability, supplemental level, as well as interactions between different ingredients are needed.

Management and Feeding Strategies in Early Life to Increase Piglet Performance and Welfare around Weaning: A Review

The performance of piglets in nurseries may vary depending on body weight, age at weaning, management, and pathogenic load in the pig facilities. The early events in a pig's life are very important and may have long lasting consequences, since growth lag involves a significant cost to the system due to reduced market weights and increased barn occupancy. The present review evidences that there are several strategies that can be used to improve the performance and welfare of pigs at weaning. A complex set of early management and dietary strategies have been explored in sows and suckling piglets for achieving optimum and efficient growth of piglets after weaning. The management strategies studied to improve development and animal welfare include: (1) improving sow housing during gestation, (2) reducing pain during farrowing, (3) facilitating an early and sufficient colostrum intake, (4) promoting an early social interaction between litters, and (5) providing complementary feed during lactation. Dietary strategies for sows and suckling piglets aim to: (1) enhance fetal growth (arginine, folate, betaine, vitamin B12, carnitine, chromium, and zinc), (2) increase colostrum and milk production (DL-methionine, DL-2-hydroxy-4-methylthiobutanoic acid, arginine, L-carnitine, tryptophan, valine, vitamin E, and phytogenic actives), (3) modulate sows' oxidative and inflammation status (polyunsaturated fatty acids, vitamin E, selenium, phytogenic actives, and spray dried plasma), (4) allow early microbial colonization (probiotics), or (5) supply conditionally essential nutrients (nucleotides, glutamate, glutamine, threonine, and tryptophan).

Digestible and metabolizable energy concentrations and amino acid digestibility of dried yeast and soybean meal for growing pigs

Energy values and amino acid (AA) digestibility of dried yeast (DY) and soybean meal (SBM) were determined in 2 experiments with growing pigs. Experiment 1 was conducted to determine the digestible energy (DE) and metabolizable energy (ME) in DY and SBM. Thirty barrows with a mean initial body weight (BW) of 20.6 kg (SD = 1.04) were assigned to 5 dietary treatments in a randomized complete block design with period and BW as blocking factors. A reference diet was prepared with corn, canola meal, and soybean oil as energy-contributing ingredients. Four additional diets were prepared by adding 5% and 10% DY or SBM at the expense of energy-contributing ingredients in the reference diet. The ratio of corn, canola meal, and soybean oil was kept consistent across the experimental diets. Each experimental period consisted of 5-d adaptation and 5-d quantitative collection of feces and urine. Test ingredient-associated DE or ME intake (kcal/d) was regressed against test ingredient intake [kg dry matter (DM)/d] to estimate the DE or ME in test ingredients as the slope of linear regression model. The DE in DY was estimated at 3,933 kcal/kg DM, which was not different from the estimated DE in SBM at 4,020 kcal/kg DM. Similarly, there was no difference between DY and SBM in the estimated ME (3,431 and 3,756 kcal/kg DM, respectively). Experiment 2 was conducted to determine the standardized ileal digestibility (SID) of AA in DY and SBM. Twenty-one barrows with a mean initial BW of 20.0 kg (SD = 1.31) were surgically fitted with T-cannulas at the distal ileum and assigned to 3 dietary treatments in a randomized complete block design with BW as a blocking factor. Two semi-purified diets containing DY or SBM as the sole nitrogen source and one nitrogen-free diet (NFD) were prepared. The NFD was used to estimate the basal ileal endogenous losses of CP and AA. Pigs were fed the 3 diets for 5 d as adaptation, followed by 2 d of feeding with ileal digesta collection. The SID of AA, except Gly and Pro, in DY was less (P < 0.05) than in SBM. The SID of indispensable AA in DY ranged from 64.1% for Thr to 85.2% for Arg, and those in SBM ranged from 83.9% for Thr to 91.8% for Arg. In conclusion, energy values of DY are not different from those of SBM, whereas AA in DY is less digestible than in SBM. The estimated DE and ME as well as the SID of AA in DY and SBM can be used in diet formulation for growing pigs using these ingredients.

Effects of dietary supplementation of nucleotides from late gestation to lactation on the performance and oxidative stress status of sows and their offspring

Increased metabolic burdens in breeding sows, which are induced by elevated systemic oxidative stress, could increase the need for nucleotides to repair lymphocyte DNA damage; however, de novo synthesis of nucleotides may be insufficient to cover this increased need. This study investigated the effects of dietary nucleotides on milk composition, oxidative stress status, and the reproductive and lactational performance of sows. Forty multiparous sows were assigned to 2 dietary treatments (Control group, and 1 g/kg Nucleotides group) based on a randomized complete block design using their BW at 85 d of gestation as a block. Sows from 2 groups were fed a restricted diet during gestation and ad libitum during lactation. The experiment lasted from 85 d of gestation to 21 d of lactation. The reproductive performance of sows and the growth performance of suckling piglets were measured. Oxidative stress parameters and milk components were also analysed. Data were analyzed using contrasts in the MIXED procedure of SAS. Sows in the Nucleotides group consumed more feed during the first week (P < 0.01) and from 1 to 21 d (P < 0.05) of lactation than those in Control group. Correspondingly, the litter weight gain of piglets showed a tendency to increase from cross-fostering to 9 d (P = 0.09) and from cross-fostering to 20 d (P = 0.10) in the Nucleotides group relative to the Control group. Additionally, the Nucleotides group was higher (P < 0.01) than the Control group in the concentrations of uridine 5'monophosphate, guanosine 5'monophosphate, inosine 5'monophosphate, adenosine 5'monophosphate and total nucleotides in milk. Furthermore, the Nucleotides group was higher (P < 0.01) than the Control group in the serum levels of total antioxidant capacity (P < 0.01) for sows at 109 d of gestation and glutathione peroxidase for weaning piglets, but lower at the levels of thiobarbituric acid-reactive substances (P < 0.05) in serum of weaning piglets. This study indicated that maternal dietary nucleotides could promote piglet growth, probably due to the higher lactational feed intake and higher concentration of nucleotides in the milk of sows, and lower oxidative stress for both sows and piglets.

Dietary nucleotide supplementation as an alternative to in-feed antibiotics in weaned piglets

Nucleotides are important to cell growth and division and are crucial to the rapid proliferation of such cells as the intestinal mucosa and immune cells. Accordingly, the nucleotide requirements of animals are high during periods of rapid growth and periods of stress like post-weaning period. Thus, nucleotide supplementation may be a possible alternative to in-feed antibiotics as growth promoter in this phase. The study aimed to evaluate dietary nucleotide supplementation as an alternative to in-feed antibiotics on performance and gut health of weaned piglets. Ninety-six 21-day-old piglets, weighing 7.44 ± 0.65 kg, were allocated into 1 of 3 treatments (8 pens per treatment; 4 pigs per pen) in a 14-day trial. Dietary treatments consisted of control: corn-soybean meal-based diet; nucleotides: control +2 g/kg of a nutritional additive with purified nucleotides; and antibiotic: control +0.8 g/kg of antibiotic growth promoter based on colistin and tylosin. Performance variables and fecal score were not affected (P > 0.05) by supplementing nucleotide or antibiotic. Nucleotides treatment had similar effect to antibiotic and superior to control (P < 0.05) on enhancing duodenum villus height, jejunum crypt depth, and reduction of Paneth cellular area. Duodenum and ileum of animals supplemented with nucleotides or antibiotics had higher (P < 0.05) number of proliferating cells than did those of control animals, whereas the jejunum of animals that received antibiotic diets presented more (P < 0.05) proliferating cells than either the nucleotides or control animals. Jejunum of nucleotide-treated piglets showed a greater number of apoptotic cells than those fed antibiotic or control diets (P < 0.05). Nucleotides and antibiotic treatments decreased the B lymphocyte counts in duodenum and ileum (P < 0.05) but increased in the jejunum (P < 0.05), when compared to the control treatment. Relative abundance of mitogen-activated protein kinases-6, haptoglobin, and tumor necrosis factor-α mRNA was not influenced (P > 0.05) by treatments. In the ileal, antibiotic supplementation reduced total bacteria quantification compared to nucleotide supplementation or the control (P < 0.05), whereas nucleotides supplementation increased enterobacteria proliferation compared to the antibiotic or control diets (P < 0.05). However, nucleotides and antibiotic reduced (P < 0.05) colon total bacteria quantification when compared to control. These results suggest that the nucleotides source used to weaned piglets improved gut health by modulating the local immune response and modulating intestinal mucosa development, and, therefore, nucleotides may be an alternative to antibiotics as growth promoters.

Dietary supplementation with hydrolyzed yeast and its effect on the performance, intestinal microbiota, and immune response of weaned piglets

The objective of this study was to evaluate the effects of autolyzed yeast on performance, cecal microbiota, and leukogram of weaned piglets. A total of 96 piglets of commercial line weaned at 21-day-old were used. The experimental design was a randomized block design with four treatments (diets containing 0.0%, 0.3%, 0.6%, and 0.9% autolyzed yeast), eight replicates, and three animals per pen in order to evaluate daily weight gain, daily feed intake, and feed conversion in periods of 0 to 15, 0 to 26, and 0 to 36 days. Quadratic effects of autolyzed yeast inclusion were observed on the feed conversion from 0 to 15 days, on daily weight gain from 0 to 15 days, 0 to 26 days and, 0 to 36 days, indicating an autolyzed yeast optimal inclusion level between 0.4% and 0.5%. No effect from autolyzed yeast addition was observed on piglet daily feed intake, cecal microbiota, and leukogram; however, i.m. application of E. coli lipopolysaccharide reduced the values ​​of total leukocytes and their fractions (neutrophils, eosinophils, lymphocytes, monocytes, and rods). Therefore, autolyzed yeast when provided at levels between 0.4% and 0.5% improved weaned piglets' performance.

Yeast cell wall polysaccharides enhanced expression of T helper type 1 and 2 cytokines profile in chicken B lymphocytes exposed to LPS challenge and enzyme treatment

1. The objective of this study was to investigate the potential immunomodulatory effects of yeast (Saccharomyces cerevisiae) and yeast-derived products treated with a cell wall lytic enzyme mixture on the gene expression of toll-like receptors and cytokines of chicken B cell line (DT 40) stimulated with lipopolysaccharide. 2. The effect of brewer's yeast (Y), yeast cell wall (YCW), distilled dried grains with solubles (DDGS) and a processed yeast + nucleotide-rich product (PY/N) treated with a yeast cell wall lytic enzyme (E) was assessed using a chicken B cells and LPS challenge model. 3. Relative gene expression of toll-like receptors (TLRs) and cytokines was investigated. Treatment of cells with Y, YCW, YCW + E and PY/N upregulated the expression of TLR2b following LPS challenge. Gene expression of TLR4 was downregulated in E, YCW and YCW + E treatments compared to control, while adding DDGS and PY/N upregulated the expression of TLR4 either before or after enzyme treatment. Following LPS challenge, expression of IL-4 and IL-10 was upregulated in cells treated with YCW and PY/N, both pre and post enzyme incubation. Adding YCW and PY/N to the cells challenged with LPS upregulated the expression of IFN-γ and IL-12 before and after enzyme treatment. Treatment of cells with YCW, DDGS and PY/N increased the expression of IL-6 prior to LPS challenge. 4. In conclusion, the results suggested that yeast-derived products affected immunomodulatory activities by changing the expression of cytokines involved in the innate immune response.

ASAS-NANP SYMPOSIUM: RUMINANT/NONRUMINANT FEED COMPOSITION: Challenges and opportunities associated with creating large feed composition tables

Traditional feed composition tables have been a useful tool in the field of animal nutrition throughout the last 70 yr. The objective of this paper is to discuss the challenges and opportunities associated with creating large feed ingredient composition tables. This manuscript will focus on three topics discussed during the National Animal Nutrition Program (NANP) Symposium in ruminant and nonruminant nutrition carried out at the American Society of Animal Science Annual Meeting in Austin, TX, on July 11, 2019, namely: 1) Using large datasets in feed composition tables and the importance of standard deviation in nutrient composition as well as different methods to obtain accurate standard deviation values, 2) Discussing the importance of fiber in animal nutrition and the evaluation of different methods to estimate fiber content of feeds, and 3) Description of novel feed sources, such as insects, algae, and single-cell protein, and challenges associated with the inclusion of such feeds in feed composition tables. Development of feed composition tables presents important challenges. For instance, large datasets provided by different sources tend to have errors and misclassifications. In addition, data are in different file formats, data structures, and feed classifications. Managing such large databases requires computers with high processing power and software that are also able to run automated procedures to consolidate files, to screen out outlying observations, and to detect misclassified records. Complex algorithms are necessary to identify misclassified samples and outliers aimed to obtain accurate nutrient composition values. Fiber is an important nutrient for both monogastrics and ruminants. Currently, there are several methods available to estimate the fiber content of feeds. However, many of them do not estimate fiber accurately. Total dietary fiber should be used as the standard method to estimate fiber concentrations in feeds. Finally, novel feed sources are a viable option to replace traditional feed sources from a nutritional perspective, but the large variation in nutrient composition among batches makes it difficult to provide reliable nutrient information to be tabulated. Further communication and cooperation among different stakeholders in the animal industry are required to produce reliable data on the nutrient composition to be published in feed composition tables.

Influence of dietary fermented Saccharomyces cerevisiae on growth performance, oxidative stress parameters, and immune response of cultured Oreochromis niloticus

Our trial was performed to investigate the effect of fully fermented yeast Sacharomyces cerevisiae (Hilyses, ICC Company, Brazil) on the growth performance and immune response of Oreochromis niloticus. In this study, a total of 270 O. niloticus (50.7 ± 0.8 g) were randomly divided into 3 groups in triplicates. The control group was fed on the basal diet while the other two groups were fed on a basal diet supplemented with 0.2% and 0.4% of Hilyses. The trial period extended for 2 months. At the end of the feeding trial, oxidant and antioxidant parameters (MDA, catalase, and glutathione reductase), some innate immunological parameters and immune-related gene expression were measured. Histological examination of liver, spleen, kidney, and intestine was performed. Further, fish groups were challenged against Gram-negative and Gram-positive bacteria; A. hydrophila and L. garvieae. The results revealed significant improvement (p < 0.05) in growth performance and feed utilization in Hilyses-treated groups versus the control group. Blood parameters and liver and kidney functions of Hilyses-supplemented groups were similar to those of the control group. The histological findings of treated groups showed normal tissue structure with multiple focal lymphoid aggregations in the spleen, kidney, and intestine. Both levels of Hilyses successfully enhanced phagocytic activity/index, lysozyme activity, and gene expression of TNF-α, and IL-1β. Fish group fed on 0.4% Hilyses exhibited the highest expression of IL-1β and the least mortality percentages post challenges. Thus, dietary supplementation of Hilyses could promote the growth performance and immunity and increase the resistance of O. niloticus against diseases.

Supplemental effects of dietary nucleotides on intestinal health and growth performance of newly weaned pigs

Intestinal challenges upon weaning would increase the needs of nucleotides for enterocyte proliferation, whereas de novo synthesis maybe insufficient. This study aimed to evaluate supplemental effects of dietary nucleotides on intestinal health and growth performance in newly weaned pigs. Fifty newly weaned pigs (19-d-old, 25 barrows and 25 gilts, 4.76 ± 0.42 kg BW) were individually housed and allotted to 5 treatments with increasing nucleotide supplementation (0, 50, 150, 250, and 500 mg/kg) based on a randomized complete block design with the initial BW and sex as blocks. Dietary nucleotides were provided from YT500 (Hinabiotech, Guangzhou, China). Pigs were fed for 21 d based on 2 phases (phase 1: 11 d and phase 2: 10 d) and experimental diets were formulated to meet or exceed nutrient requirements suggested by NRC (2012). Feed intake and BW were recorded. Titanium oxide (0.4%) was added as an indigestible marker from day 17. Plasma collected on day 18 was used to measure tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and malondialdehyde (MDA). Pigs were euthanized on day 21 to collect tissues to evaluate TNF-α, IL-6, MDA, morphology, and crypt cell proliferation rate in the jejunum. Ileal digesta were collected to measure ileal nutrient digestibility. Data were analyzed using contrasts in the MIXED procedure of SAS. Nucleotide supplementation increased (P < 0.05) ADFI in phase 1. Nucleotide supplementation at 50 and 150 mg/kg increased (P < 0.05) ADG in phase 1, whereas increased (P < 0.05) ADFI and tended to increase (P = 0.082) ADG in overall. Increasing nucleotide supplementation changed (quadratic, P < 0.05) villus height-crypt ratio (at 247 mg/kg) and decreased (linear, P < 0.05) crypt cell proliferation rate in the jejunum. Increasing nucleotide supplementation reduced (P < 0.05) jejunal IL-6 (at 50 and 150 mg/kg) and tended to change (quadratic, P = 0.074) plasma MDA (at 231 mg/kg). Nucleotide supplementation at 50 and 150 mg/kg increased (P < 0.05) ileal digestibility of energy and ether extract. In conclusion, nucleotide supplementation at a range of 50 to 250 mg/kg in the diets seems to be beneficial to newly weaned pigs by enhancing growth performance possibly due to reduced intestinal inflammation and oxidative stress as well as improved intestinal villi structure and energy digestibility.

Multi-strain yeast fraction product supplementation can alleviate weaning stress and improve performance and health of piglets raised under low sanitary conditions

BACKGROUND

This study was conducted to evaluate the health benefits to weaning pigs, raised under low sanitary conditions, of dietary supplementation with a multi-strain yeast fraction product (Cyberlindnera jadinii and Saccharomyces cerevisiae). In total, 160 weaning pigs (7.21 ± 1.05 kg) were randomly allotted to two dietary treatments in a 6-week feeding trial. The dietary treatments included a corn-soybean meal-based basal diet (CON) and CON + 2 g kg^-1 multi-strain yeast fraction product (MsYF) during weeks 1-2 and 0.4 g kg^-1 MsYF during weeks 3-6.

RESULTS

The MsYF supplementation increased (P < 0.05) body weight (BW) at day 42 and average daily gain (ADG) during days 1-14 and days 1-42 (P < 0.05) compared to CON. The total tract digestibility of dry matter (DM), fecal Lactobacillus counts, and serum immunoglobulin G (IgG) concentration at day 42 were higher (P < 0.05) in pigs fed a MsYF supplemented diet. The concentration of serum haptoglobin in pigs receiving a MsYF-supplemented diet was higher (P < 0.05) at days 7, 14, and 42 than those receiving CON. The mRNA expression for INF-γ and TNF-α genes were lower (P < 0.05) at days 14 and 7 respectively and the expression of IL-6 and TLR-2 genes was lower (P < 0.01) at days 7 and 14 in pigs fed an MsFY supplemented diet than those fed CON.

CONCLUSION

Supplementation with a multi-strain yeast fraction product had a positive effect on ADG during the early post-weaning period and led to better health in weaning pigs. © 2019 Society of Chemical Industry.

Effects of nucleotide supplementation on growth performance, nutrient digestibility, and immune blood profiles related to foot-and-mouth disease in vaccinated growing pigs

A 6 wk trial was conducted to evaluate the effects of nucleotide supplementation in improving performance, nutrient digestibility, and immune blood profiles so as to reduce foot-and-mouth disease (FMD) vaccine stress in growing pigs. A total of 120 growing pigs [(Yorkshire × Landrace) × Duroc] with an average body weight (BW) of 25.76 ± 1.83 kg were used. Pigs were allocated to one of three treatments (eight pens per treatment; three barrows and two gilts per pen) based on BW and sex. Pigs were injected with FMD vaccine at 84 d of age (2 wk after experiment started). Dietary treatments consisted of (1) CON: corn–soybean-meal-based diet, (2) NUC1: CON + 0.5% nucleotide, and (3) NUC2: CON + 1.0% nucleotide. In the current study, the growth performance of gain:feed ratio (G:F), the apparent total tract digestibility of dry matter and nitrogen was linearly (P < 0.05) increased with the increasing level of nucleotide. After injection, the concentration of cortisol and epinephrine was decreased (P < 0.05) linearly in nucleotide treatments. In conclusion, nucleotide supplementation to FMD vaccinated pigs showed positive effects on improving performance, immune system health, and reducing vaccine stress in growing pigs.

IRMS as a tool to obtain the carbon turnover (δ13 C) in organs of weaned piglets fed glutamic acid and nucleotides

Early weaning of piglets causes stress characterized by a decrease in feed intake followed by a decline in growth rates; thus, a fast recovery represents an essential step for proper growth of these animals. Considering that IRMS is a potential tool for non-destructive sampling and the fact that it provides time-integrated estimate of assimilated and not just ingested nutrients turned possible its application to evaluate the effects of dietary nucleotides and glutamate on carbon turnover (δ¹³ C) in organs of weanling piglets. At day 0, three piglets were slaughtered (prior to diet switch), the remaining eighty-four piglets weaned at 21-day-old were randomly assigned in a complete block design with a 2 × 2 factorial arrangement of treatments (two Nu levels: 0 and 0.1% and two Glu levels: 0 and 1%), being three piglets per treatment slaughtered on trial days 3, 6, 9, 14, 21, 35 and 49. The samples were analysed by IRMS and adjusted to first-order equation by a non-linear regression analysis using NLIN of SAS, in order to establish exponential graphics. After that, the turnover data were submitted to analysis of variance using GLM of SAS. The turnover value (t_95% ) verified for spleen was faster (p < 0.05) when glutamate was supplemented in diets. For pancreas and liver, the turnover rates were faster (p < 0.05) for the mixture of additives. However, for renal tissue, the turnover rate (t_95% ) was greater (p < 0.05) for the free additive diet. The results obtained suggest that the mixture of additives was more efficient to develop the digestive tract at post-weaning phase, taking into account the functional importance of pancreas and liver for nutrients' digestion and processing.

Effects of dietary yeast nucleotides supplementation on intestinal barrier function, intestinal microbiota, and humoral immunity in specific pathogen-free chickens

Yeast nucleotides are a fine functional additive in human and animals. The effects of dietary yeast nucleotides supplementation on intestinal development, expression of intestinal barrier-related genes, intestinal microbiota, and infectious bronchitis virus (IBV) antibody titer of specific pathogen-free (SPF) chickens were investigated. A total of 60 1-d-old chickens were divided into 4 groups, each of which included 3 replicates of 5 chickens. Group 1 served as a control that was fed a basal diet. Groups 2 to 4 were fed the basal diet supplemented with 0.1%, 0.3% and 0.5% yeast nucleotides, respectively. All chickens were inoculated intranasally with inactivated IBV vaccine at day 1 and day 10. At day 17, the intestinal development, expression of intestinal barrier-related genes and microbiota were evaluated. There was a significant increased ileal villus height and villus height to crypt depth ratio in group 2 (P < 0.05). Moreover, group 4 exhibited higher expression of zonula occludens-1 (ZO-1) and Occludin gene in ileum (P < 0.05), whereas groups 2 and 3 exhibited higher expression of Mucin 2 (MUC2) and trefoil factor 2 (TFF2) gene (P < 0.05), group 2 showed lower expression of IFN-α gene (P < 0.05). Dietary yeast nucleotides increased intestinal bacterial diversity (P < 0.05), and the abundance of Lactobacillus (P < 0.05). At day 10, 17, 24, 31, 38, and 45, the serum IBV antibody titers were tested. Group 2 exhibited higher IBV antibody titer at day 17 (P < 0.05), furthermore, groups 2 to 4 reached the effective levels 1 wk earlier than control group. In conclusion, dietary yeast nucleotides supplementation can help birds to mount a faster and stronger antibody response to IBV vaccine. In addition, dietary yeast nucleotides supplementation can also promote the intestinal development and barrier-related genes expression, and diversity and richness of intestinal microbiota.

Growth performance of nursery pigs fed diets containing increasing levels of a novel high-protein corn distillers dried grains with solubles

The objective of this study was to use the recently determined ME and standardized ileal digestibility (SID) values of AA for a novel high-protein distillers dried grains with solubles (HP-DDGS; PureStream 40, Lincolnway Energy LLC, Nevada, IA) to determine the optimal dietary inclusion rates in diets for nursery pigs. Three hundred and sixty pigs (BW = 6.79 ± 0.02 kg) were blocked by BW, and pens within blocks were assigned randomly to one of four dietary treatments (10 pens/treatment, 9 pigs/pen). Dietary treatments consisted of adding 0%, 10%, 20%, or 30% HP-DDGS to nursery diets during phase 2 (days 7-21) and phase 3 (days 21-42) of a three-phase nursery feeding program. Diets within each phase were formulated to contain equivalent amounts of ME, SID Lys, Met, Thr, and Trp, Ca, standardized total tract digestible P, vitamins, and trace minerals. Calculated SID Leu to Lys ratios for 0%, 10%, 20%, and 30% HP-DDGS diets were 119%, 137%, 156%, and 173% in phase 2 diets and 120%, 131%, 143%, and 160% in phase 3 diets. The SID Ile to Lys ratios ranged from 60% to 69% in phase 2 diets and from 54% to 59% in phase 3 diets. The SID Val to Lys ratios ranged from 63% to 79% in phase 2 diets and 64% to 68% in phase 3 diets. Body weight and feed disappearance were measured weekly. During phase 2, ADG, ADFI, and G:F were reduced linearly (P < 0.01) as the diet inclusion rate of HP-DDGS increased. Similarly in phase 3, increasing dietary levels of HP-DDGS depressed ADG, ADFI, and G:F linearly (P < 0.01). Overall growth performance of phases 2 and 3 of nursery pigs was negatively affected by increasing levels of HP-DDGS in these diets. Pigs acquired a Streptococcus suis and Escherichia coli disease challenge during the experiment. Although no differences in morbidity were observed throughout the experiment, including HP-DDGS in diets tended to decrease (P = 0.08) mortality. In conclusion, a linear decrease in nursery pig growth performance was observed as increasing levels of HP-DDGS were added in diets, which was probably due to overestimation of SID AA content of the HP-DDGS, antagonistic effects of excess Leu, and the effects of relatively high fiber content.

Timing carbon turnover (δ13C) in weaned piglet's brain by IRMS

Isotope-ratio mass spectrometry (IRMS) is a potential tool that provides time-integrated estimate of assimilated and not just ingested nutrients. This feature turned possible its application to evaluate the effects of dietary nucleotides and glutamate on carbon turnover (δ13C) in the brain of weanling piglets. Eighty-seven piglets weaned at 21-day-old were used, being three piglets slaughtered at day-0 (prior to diet-switch) and, the remaining 84 randomly assigned in a complete block design with a 2 x 2 factorial arrangement of treatments (two nucleotide levels: 0% and 0.1% and, two glutamate levels: 0% and 1%). On trial days 3, 6, 9, 14, 21, 35 and 49, three piglets per treatment were also slaughtered. The samples were analyzed by IRMS and adjusted to the first-order equation by a nonlinear regression analysis using NLIN procedure of SAS, in order to obtain the exponential graphics. The carbon turnover (t95%) verified for cerebral tissue was faster (P<0.05) for diet containing glutamate in comparison to other diets, supporting the fact that glutamate contributed to develop the piglets' brain, due to the fastest incorporation of 13C-atoms in this tissue at post-weaning phase, despite the energy deficit experienced by them.

Intestinal Nucleoside Transporters: Function, Expression, and Regulation

The gastrointestinal tract is the absorptive organ for nutrients found in foods after digestion. Nucleosides and, to a lesser extent nucleobases, are the late products of nucleoprotein digestion. These metabolites are absorbed by nucleoside (and nucleobase) transporter (NT) proteins. NTs are differentially distributed along the gastrointestinal tract showing also polarized expression in epithelial cells. Concentrative nucleoside transporters (CNTs) are mainly located at the apical side of enterocytes, whereas equilibrative nucleoside transporters (ENTs) facilitate the basolateral efflux of nucleosides and nucleobases to the bloodstream. Moreover, selected nucleotides and the bioactive nucleoside adenosine act directly on intestinal cells modulating purinergic signaling. NT-polarized insertion is tightly regulated. However, not much is known about the modulation of intestinal NT function in humans, probably due to the lack of appropriate cell models retaining CNT functional expression. Thus, the possibility of nutritional regulation of intestinal NTs has been addressed using animal models. Besides the nutrition-related role of NT proteins, orally administered drugs also need to cross the intestinal barrier, this event being a major determinant of drug bioavailability. In this regard, NT proteins might also play a role in pharmacology, thereby allowing the absorption of nucleoside- and nucleobase-derived drugs. The relative broad selectivity of these membrane transporters also suggests clinically relevant drug-drug interactions when using combined therapies. This review focuses on all these physiological and pharmacological aspects of NT protein biology. © 2017 American Physiological Society. Compr Physiol 8:1003-1017, 2018.