A cell preparation ofEnterococcus faecalisstrain EC-12 stimulates the luminal immunoglobulin A secretion in juvenile calves

Effect of hospitalization on equine local intestinal immunoglobulin A (IgA) concentration measured in feces

During hospitalization horses may develop gastrointestinal conditions triggered by a stress-associated weak local immune system. The prospective, clinical trial was conducted to find out whether fecal immunoglobulin A (IgA) concentrations could be determined in hospitalized horses and how they changed during hospitalization and in response to various stressors. Samples were obtained from 110 horses and a control group (n = 14). At arrival in the hospital, horses were categorized into pain grades (1-5), and elective versus strenuous surgery (> 2 hours, traumatic and emergency procedures). Feces were collected on day 1, day 2, day 3, and day 7 in all horses. Blood samples were obtained at the same intervals, but additionally after general anaesthesia in horses undergoing surgery (day 2). IgA concentration in feces was determined by ELISA and measured in optical density at 450nm. The control group showed constant IgA concentrations on all days (mean value 0.30 OD450 ±SD 0.11, 1.26 mg/g; n = 11). After general anaesthesia fecal IgA concentrations decreased considerably independent of duration and type of surgery (P < 0.001 for elective and P = 0.043 for traumatic surgeries). High plasma cortisol concentrations were weakly correlated with low fecal IgA on the day after surgery (P = 0.012, day 3, correlation coefficient r = 0.113). Equine fecal IgA concentrations showed a decline associated with transport, surgery, and hospitalization in general, indicating that stress has an impact on the local intestinal immune function and may predispose horses for developing gastrointestinal diseases such as enterocolitis.

Effects of vitamin E supplementation on serum oxidative stress biomarkers, antibody titer after live bovine respiratory syncytial virus vaccination, as well as serum and fecal immunoglobulin A in weaned Japanese Black calves

The purpose of this study was to determine the effects of vitamin E supplementation on blood oxidative stress biomarker in weaned calves. Thirty clinically healthy 12 weeks of age Japanese Black calves were randomly assigned to two groups: 15 calves received 300 IU of vitamin E daily from 12 to 18 weeks of age (VE group), and the other 15 calves did not receive the vitamin E (control group). Blood samples were taken at 12, 14, 16, 18, and 20 weeks of age. The concentration of serum reactive oxygen metabolites at 20 weeks of age were significantly lower in the VE group than those in the control group. Vitamin E supplementation to weaned calves might affect blood oxidative stress.

Effects of the intake of non-live Bifidobacterium bifidum on the faecal IgA of full-term infants: a double-blind, randomised, placebo-controlled study

Bifidobacterium bifidum OLB6378 (OLB6378) was selected as a strain that enhances the production of secretory immunoglobulin A (IgA) in vitro. This ability of non-live OLB6378 has been shown by a clinical trial in preterm infants. In the present study, we examined whether non-live OLB6378 also enhances the production of secretory IgA, even in full-term infants. One hundred full-term infants were allocated to receive formula with (BbF group, 49 infants) or without non-live OLB6378 (PF group, 51 infants). Breastfeeding was prioritised, so infant formula was used for infants with breastfeeding difficulties. The intervention was initiated by five days of age. The faecal IgA concentration and OLB6378 level were determined at one, two, four, and eight weeks of age. Faecal IgA in the BbF group (1.04 ± 0.47 mg/g of faeces, n=45) was significantly higher than that in the PF group (0.85 ± 0.42 mg/g of faeces, n=49) at four weeks of age (p=0.047). OLB6378 was not detected in faeces at any age. This indicated that production of secretory IgA in full-term infants may also be enhanced by non-live OLB6378 intake.

A pilot study to investigate the measurement of immunoglobulin A in Welsh Cob and Welsh Pony foals' faeces and their dam's milk

Aims: To determine if an ELISA for measurement of IgA in equine serum could be used to measure concentrations of IgA in foal faeces and to determine correlations with concentrations in the milk of the dam.Methods: Faeces from 20 Welsh Cob and Welsh Pony foals and milk from their dams were collected within 12 hours (Day 0) and at 6 days after parturition (Day 6). On Day 6, faeces could not be collected from 2/20 foals, and milk samples could not be collected from 3/20 mares. An equine IgA ELISA validated for serum and plasma was used to measure concentrations of IgA in all samples in triplicate. The precision of the assay for each sample type was determined using modified CV.Results: IgA was not detectable in 7/20 Day 0 faecal samples and in 2/18 Day 6 faecal samples. For samples with detectable IgA, the mean modified CV was 10.5 (95% CI = 6.0-15.0)% for Day 0 faecal samples, and was 6.8 (95% CI = 4.3-9.4)% for Day 6 faecal samples. Median concentrations of IgA in faeces on Day 0 were lower than concentrations on Day 6 (0.7 mg/g vs. 37 mg/g dry matter; p = 0.003). Concentrations of IgA in milk and faeces on Day 6 were statistically correlated (r = 0.59; p = 0.006).Conclusions and clinical relevance: The IgA ELISA showed acceptable precision when used to estimate concentrations of IgA in foal faeces during the first week of life, but IgA could not be detected in 37% of meconium samples collected on Day 0. This assay may be useful for investigation of the role of maternal milk IgA in the gastrointestinal tract of neonatal foals, but further assessment of both accuracy and precision of the ELISA is required.

Heat-killed Enterococcus fecalis (EC-12) supplement alters the expression of neurotransmitter receptor genes in the prefrontal cortex and alleviates anxiety-like behavior in mice

Gut microbiota plays a crucial role in the maintenance of mental health and influences mental disorders such as depression and anxiety. Several studies have reported the beneficial affects of probiotics in mental health. Heat-killed Enterococcus faecalis strain EC-12 (EC-12), a lactic acid bacterium induces activation of the immune system. However, little is known about the effect of EC-12 on mental health. In the present study, the anti-anxiety effect of EC-12 was elucidated in vivo. Male mice fed on diet supplemented with EC-12 showed decreased anxiety-like behavior in open-field and elevated plus-mazetest. In addition, EC-12 supplementation exhibited an anti-depressive trend in mice subjected to forced swim test. The expression of neurotransmitter receptor genes: Adrb3 and Avpr1a were significantly enhanced in EC-12 supplemented mice compared to that of the control mice. In mice, analyses of gut microbiota composition by next generation sequencing revealed significant increase in Butyricicoccus and Enterococcus with EC-12 supplementation. Significant difference was not detected in the expression of neurotransmitter receptor genes in the prefrontal cortex with the administration of sodium butyrate compared to that of the control group. The mechanism associated with EC-12 mediated reduced anxiety-like behavior and altered gene expression in the brain needs to be further elucidated. Taken together, the present study is the first to report the possibility of exploiting the anti-anxiety effect of heat-killed EC-12 as a novel probiotic to promote mental health.

Growth, health, rumen fermentation, and bacterial community of Holstein calves fed Lactobacillus rhamnosus GG during the preweaning stage1

The aim of this study was to determine if feeding Lactobacillus rhamnosus GG (GG, ATCC 53013) to neonatal calves would alter their growth, health, rumen fermentation, and bacterial community composition during the preweaning stage; we hypothesized that it would. Twenty-four male Holstein calves were blocked and randomly assigned to 1 of 2 treatment groups: 1) untreated control (CON), or 2) treated with 1 × 1010 cfu/d of a GG suspension (GG). Calves received GG daily, mixed with the milk replacer in the morning feed for 6 wk. Starter and alfalfa hay intakes, as well as feces and respiratory scores, were recorded daily, while body weight and structures were measured weekly. Blood, rumen fluid, and feces samples were collected, from which relevant indicators were detected. The results showed that the administration of GG significantly increased voluntary starter intake (P = 0.023) and ADG (P = 0.035) of the calves. The fecal score (P = 0.018) was lower and the β-hydroxybutyric concentration in the plasma tended to increase (P = 0.092) in calves treated with GG. The pH of the rumen fluid in calves fed GG was lower (P = 0.007), which might be attributable to the tendency (P = 0.083) for total volatile fatty acids concentration to increase. Administration of GG significantly increased the amylase, protease activity, and the microbial protein concentrations (P = 0.043, P = 0.036, and P = 0.044, respectively) in the rumen fluids. Furthermore, GG treatment altered the dominant bacteria order and relative abundance of the bacteria families in the rumen fluids. The microbial diversity indices were significantly affected by GG administration. In conclusion, the neonatal calves fed GG before weaning increased their voluntary starter intake and growth performance, improved the rumen fermentation, and regulated the pattern to normally increase the propionate and butyrate concentrations. Administration of GG also diversified the bacterial community composition in the rumen, and regulated the balance of rumen and intestinal microorganisms. These results indicated that feeding calves GG were beneficial to the rumen development and early weaning.

Dietary Probiotic Compound Improves Reproductive Performance of Porcine Epidemic Diarrhea Virus-Infected Sows Reared in a Japanese Commercial Swine Farm under Vaccine Control Condition

Lactogenic immunity transferred to piglets after inoculation of a live vaccine to pregnant sows was proved limited to control porcine epidemic diarrhea (PED). Hence, here we evaluated the efficacy of administration of a probiotic compound containing Bacillus mesentericus, Clostridium butyricum, and Enterococcus faecalis together with a commercial live-attenuated PED vaccine (Nisseiken PED Live Vaccine, Nisseiken, Tokyo, Japan) to improve the health and reproductive performance of PED-infected sows. Twenty pregnant sows in a PED-positive farm were equally divided into probiotics-administered (VP) and control (VC) sow groups. A commercial live-attenuated vaccine was injected as per the manufacturer’s instruction. The probiotic compound (15 g/day) was orally administered to VP from 6 weeks pre-parturition to 7 days post-parturition (ppd7). VP had a significantly higher body weight at ppd7 than VC (191 vs 186 kg; P < 0.05). At day 3 post-parturition (ppd3) (4.18 vs 3.63 kg/day) and ppd7 (5.14 vs 4.34 kg/day), milk produced by VP was significantly (P < 0.05) greater than that by VC. Total immunoglobulin (Ig)A and IgG concentrations at day 0 were significantly (P < 0.05) higher in whey of VP (1.9 and 6.6 g/dL, respectively) than in that of VC (1.7 and 6.1 g/dL, respectively). However, total IgG concentration in whey of VP and VC at ppd3 and ppd7 did not differ. Antibody titer was significantly higher at day 0 in serum of VP than it was that of VC (60 vs 37 in geometric mean; P < 0.05). Likewise, the antibody titer in whey of VP and VC was found to be similar at day 0 (416 vs 208 in geometric mean; P = 0.13). Consequently, VP had fewer days between weaning and return to estrus than did VC (7 vs 10 days; P < 0.05). Moreover, piglets of VP had a significantly (P < 0.05) higher litter weight at birth (9,252 g/litter) and a lower mortality (12%) during suckling than those of VC (8,686 g/litter and 28%, respectively). In summary, probiotic-supplemented, PED-vaccinated sows were healthier, transferred PED-specific antibodies via colostrum to piglets, had greater litter weight at birth, and reduced mortality during suckling.

Oral Administration of EC-12 Increases the Baseline Gene Expression of Antiviral Cytokine Genes, IFN-γ and TNF-α, in Splenocytes and Mesenteric Lymph Node Cells of Weaning Piglets

Weaning piglets are continuously exposed to various viruses. The antiviral effects of lactic acid bacteria (LAB) have been confirmed mainly in humans and mice, while few studies have been conducted in livestock. In this study, we evaluated the effect of oral administration of Enterococcus faecalis strain EC-12 (EC-12) on the gene expressions of antiviral cytokines in weaning piglets. Piglets were allocated to the EC-12-administered group (E group) and the no-treatment control group (C group). The small intestinal tissue, the mesenteric lymph node (MLN) cells and the splenocytes were collected from the piglets. The tissue and cells were co-cultured with a live vaccine of porcine reproductive respiratory syndrome virus, porcine epidemic diarrhea virus or EC-12. After the incubation, the gene expressions of IFN-γ and TNF-α in the tissue and cells were evaluated. The gene expressions of IFN-γ in the MLN cells and TNF-α in the splenocytes were significantly higher in the E group than in the C group. However, the increase in the gene expression of antiviral cytokines was observed independently of the antigen treatments. The results of the present study suggest that oral administration of EC-12 did not increase the response of immune cells to specific viral antigens but increased the baseline gene expression of antiviral cytokines.

Role of the mannose receptor in phagocytosis of Enterococcus faecalis strain EC-12 by antigen-presenting cells

The aim of this study was to clarify the phagocytic mechanisms of a heat-killed cell preparation of Enterococcus faecalis strain EC-12 (EC-12) by antigen-presenting cells (APCs). Fluorescein isothiocyanate (FITC)-labeled EC-12 was cocultured with peritoneal macrophage and the amount of EC-12 phagocytosed by peritoneal macrophages was measured using a microplate fluorometer. Peritoneal macrophages from toll-like receptor (TLR)2-, TLR7-, and MyD88-deficient knockout (KO) mice exhibited similar levels of EC-12 phagocytosis to those from wild-type mice. Similarly, dectin-1 neutralization of peritoneal macrophages had no effect on EC-12 phagocytosis. However, blockade of the mannose receptor (MR) significantly decreased the amount of EC-12 phagocytosed by peritoneal macrophages; the same effect was observed in bone marrow-derived macrophages and dendritic cells. Our findings suggest that MR plays a major role in EC-12 phagocytosis by the APCs.

This aim of this study was to clarify the phagocytic mechanisms of a heat-killed cell preparation of Enterococcus faecalis strain EC-12 (EC-12) by antigen-presenting cells (APCs). Our findings suggest that mannose receptor (MR) plays a major role in EC-12 phagocytosis by the APCs.

Commensal bacteria coated by secretory immunoglobulin A and immunoglobulin G in the gastrointestinal tract of pigs and calves

A large amount of secretory immunoglobulin A (S-IgA) is secreted in the alimentary tract of mammals. It has been reported that S-IgA coats a portion of commensal intestinal bacteria in human and mouse. However, S-IgA-coated bacteria have not been studied in pigs and calves. In this study, we evaluated the distribution of S-IgA-coated commensal intestinal bacteria in each portion of the gastrointestinal tracts of pigs and calves. Immunoglobulin G (IgG)-coated bacteria were also analyzed because a considerable amount of IgG is secreted in the gastrointestinal tracts of pigs, and in particular, calves. S-IgA- or IgG-coated bacteria were detected in all the segments of the gastrointestinal tracts of pigs and calves. The proportion of S-IgA-coated bacteria to total bacteria (i.e. S-IgA coating ratio) varied in the segments of the gastrointestinal tract in pigs, whereas those of calves were nearly the same throughout the gastrointestinal tract. The S-IgA and IgG coating ratios were higher in pigs than in calves for all segments of the gastrointestinal tract.

Evaluation of the heat-killed and dried cell preparation of Enterococcus faecalis against villous atrophy in early-weaned mice and pigs

Early weaning induces villous atrophy in the small intestine (SI) of piglets. Oral administration of live lactic acid bacteria (LAB) can improve villous shortening. In this study, we evaluated the oral administration of a heat-killed and dried cell preparation of Enterococcus faecalis (a LAB) strain EC-12 against villous atrophy in early-weaned mice (Experiment 1) and pigs (Experiments 2 and 3). Twelve 16-days-old mice were divided into two groups in Experiment 1: gavage of EC-12 (10 mg/kg body weight (BW)/day), or control. On day 21, SI was collected. Eighteen 21-day-old pigs were divided into two groups in Experiment 2: gavage of EC-12 (10 mg/kg BW/day), or control. After 10 days, the villous height of jejunum was measured. Six 21-day-old pigs were divided into two groups in Experiment 3: the basal diet supplemented with EC-12 at 0.05%-fed group, or the basal diet-fed group. After 10 days, the villous height of jejunum was measured. The villous heights in SI were significantly higher by EC-12 administration in all experiments. EC-12 successfully improved the villous atrophy in the early-weaned mice and pigs when EC-12 was administered orally.