Dietary replacement of inorganic trace minerals with lower levels of organic trace minerals leads to enhanced antioxidant capacity, nutrient digestibility, and reduced fecal mineral excretion in growing-finishing pigs.

Introduction: More effective and environment-friendly organic trace minerals have great potential to replace the inorganic elements in the diets of livestock. This study aimed to investigate the effects of dietary replacement of 100% inorganic trace minerals (ITMs) with 30-60% organic trace minerals (OTMs) on the performance, meat quality, antioxidant capacity, nutrient digestibility, and fecal mineral excretion and to assess whether low-dose OTMs could replace whole ITMs in growing-finishing pigs' diets. Methods: A total of 72 growing-finishing pigs (Duroc × Landrace × Yorkshire) with an initial average body weight of 74.25 ± 0.41 kg were selected and divided into four groups with six replicates per group and three pigs per replicate. The pigs were fed either a corn-soybean meal basal diet containing commercial levels of 100% ITMs or a basal diet with 30, 45, or 60% amino acid-chelated trace minerals instead of 100% ITMs, respectively. The trial ended when the pigs' weight reached ~110 kg. Results: The results showed that replacing 100% ITMs with 30-60% OTMs had no adverse effect on average daily gain, average daily feed intake, feed/gain, carcass traits, or meat quality (P > 0.05) but significantly increased serum transferrin and calcium contents (P < 0.05). Meanwhile, replacing 100% ITMs with OTMs tended to increase serum T-SOD activity (0.05 ≤ P < 0.1), and 30% OTMs significantly increased muscle Mn-SOD activity (P < 0.05). Moreover, replacing 100% ITMs with OTMs tended to increase the apparent digestibility of energy, dry matter, and crude protein (0.05 ≤ P < 0.1) while significantly reducing the contents of copper, zinc, and manganese in feces (P < 0.05). Discussion: In conclusion, dietary supplementation with 30-60% OTMs has the potential to replace 100% ITMs for improving antioxidant capacity and nutrient digestibility and for reducing fecal mineral excretion without compromising the performance of growing-finishing pigs.

Effects of zinc oxide and condensed tannins on the growth performance and intestinal health of weaned piglets in ETEC-challenged environment.

This experiment was conducted to evaluate effects of zine oxide (ZnO) and condensed tannins (CT), independently or in combination, on the growth performance and intestinal health of weaned piglets in enterotoxigenic Escherichia coli (ETEC-K88)-challenged environment. Randomly divided 72 weaned piglets into 4 groups. Dietary treatments included the following: basic diet group (CON), 1,500 mg/kg zinc oxide group (ZnO), 1,000 mg/kg condensed tannins group (CT), and 1,500 mg/kg zinc oxide +1,000 mg/kg condensed tannins group (ZnO + CT). Dietary ZnO supplementation decreased diarrhea rate from 0 to 14 days, 15 to 28 days, and 0 to 28 days (p < 0.05) and no significant on growth performance. The effect of CT on reducing diarrhea rate and diarrhea index was similar to the results of ZnO. Compared with the CON group, ZnO increased the ileum villus height and improved intestinal barrier function by increasing the content of mucin 2 (MUC-2) in jejunum and ileum mucosa and the mRNA expression of zonula occludens-1 (ZO-1) in jejunum (p < 0.05) and the expression of Occludin in duodenum and ileum (p < 0.05). The effects of CT on intestinal barrier function genes were similar to that of ZnO. Moreover, the mRNA expression of cystic fibrosis transmembrane conductance regulator (CFTR) in jejunum and ileum was reduced in ZnO group (p < 0.05). And CT was also capable of alleviating diarrhea by decreasing CFTR expression and promote water reabsorption by increasing AQP3 expression (p < 0.05). In addition, pigs receiving ZnO diet had higher abundance of phylum Bacteroidetes, and genera Prevotella, and lower phylum Firmicutes and genera Lactobacillus in colonic contents. These results indicated that ZnO and CT can alleviate diarrhea and improve intestinal barrier function of weaned pigs in ETEC-challenged environment. In addition, the application of ZnO combined with CT did not show synergistic effects on piglet intestinal health and overall performance. This study provides a theoretical basis for the application of ZnO in weaning piglet production practices, we also explored effects of CT on the growth performance and intestinal health of weaned piglets in ETEC-challenged environment.

Dietary Stevia Residue Extract Supplementation Improves Antioxidant Capacity and Intestinal Microbial Composition of Weaned Piglets.

This study aimed to investigate the effects of diet supplementation with stevia residue extract (SRE) on growth performance, intestinal health, and antioxidant capacity of weaned piglets. A total of 144 weaned piglets (body weight 6.8 ± 0.5 kg) were randomly selected and allocated into four treatment groups with six replicates of six pigs/pen. The treatments consisted of a basal diet without SRE or basal diet supplemented with 100, 200, or 400 mg/kg SRE. The results showed that the addition of 200 mg/kg SRE to the diet significantly reduced (p < 0.05) the diarrhea rate of piglets compared with the control group. The supplementation of 400 mg/kg SRE in the diet significantly reduced the piglets' serum MDA content and significantly increased (p < 0.05) the T-AOC, T-SOD, and GSH-PX activity in the serum. The dietary supplementation with 400 mg/kg SRE significantly increased (p < 0.05) the CAT and GSH-PX activity in the liver. Moreover, the supplementation of 400 mg/kg SRE in the diet significantly increased (p < 0.05) the relative abundance of Prevotellaceae (genus) and Roseburia (genus) beneficial bacteria compared to the control group. Spearman's correlation analysis showed that Prevotella (genus) abundance was positively correlated with liver GSH-PX activity and acetic acid content of colon contents. In conclusion, the supplementation of 400 mg/kg SRE to the diet can improve piglet health by regulating antioxidant reduction homeostasis, which may also be associated with an increase in the relative numbers of potentially beneficial bacteria.

Depression and anxiety of medical students at Kunming Medical University during COVID-19: A cross-sectional survey.

An isolation strategy was used to control the transmission and rapid spread of COVID-19 in Yunnan. As a result, students were supposed to stay at home and disrupted their outside activities. It led to a detrimental influence on students' mental health. The purpose of this study was to investigate the prevalence and risk factors of depression and anxiety among medical students and to provide ideas for the prevention of depression and anxiety in medical students. A cross-sectional survey was conducted among 2,116 medical students at Kunming Medical University from July 8 to July 16, 2020. Participants' demographic and living conditions were collected. Depression and anxiety were measured using the Patient Health Questionnaire 9 and General Anxiety Disorder-7, respectively. Uni- and multivariate logistic regression analyses were performed to detect risk factors associated with depression and anxiety. The prevalence rates of depression and anxiety among medical students were 52.5 and 29.6%, respectively. Depression was more likely to be caused by low grades, lack of physical exercise, drug use, irregular diet, extensive screen time on mobile phones, being greatly affected by the COVID-19 pandemic, and inadaptability to offline courses. Anxiety was more likely to be caused by lack of physical exercise, drug use, irregular diet, and inadaptability to offline courses. Depression and anxiety are highly comorbid. Our study showed predictive factors for depression and anxiety and identified a major mental health burden on medical students during the COVID-19 outbreak. More targeted measures should be taken to improve the mental state of students to reduce the incidence of depression and anxiety.

Effects of niacin on intestinal epithelial Barrier, intestinal Immunity, and microbial community in weaned piglets challenged by PDCoV.

The objective was to evaluate effects of niacin on the intestinal epithelial barrier, intestinal immunity, and microbial community in weaned piglets challenged by Porcine Deltacoronavirus (PDCoV). In this study, fifteen weaned piglets were randomly assigned to 1 of 3 groups, (1) control group, normal diet; (2) PDCoV group, infected with 1 × 107 TCID50 of the PDCoV CHN-HN-17 strain by oral administration; (3) NA + PDCoV group, infected with 1 × 107 TCID50 of the PDCoV CHN-HN-17 strain by oral administration following administration of 40 mg of niacin for three days. The results showed that PDCoV infection induced diarrhea and other clinical symptoms with intestinal villi shedding and atrophy in weaned piglets. Niacin alleviated the symptoms of diarrhea and intestinal damage of PDCoV-infected weaned piglets. Additionally, PDCoV increased (P < 0.05) the mRNA expression of tight junction proteins [zonula occludens-1 (ZO-1) and Claudin] and antimicrobial peptides [porcine ß defensin 1 (pBD1), pBD2, proline-arginine rich 39-amino acid peptide (PR39) and protegrin 1-5 (PG1-5) in the jejunum and ileum of weaned piglets, while niacin increased (P < 0.05) the expression of PG1-5 compared with PDCoV. PDCoV increased (P < 0.05) the contents of serum interleukin-1ß (IL-1ß), IL-8 and intestinal IL-8, and up-regulated the mRNA expression of tumor necrosis factor-α (TNF-α), IL-1ß, IL-6, IL-10, IL-12, and IL-18 in ileum of weaned piglets compared with control. However, niacin decreased (P < 0.05) the contents of serum IL-1ß, IL-6 and intestinal IL-10 and IL-8, and also reduced (P < 0.05) the mRNA expression of ileal TNF-α, IL-10 and IL-12 in the PDCoV-infected piglets. Compared with control, PDCoV up-regulated (P < 0.05) the mRNA expression of key genes related to innate immune and antiviral molecules [toll-like receptor 4 (TLR4), NOD1, NOD2, DDX58, CCL2, STAT2, Mx1, IFN-γ, and protein kinase R (PKR) in the ileum of weaned piglets. Niacin decreased (P < 0.05) the mRNA expression of NOD1, NOD2, STAT2, IFN-γ, and PKR in PDCoV-infected weaned piglets. Moreover, the mRNA expression of IL-6 decreased (P < 0.05) and 2'-5'-oligoadenylate synthetase (OAS), IFN-α, and PKR increased (P < 0.05) in PDCoV-infected IPEC-J2 cells treated with niacin in vitro. Furthermore, niacin decreased (P < 0.05) the elevation of protein expression including inducible NOS (iNOS), nuclear factor-κB (NF-κB p65), inhibitor kappa B (IKKß), histone deacetylase [Sirtuin 1 (SIRT1) and histone deacetylase 7 (HDAC7) and phosphorylation of histone H3 at serine s10 (pH3s10) in the ileum of PDCoV-infected piglets, and increased (P < 0.05) the expression of G protein-coupled receptor (GPR109A). PDCoV disrupted the composition and structure of microflora in the colon of weaned piglets, and reduced the relative abundance of the beneficial bacteria Spirobacterium, but niacin could improve the intestinal microbial flora of the PDCoV-infected piglets associated with increasing the relative abundance of Lactobacillus. Overall, niacin could alleviate diarrhea, intestinal barrier damages, intestinal immune response and colonic microflora disfunction in PDCoV-infected weaned piglets.

The Responses of Lactobacillus reuteri LR1 or Antibiotic on Intestinal Barrier Function and Microbiota in the Cecum of Pigs.

This study aimed to investigate responses of the Lactobacillus reuteri or an antibiotic on cecal microbiota and intestinal barrier function in different stages of pigs. A total of 144 weaned pigs (Duroc × Landrace × Yorkshire, 21 days of age) were randomly assigned to the control group (CON, fed with a basal diet), the antibiotic group (AO, fed with basal diet plus 100 mg/kg olaquindox and 75 mg/kg aureomycin), and the L. reuteri group (LR, fed with the basal diet + 5 × 1010 CFU/kg L. reuteri LR1) throughout the 164-d experiment. A total of 45 cecal content samples (5 samples per group) from different periods (14th, 42th, and 164th days) were collected for 16S rRNA gene amplification. The results revealed that although LR and AO did not change the diversity of cecal microbiota in pigs, the abundance of some bacteria at the genus level was changed with age. The proportion of Lactobacillus was increased by LR in early life, whereas it was decreased by AO compared with the control group. The relative abundance of Ruminococcaceae was increased along with age. In addition, the gas chromatography results showed that age, not AO or LR, has significant effects on the concentrations of SCFAs in the cecum of pigs (P < 0.05). However, the mRNA expression of tight junction proteins zonula occluden-1 (ZO-1) and occludin were increased by AO in the cecum of pigs on day 14, while LR increased the mRNA expression of intestinal barrier-related proteins ZO-1, occludin, mucin-1, mucin-2, PG1-5, and pBD2 in the cecum of pigs on days 14 and 164 (P < 0.05). In conclusion, LR and AO have different effects on the intestinal barrier function of the cecum, and neither LR nor AO damaged the intestinal barrier function of pig cecum. In addition, LR and AO have little effects on cecal microflora in different stages of the pigs. The microflora and their metabolite SCFAs were significantly changed along with age. These findings provide important information to understand the homeostasis of the cecum of pigs after antibiotic or probiotic treatment.

Neuroprotection of Oral Edaravone on Middle Cerebral Artery Occlusion in Rats.

Edaravone has been widely used in the treatment of acute ischemic stroke. However, there has been no oral preparation of edaravone in the clinic. In this study, we assessed the effect and possible mechanisms of oral edaravone on the middle cerebral artery occlusion (MCAO) model in rats. Highly bioavailable form of novel edaravone formulation developed using self-nanomicellizing solid dispersion strategy which showed up to 16.1-fold improved oral bioavailability was considered oral edaravone. The male rats (n = 84) were randomly divided into sham; model; oral edaravone in low dose (10 mg/kg), medium dose (20 mg/kg), and high dose (30 mg/kg); and edaravone by intraperitoneal administration group (IP group, 10 mg/kg). Rats were treated with different drugs 5 h after the operation, twice a day for 7 days. The behavioral data were dose-dependently improved by oral edaravone and sensorimotor functions of the high dose group were similar to those of the edaravone by IP route group. Furthermore, oral edaravone significantly reduced cerebral infarction area and downregulated the levels of caspase-3, GFAP, Iba1, 3-NT, and 4-HNE, whereas upregulated those of Vamp-2 and Map-2 in a dose-dependent manner. Especially effect of the high dose on these molecules was equal to that of edaravone by IP administration. Taken together, our data suggest that the improvement of sensorimotor deficits by oral edaravone in high doses after ischemia is similar to that in edaravone by IP administration. Neuroprotection of oral edaravone is at least partial by minimizing oxidative stress, the overactivation of glial cells, and the levels of the apoptosis-associated proteins, and alleviating synaptic damage in a dose-dependent manner.

Effects of Niacin on Resistance to Enterotoxigenic Escherichia coli Infection in Weaned Piglets.

Nicotinic acid (NA) has been used to treat different inflammatory disease with positive influence, the mechanisms by which NA exerts its anti-inflammatory effects remain largely undefined. Here we proposed a new hypothesis that NA manipulated endogenous antimicrobial peptides (AMPs) which contributed to the elimination of enterotoxigenic Escherichia coli (ETEC) K88, and thus affects the alleviation of inflammation. Therefore, an experiment in weaned piglets treated with 40 mg NA for 3 days before ETEC K88 challenge was designed to investigate the effects of NA on resistance to enterotoxigenic E. coli infection in weaned piglets. Twenty-four weaned piglets were randomly assigned to 1 of 4 treatments based on weight and sex. The control and NA treated groups were administered 20 mL normal saline or 20 mL NA solution. The K88 challenged and NA treated plus K88 challenged groups were administered 20 mL normal saline or 20 mL nicotinic acid solution once daily for 3 consecutive days. On the fourth day, the K88 and K88 + NA groups were treated with oral administration of 4 × 109 cfu/mL ETEC K88. The results showed that NA alleviated the clinical symptoms of weaned piglets infected with ETEC K88. NA significantly reduced the amount of ETEC K88 in the spleen and liver (P < 0.05). The intestinal morphological damage caused by ETEC K88 infection was alleviated by NA in weaned piglets. In addition, NA significantly alleviated the expression of inflammatory cytokine [Interleukin-6 (IL-6), Interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α)] in the serum and intestines of weaned piglets infected with ETEC K88 (P < 0.05). NA significantly increased the content of secretory IgA (SIgA) and the expression of antimicrobial peptides [porcine ß defensin-2 (pBD2), protegrin1-5 (PG1-5) and PR39] in intestines of weaned pigs. NA increased the diversity of microflora in colonic contents, while NA significantly reduced the relative abundance of Bacteroidetes, Bacteroidales, and Bacteroidia in weaned piglets infected with ETEC K88 (P < 0.05). Furthermore, the NA group significantly reduced the level of HDAC7 in jejunum (P < 0.05) and increased the level of SIRT1 in the colon compared with the Control group. Moreover, NA significantly increased the levels phosphorylation of histone H3 at Ser10 (pH3S10) in ileum and the levels of acetylation of lysine 9 on histone 3 (acH3K9) and acH3K27 in colon (P < 0.05) in weaned piglets infected with ETEC K88 (P < 0.05). In conclusion, NA can alleviate the clinical symptoms, the damage of intestinal morphology, and intestinal inflammation in weaned piglets infected ETEC K88 through enhancing the expression of endogenous AMPs by associating the histone acetylation modification.

Effects of Fermented Feed on the Growth Performance, Intestinal Function, and Microbiota of Piglets Weaned at Different Age.

The beneficial function of fermented feed in livestock industry has been widely investigated. However, little is known about the effects of fermented feed on different weaned-day piglets. This study aimed to investigate the effects of fermented diet on the growth performance, intestinal function, and microbiota of piglets weaned at the age of 21 and 28 days. The results found that weaning on day 21 significantly increased (p < 0.05) average daily gain (ADG), and average daily feed intake (ADFI) (calculated based on wet weight and dry matter), while reduced (p < 0.05) feed to gain ratio (F:G), the activities of trypsin and lipase of jejunum and the villus height of ileum, compared with 28-days weaning. The protein levels of Occludin, Claudin-1, and ZO-1 of ileum in the groups weaning on day 21 were less (p < 0.05) than the groups weaning on day 28. Moreover, dietary supplementation with fermented diet upregulated (p < 0.05) the Occludin, Claudin-1, and ZO-1 proteins of ileum, compared with the groups treated with control diet both weaning on day 21 and 28. In addition, dietary supplementation with fermented diet decreased (p < 0.05) the relative abundance of Clostridia (class) and increased (p < 0.05) the Bacteroidia (class) level of cecal microbiota, compared with the groups treated with control diet both weaning on day 21 and 28. However, supplementation with fermented diet did not affect the concentrations of short-chain fatty acids in the cecum (p > 0.05). Therefore, our data suggest that the feed digestibility is improved in piglets weaned at 21 days, but intestinal barrier function is weaker than in piglets weaned at 28 days. However, compared with feeding control diet, supplementation with fermented diet both improved the feed conversion and intestinal barrier function of weaned piglets by modulating intestinal microbiota.

Effects of early sub-therapeutic antibiotic administration on body tissue deposition, gut microbiota and metabolite profiles of weaned piglets.

BACKGROUND: This study aimed to evaluate the effects of sub-therapeutic antibiotic (STA) administration and its subsequent withdrawal on the body tissue deposition, gut microbiota, and metabolite profiles of piglets. The piglets in the experimental group were fed with STA (30 mg kg-1 bacitracin methylene disalicylate, 75 mg kg-1 chlortetracycline, 300 mg kg-1 calcium oxytetracycline) for 14 days and the target bodyweight of the withdrawal period was 25 kg. RESULTS: The experiment was divided into two periods: the administration period and the withdrawal period. The results showed that STA did not improve piglets' growth performance during the two periods. Piglets treated with STA had lower body water deposition during the withdrawal period and tended to increase body lipid deposition during the withdrawal period and the whole period in comparison with the piglets in the control group. It was found that STA markedly altered the colonic microbiota and their metabolites in the piglets. Sub-therapeutic antibiotics were initially effective in decreasing the abundance of pathogenic bacteria during the administration period; however, STA could not continue the effect during the withdrawal period, leading to a rebound of pathogenic bacteria such as Alloprevotella and the increased abundance of other pathogenic bacteria like Oscillibacter. Remarkably, STA treatment decreased Blautia abundance. This bacterium plays a potential protective role against obesity. Metabolomic analysis indicated that STA mainly altered amino acid metabolism, lipid metabolism, and carbohydrate metabolism during the two periods. Spearman's correlation analysis showed that the gut microbiota was highly correlated with microbial metabolite changes. CONCLUSION: These results suggest that early STA administration may alter body tissue deposition later in life by reshaping the gut microbiota and their metabolite profiles. © 2022 Society of Chemical Industry.

Dietary stevia residue extract supplementation improves the performance and antioxidative capacity of growing-finishing pigs.

BACKGROUND: Improper disposal of stevia residue causes environmental pollution and waste of resources. The extract of stevia residue is rich in chlorogenic acid and isochlorogenic acids, and has a great potential in livestock and poultry breeding. Therefore, this study aimed to investigate the effects of dietary stevia residue extract (SRE) supplementation on the performance, meat quality, antioxidative capacity and gut microbiota in growing-finishing pigs. RESULTS: The results showed that increasing the concentration of SRE supplementation linearly increased (P < 0.05) body weight from day 1 to 35. Supplementation with SRE significantly increased (P < 0.05) average daily gain (ADG) from day 1 to 75. 100 mg kg-1 SRE supplementation significantly increased (P < 0.05) hot carcass weight and gastric index. Moreover, increasing the concentration of SRE linearly increased (P < 0.05) the score of appearance of longissimus thoracis, as well as serum albumin, triglyceride and high-density lipoprotein cholesterol content. Further study found that increasing the concentration of SRE linearly increased (P < 0.05) serum total superoxide dismutase activity, and showed a significant quadratic relationship (P < 0.05) with activity of serum catalase, while linearly decreasing (P < 0.05) muscle malondialdehyde (MDA) content. Furthermore, supplementation with 100 mg kg-1 SRE significantly decreased (P < 0.05) serum MDA content, while 600 and 800 mg kg-1 SRE supplementation significantly decreased (P < 0.05) muscle MDA content. However, SRE supplementation had no significant effect on gut microbiota (P > 0.05). CONCLUSION: These data indicated that dietary SRE supplementation improves the performance and antioxidative capacity of growing-finishing pigs. We recommend that the optimal supplemental level of SRE in the diet of growing-finishing pigs is 100 mg kg-1 . © 2022 Society of Chemical Industry.

Alterations in intestinal microbiota composition coincide with impaired intestinal morphology and dysfunctional ileal immune response in growing-finishing pigs under constant chronic heat stress.

BACKGROUND: Previous studies had shown that short-term acute heat stress (HS) affected the host's metabolism and intestinal microbiota independent of feed intake (FI) reduction, and long-term calorie restriction caused intestinal morphological injuries and gut microbial alterations. However, research on the effects of constant chronic HS on intestinal microbial composition and the roles of FI reduction played in is limited. This study aimed to investigate the effects of 7-day constant chronic HS on the composition of intestinal microbes in growing-finishing pigs, and its relationship with pigs' performance, intestinal morphology, and ileal immune response. Twenty-four growing-finishing pigs (Duroc × Large White × Landrace, 30 ± 1 kg body weight) were randomly assigned to three treatments (n = 8), 1) thermal neutral (TN) conditions (25 ± 1 °C) with ad libitum FI, 2) HS conditions (35 ± 1 °C) with ad libitum FI, 3) pair-fed (PF) with HS under TN conditions to discriminate the confounding effects of dissimilar FI, and the FI was the previous day's average FI of HS. The small intestinal segments (duodenum, jejunum, and ileum) and feces were collected on d 8. RESULTS: Results indicated that HS drastically declined (P < 0.05) average daily gain (ADG) and average daily feed intake (ADFI) (about 61%) in comparison with TN, and caused hyperpyrexia, meanwhile PF caused hypothermia. Morphological observation by light and electron microscopes showed that both HS and PF treatment decreased (P < 0.05) the villus and microvillus height compared with TN. Additionally, HS increased (P < 0.05) protein expression of heat shock protein 70 in the duodenum, jejunum, and ileum. Furthermore, the expression of tight junction protein zonula occluden-1 (ZO-1) in the duodenum and ileum, and Occludin in the ileum were enhanced (P < 0.05) compared with TN and PF. Moreover, HS significantly enhanced (P < 0.05) the mRNA relative expression of inflammatory cytokines (TLR-2, TLR-4, and tumor necrosis factor-α (TNF-α), IL-6, IL-8, PG1-5, ß-defensin 2 (pBD-2)), mucins (mucin-1 and mucin-2) and P65 protein level in the ileal mucosa tissue. Intestinal microbiota analysis by 16S rRNA sequencing showed lower (P < 0.10) α diversity in both HS and PF, and a separated cluster of ß diversity among groups. Compared with TN, HS but not PF mainly reduced (FDR < 0.05) Bacteroidetes (phylum), Bacteroidia (class) and elevated the proportions of Proteobacteria (phylum, FDR < 0.05), Bacillales (order, FDR < 0.05), Planococcaceae (family, FDR < 0.05), Kurthia (genus, FDR < 0.05), Streptococcaceae (family, FDR < 0.10) and Streptococcus (genus, FDR < 0.10). Notably, Lactobacillales (order) was decreased (FDR < 0.05) by PF alone. Furthermore, the Spearman correlation analysis indicated that the microbes prevalent in HS were positively (P < 0.05) associated with intestinal morphological injuries indicators and ileal immune response parameters, and the microbes reduced in HS were negatively (P < 0.05) with the performance data. CONCLUSIONS: Intestinal morphological injuries and ileal immune response caused by constant chronic HS independent of FI showed close connections with alterations in intestinal microbiota in growing-finishing pigs.

Comparative Effects of L. plantarum CGMCC 1258 and L. reuteri LR1 on Growth Performance, Antioxidant Function, and Intestinal Immunity in Weaned Pigs.

Lactobacillus plantarum CGMCC 1258 and Lactobacillus reuteri LR1 are two important strains of probiotics. However, their different advantages in the probiotic effect of weaned pigs are still poorly understood. Therefore, the study was to investigate the comparative effects of dietary supplementation of L. plantarum CGMCC 1258 and L. reuteri LR1 on growth performance, antioxidant function, and intestinal immunity in weaned pigs. Ninety barrows [initial body weight (BW) = 6.10 ± 0.1 kg] 21 days old were randomly divided into 3 treatments with 5 replicates, each replicate containing 6 pigs. Pigs in control (CON) were fed a basal diet, and the basal diets supplemented with 5 × 1010 CFU/kg L. plantarum CGMCC 1258 (LP) or L. reuteri LR1 (LR) for 42 days, respectively. The results showed that LP increased (p < 0.05) serum superoxide dismutase (SOD), and decreased (p < 0.05) serum malondialdehyde (MDA) and the expression and secretion of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) in intestinal mucosa, but has no significant effect on growth performance and diarrheal incidence. However, LR increased (p < 0.05) final BW and average daily gain (ADG), reduced (p < 0.05) 29-42-day diarrheal incidence, decreased (p < 0.05) the expression and secretion of IL-1ß, IL-6, TNF-α, and IFN-γ, and increased (p < 0.05) the expression of transforming growth factor-ß (TGF-ß) in intestinal mucosa. In addition, the serum glutathione peroxidase (GSH-PX), mRNA relative expression of Na+-K+-2Cl- co-transporter 1 (NKCC1) and cystic fibrosis transmembrane conductance regulator (CFTR) and the content of toll-like relative (TLR2) and TLR4 in the jejunum, and secretory immunoglobulin (sIgA) content of ileal mucosa were higher (p < 0.05) than LP. Collectively, dietary L. plantarum CGMCC 1258 improved intestinal morphology, intestinal permeability, intestinal immunity, and antioxidant function in weaned pigs. Dietary L. reuteri LR1 showed better growth performance, a lower incidence of diarrhea, better intestinal morphology, and a higher extent of immune activation in weaned pigs.

Effects of Protein Restriction and Subsequent Realimentation on Body Composition, Gut Microbiota and Metabolite Profiles in Weaned Piglets.

The objective of this study was to evaluate the effects of protein restriction and subsequent protein realimentation on the body composition, gut microbiota and metabolite profiles of piglets. Fifty weaned piglets were randomly assigned to two treatments: a normal protein (NP) group (20% crude protein (CP)) or a low protein (LP) group (16% CP) with five animals per pen and five pens per group. Treatment diets were fed for 14 d during the protein restriction phase, and then all pigs were fed the same nursery diets with a normal CP level (19% CP) during the protein realimentation phase until they reached an average target body weight (BW) of 25 ± 0.15 kg. At day 14 and the end of the experiment, one piglet close to the average BW of each pen was slaughtered to determine body composition, microbial composition and microbial metabolites. Results showed that there was no difference (p > 0.05) in the experimental days to reach target BW between the LP and NP groups. The average daily gain (ADG) and gain:feed ratio (G:F) during the protein restriction phase as well as BW at day 14, were significantly decreased (p < 0.05) in the LP group compared with the NP group. However, there were no significant differences (p > 0.05) during the protein realimentation phase and the overall experiment. Similarly, piglets in the LP group showed a significantly decreased body protein content (p < 0.05) at day 14, but not (p > 0.05) at the end of the experiment. The relative abundance of Parabacteroides, Butyricicoccus, Olsenella, Succinivibrio and Pseudoramibacter were significantly increased (p < 0.05), while the relative abundance of Alloprevotella and Faecalicoccus were significantly decreased (p < 0.05) in the LP group at day 14. At the end of the experiment, the piglets in the LP group showed a higher (p < 0.05) colonic relative abundances of Parabacteroides, unidentified Christensenellaceae and Caproiciproducens, and a lower (p < 0.05) relative abundance of unidentified Prevotellaceae, Haemophilus, Marvinbryantia, Faecalibaculum, Neisseria and Dubosiella than those in the NP group. Metabolomics analyses indicated that tryptophan metabolism and vitamin metabolism were enriched in the LP group at day 14, and glycerophospholipid metabolism and fatty acid esters of hydroxy fatty acid metabolism were enriched at the end of the experiment. Moreover, Spearman's correlation analysis demonstrated that the microbial composition was highly correlated with changes in colonic metabolites. Collectively, these results indicated that protein restriction and subsequent realimentation lead to compensatory growth and compensatory protein deposition in piglets and contribute to animal intestinal health by altering the gut microbiota and its metabolites.

Effects of niacin on intestinal immunity, microbial community and intestinal barrier in weaned piglets during starvation.

The objective was to evaluate the effects of niacin on intestinal immunity, microbial community and intestinal barrier in weaned piglets during starvation. In this study, twelve weaned piglets with similar body weight were randomly divided into two groups, six for each group. These piglets were treated with starvation, one group was treated with10 ml normal saline (Control), and the other group was perfused with 10 ml niacin solution (Niacin, 40 mg niacin was dissolved in equal volume of normal saline) once daily for three consecutive days. The results showed that niacin effectively attenuated the weight loss and diarrhea index (P < 0.05) in weaned piglets; Niacin improved jejunal villous height and intestinal morphological score (P < 0.05); Additionally, niacin significantly increased the mRNA expression of antimicrobial peptide (pBD2 and PR39) in the jejunum (P < 0.05); Meanwhile, niacin significantly increased ZO-1 and Occludin expression in the jejunum (P < 0.05). Furthermore, niacin improved the microbiota and the concentrations of acetate (P < 0.05). Conversely, niacin decreased the ratios of propionate/acetate and butyrate/acetate in the colonic contents of weaned piglets (P < 0.05); Interestingly, niacin increased the protein expression of SIRT1 (P < 0.05) and inhibited the protein expression of HDAC7 (P < 0.05). In conclusion, niacin attenuated the weight loss and diarrhea, and improved the expression of antimicrobial peptides, and enhanced intestinal epithelial barrier function, and improved the microbiota in the colonic contents of weaned piglets, suggesting that niacin may be an effective way for weaned piglets to maintain the gut and overall health.

Dietary Hermetia illucens Larvae Meal Improves Growth Performance and Intestinal Barrier Function of Weaned Pigs Under the Environment of Enterotoxigenic Escherichia coli K88.

The aim of this study was to evaluate the effect of Hermetia illucens larvae meal (HI) on the growth performance and intestinal barrier function of weaned pigs. To achieve this, 72 weaned pigs [28-day-old, 8.44 ± 0.04 kg body weight (BW)] were randomly assigned to three dietary treatments: basal diet (negative control, NC), zinc oxide-supplemented diet (positive control, PC), and HI-supplemented diet [100% replacement of fishmeal (FM), HI], for 28 days in the presence of enterotoxigenic Escherichia coli (ETEC). The results showed that HI and PC increased (p < 0.05) the average daily gain (ADG) and average daily feed intake (ADFI) of weaned pigs from day 1 to 14, and decreased diarrhea incidence from day 1 to 28. Additionally, HI increased (p < 0.05) claudin-1, occludin, mucin-1 (MUC-1), and MUC-2 expression, goblet cell number, and secretory immunoglobulin A (sIgA) concentration in the intestine of weaned pigs. Compared with NC, HI downregulated (p < 0.05) interleukin-1ß (IL-1ß) and IL-8 expression, and upregulated IL-10, transforming growth factor-ß (TGF-ß), antimicrobial peptide [porcine ß defensin 1 (pBD1), pBD2, protegrin 1-5 (PG1-5)] expression in the jejunum or ileum. Moreover, HI decreased (p < 0.05) toll-like receptor 2 (TLR2), phosphorylated nuclear factor-κB (p-NF-κB), and phosphorylated mitogen-activated protein kinase (p-MAPK) expression, and increased sirtuin 1 (SIRT1) expression in the ileum. Additionally, HI increased histone deacetylase 3 (HDAC3) expression and acetylation of histone 3 lysine 27 (acH3k27) in the ileum. Furthermore, HI positively influenced the intestinal microbiota composition and diversity of weaned pigs and increased (p < 0.05) butyrate and valerate concentrations. Overall, dietary HI improved growth performance and intestinal barrier function, as well as regulated histone acetylation and TLR2-NF-κB/MAPK signaling pathways in weaned pigs.

Effects of dietary supplementation with l-arginine on the intestinal barrier function in finishing pigs with heat stress.

Previous studies showed heat stress reduces body weight gain and feed intake associated with damaged intestinal barrier function, and l-arginine (L-Arg) enhanced intestinal barrier function in young animals under stress. The aim of this study was to evaluate effects of L-Arg on serum hormones, intestinal morphology, nutrients absorption and epithelial barrier functions in finishing pigs with heat stress. Forty-eight finishing pigs (Landrace) were balanced for sex and then randomly assigned to six groups: TN group, thermal neutral (22°C, ~80% humidity) with a basal diet; HS group, heat stress (cyclical 35°C for 12 hr and 22°C for 12 hr, ~80% humidity) with a basal diet; PF group, thermal neutral (22°C, ~80% humidity) and pair-fed with the HS; the TNA, HSA and PFA groups were the basal diet of TN group, HS group and PF group supplemented with 1% L-Arg. Results showed that HS decreased (p < .05) the thyroxine concentrations and increased (p < .05) the insulin concentrations in serum compared with the TN group, but 1% L-Arg had no significant effects on them. Both HS and PF significantly increased (p < .05) the mRNA expression of cationic amino acid transporters (CAT1 and CAT2) and decreased the mRNA expression of solute carrier family 5 member 10 (SGLT1) in the jejunum compared with the TN group. Compared with the TN group, HS reduced the expression of tight junction (TJ) protein zonula occluden-1 (ZO-1) and occludin, but PF only decreased ZO-1 expression in the jejunum. Results exhibited that dietary supplementation with 1% L-Arg improved the intestinal villous height, the ratio of villous height to crypt depth, and the expression of occludin and porcine beta-defensin 2 (pBD2) in the jejunum of intermittent heat-treated finishing pigs. In conclusion, dietary supplementation with 1% L-Arg could partly attenuate the intermittent heat-induced damages of intestinal morphology and epithelial barrier functions in finishing pigs.

Integrated metabolomic and proteomics profiling reveals the promotion of Lactobacillus reuteri LR1 on amino acid metabolism in the gut-liver axis of weaned pigs.

Lactobacillus reuteri LR1 improved growth performance of weaned pigs in our previous study. The objective of this study was to reveal effects of L. reuteri LR1 on amino acid (AA) metabolism in weaned pigs and its underlying mechanism using metabolomic and proteomics methods. Weaned pigs were fed a basal diet (CON) or the basal diet supplemented with 5 × 1010 cfu kg-1L. reuteri LR1 (LR1) for a 14 d period. Untargeted metabolomic analysis of the liver showed that LR1 up-regulated 33 metabolites and most of them were related to AA metabolism. Quantitative proteomics found that differential proteins were mainly involved in a metabolic process in the ileal mucosa of LR1 vs. CON. Integrated metabolomic and proteomics analysis showed that the LR1's enhancement of AA metabolism in the gut-liver axis is mediated by the up-regulated intestinal AA transporters in the pathway of protein digestion and absorption. Moreover, qPCR results confirmed that LR1 increased (p < 0.05) mRNA abundances of AA transporters (PepT1, EAAT3, rBAT, B0AT1, and b0,+AT) in the ileal mucosa compared with CON. Furthermore, western blot analysis showed that LR1 activated the mammalian target of the rapamycin complex 1 (mTORC1) signaling pathway by increasing the phosphorylation of S6 and 70S6K1 in the gut-liver axis of weaned pigs. Together, these data indicated that dietary supplemented LR1 enhanced AA metabolism by up-regulating intestinal AA transporter expression and activating the mTORC1 signaling pathway in the gut-liver axis of weaned pigs.

Panax notoginsenoside Rb1 Restores the Neurotrophic Imbalance Following Photothrombotic Stroke in Rats.

Mature brain-derived neurotrophic factor (mBDNF) has neuroprotection in cerebral ischemia. Conversely, the precursor of brain-derived neurotrophic factor (proBDNF) has the opposite function to its mature form, inducing apoptosis. However, whether the neuroprotection of Panax notoginsenoside Rb1 (PNS-Rb1) on ischemic stroke is due to, at least partially, its modulation of suppressing proBDNF/P75NTR/sortilin or upregulation of mBDNF is not clear. To test this hypothesis, rats induced by photothrombotic stroke were treated with PNS-Rb1 100 mg/kg or nimodipine 1 mg/kg twice a day until 3, 7, and 14 days. Our data indicate that PNS-Rb1 significantly reduced cerebral infarction rate, proBDNF/P75NTR/sortilin, and plasminogen activator inhibitor-1 (PAI-1) protein levels, and improved sensorimotor dysfunctions induced by ischemic stroke, upregulation of BDNF/TrkB levels, and its processing enzymes (tissue plasminogen activator, tPA) in a time-dependent manner. Taken together, our findings indicate that the improvement of sensorimotor dysfunctions by PNS-Rb1 following ischemic stroke is made, at least partially, by activating the BDNF/TrkB and inhibiting proBDNF/sortilin/P75NTR.

Lactobacillus reuteri LR1 Improved Expression of Genes of Tight Junction Proteins via the MLCK Pathway in IPEC-1 Cells during Infection with Enterotoxigenic Escherichia coli K88.

Intestinal epithelial barrier damage disrupts immune homeostasis and leads to many intestinal disorders. Lactobacillus reuteri strains have probiotic functions in their modulation of the microbiota and immune system in intestines. In this study, the effects of L. reuteri LR1, a new strain isolated from the feces of weaning piglets, on intestinal epithelial barrier damage in IPEC-1 cells caused by challenge with enterotoxigenic Escherichia coli (ETEC) K88 were examined. It was found that L. reuteri LR1, in large part, offset the ETEC K88-induced increase in permeability of IPEC-1 cell monolayers and decreased the adhesion and invasion of the coliform in IPEC-1 cells. In addition, L. reuteri LR1 increased transcript abundance and protein contents of tight junction (TJ) proteins zonula occluden-1 (ZO-1) and occludin in ETEC K88-infected IPEC-1 cells, whereas it had no effects on claudin-1 and F-actin expression. Using colloidal gold immunoelectron microscopy, these effects of L. reuteri LR1 on ZO-1 and occludin content in IPEC-1 cells were confirmed. By using ML-7, a selective inhibitor of myosin light-chain kinase (MLCK), the beneficial effect of L. reuteri LR1 on contents of ZO-1 and occludin was shown to be dependent on the MLCK pathway. In conclusion, L. reuteri LR1 had beneficial effects on epithelial barrier function consistent with increasing ZO-1 and occludin expression via a MLCK-dependent manner in IPEC-1 cells during challenge with ETEC K88.