Porcine astrovirus 3 RNA in the central nervous system of weaned pigs with neurologic disease and polioencephalomyelitis in Brazil

This report aims to describe the identification of porcine astrovirus 3 (PAstV3) RNA in the central nervous system (CNS) of weaned pigs with clinical signs of neurological disease associated with polioencephalomyelitis in southeastern Brazil. Three, 20 -35 days-old piglets that died after clinical manifestations of a neurological syndrome were submitted to post-mortem evaluations. Tissue samples were examined by histopathology, bacteriology, and molecular assays (RT-PCR, nested-PCR, RT-qPCR, and Sanger sequencing) to detect the primary infectious disease agents associated with neurological disease in pigs. The principal neuropathological alterations occurred in the grey matter of the spinal cord and brainstem resulting in nonsuppurative poliomyelitis and rhombencephalitis. PAstV3 RNA was detected in the CNS samples of all piglets with histopathological evidence of disease and was confirmed by nucleotide sequencing. Nucleic acids from pathogens commonly associated with neurological diseases in pigs, such as porcine teschovirus, porcine sapelovirus, porcine enterovirus G, atypical porcine pestivirus, senecavirus A, and encephalomyocarditis virus was not detected by molecular assays in the three piglets. This is the first report of PAstV3 in piglets with neurological disease and lesions consistent with polioencephalomyelitis in Brazil. This report highlights the importance of monitoring health events that could compromise pig farming productivity and animal welfare.

Effect of iron-manganese oxide on the degradation of deoxynivalenol in feed and enhancement of growth performance and intestinal health in weaned piglets

Deoxynivalenol (DON), a prevalent and highly toxic mycotoxin in animal feed, poses significant risks to livestock health and productivity. This study evaluates the effectiveness of iron-manganese oxide (Fe/Mn oxides) in degrading DON. The DON degradation rate of Fe/Mn oxide reached 98.46 % in a controlled solution under specific conditions (0.2 % concentration, 37-85 °C, pH 6-7, 1-minute reaction time). When applied to actual feed, it reduced DON levels by approximately 49.3 % and remained stable in simulated gastrointestinal environments of weaned piglets. A 28-day trial involving 48 weaned piglets assessed the impacts of Fe/Mn oxides on health and growth. Results indicated that piglets consuming contaminated feed without the treatment exhibited reduced growth and compromised gut integrity, which were significantly mitigated by the addition of Fe/Mn oxides. Therefore, Fe/Mn oxides effectively reduce DON in feed and alleviate adverse health effects in piglets, making them a viable option to enhance safety and performance in mycotoxin-prone environments.

Impact of adding eicosapentaenoic and docosahexaenoic acid-rich fish oil in sow and piglet diets on blood oxylipins and immune indicators of weaned piglets

Weaning is a decisive event in piglets' life. This study aimed to evaluate whether the inclusion of fish oil, rich in eicosapentaenoic and docosahexaenoic acids (EPA and DHA), in sow and piglet diets, increased the concentration of anti-inflammatory molecules in the blood of weaned piglets and whether the effect was dependent on the pigs being born with either low or a high birth BW (bBW). Thirty-six sows in four consecutive batches were randomly distributed between a control diet with animal fat (15 g/kg in gestation and 30 g/kg in lactation) or a n-3 long-chain fatty acid diet (LCFA; totally or half replacing animal fat by fish oil during gestation and lactation, respectively) from service until weaning (ca. 28 days). At birth, the two lightest (LBW) and the two heaviest (HBW) piglets in each litter were identified and, at weaning, grouped in pens by pairs prioritising their bBW. Pens were further distributed into a control (30 g/kg animal fat) or n-3 LCFA diet (totally replacing animal fat by fish oil) for 28 days. At the end of the trial, blood was collected from piglets in the first batch (n = 48). Serum fatty acids (FAs) were quantified by GC, plasma oxylipins by ultra-HPLC-MS, and plasma immune indicators by ELISA. An interaction between piglet diet and bBW for average daily gain (P = 0.020) and average daily feed intake (P = 0.014) during the whole postweaning indicated that dietary n-3 LCFA-promoted LBW piglets to have a similar growth and intake than HBW piglets reaching 1.5 kg average BW more at the end of the postweaning period than LBW control piglets. Fish oil in piglet diets also increased the concentrations of total n-3 FA, EPA and DHA (all P < 0.001), their resultant oxylipins, particularly their hydroxy derivatives from lipoxygenase enzymatic pathway (all P < 0.001) and tended to increase immunoglobulin M (P = 0.067) in blood. Regarding the bBW category, LBW piglets tend to increase tumour necrosis factor α in plasma (P = 0.083) compared to HBW. It is concluded that fish oil in postweaning diets could enhance the daily gain and feed intake of LBW piglets, increasing the concentration of serum n-3 FAs and their derived oxylipins in plasma.

Dynamic of swine influenza virus infection in weaned piglets in five enzootically infected herds in Germany, a cohort study

BACKGROUND

Within the last decades industrial swine herds in Europe grown significantly, creating an optimized reservoir for swine influenza A viruses (swIAV) to become enzootic, particularly in piglet producing herds among newborn, partly immunologically naïve piglets. To date, the only specific control measure to protect piglets from swIAV is the vaccination of sows, which provides passive immunity through maternally derived antibodies in colostrum of vaccinated sows. Interruption of infection chains through management practices have had limited success. This study focused on weaned piglets in five enzootically swIAV infected swine herds in North-West and North-East Germany and aimed to better understand swIAV infection patterns to improve piglet protection and reduce zoonotic risks. Participating farms fulfilled the following inclusion criteria: sow herd with ≥ 400 sows (actual size 600-1850 sows), piglets not vaccinated against influenza A virus and a history of recurrent respiratory problems associated with continuing influenza A virus infection. Influenza vaccination was performed in all sow herds, except for one, which discontinued vaccination during the study.

RESULTS

First swIAV detections in weaned piglets occurred at 4 weeks of age in the nursery and continued to be detected in piglets up to 10 weeks of age showing enzootic swIAV infections in all herds over the entire nursery period. This included simultaneous circulation of two subtypes in a herd and co-infection with two subtypes in individual animals. Evidence for prolonged (at least 13 days) shedding was obtained in one piglet based on two consecutive swIAV positive samplings. Possible re-infection was suspected in twelve piglets based on three samplings, the second of which was swIAV negative in contrast to the first and third sampling which were swIAV positive. However, swIAV was not detected in nasal swabs from either suckling piglets or sows in the first week after farrowing.

CONCLUSIONS

Predominantly, weaned piglets were infected. There was no evidence of transmission from sow to piglet based on swIAV negative nasal swabs from sows and suckling piglets. Prolonged virus shedding by individual piglets as well as the co-circulation of different swIAV subtypes in a group or even individuals emphasize the potential of swIAV to increase genetic (and potentially phenotypic) variation and the need to continue close monitoring. Understanding the dynamics of swIAV infections in enzootically infected herds has the overall goal of improving protection to reduce economic losses due to swIAV-related disease and consequently to advance animal health and well-being.

Effects of inactivated Lactobacillus rhamnosus on growth performance, serum indicators, and colonic microbiota and metabolism of weaned piglets

BACKGROUND

To assess the effects of inactivated Lactobacillus rhamnosus (ILR) on growth performance, serum biochemical indices, colonic microbiota, and metabolomics in weaned piglets, 120 piglets were randomly divided into five groups. Samples in the control group were fed a basal diet, while the experimental ILR1, ILR2, ILR3, and ILR4 groups were fed basal diets supplemented with 0.1%, 0.2%, 0.3%, and 0.4% ILR, respectively. The prefeeding period lasted for 5 days and was followed by a formal period of 28 days.

RESULTS

Compared to the control, the average daily gain increased by 4.38%, 7.98%, 19.32%, and 18.80% for ILR1, ILR2, ILR3, and ILR4, respectively, and the ratio of feed to gain decreased by 0.63%, 3.80%, 12.66%, and 10.76%, respectively. Serum IgA, IgG, IgM, total antioxidant capacity, and glutathione peroxidase levels increased significantly in weaned piglets in the treatment groups. Addition of 0.3% ILR significantly increased the Shannon and Simpson indices of the colonic microbiota in weaned piglets and altered the microbiota composition. Changes in metabolic profiles were observed and were primarily related to the urea cycle, amino acid metabolism, and lipid metabolism.

CONCLUSION

ILR improved growth performance and serum immunological and biochemical indices and optimized the colonic microbiota structure and metabolism of weaned piglets.

Pyrroloquinoline quinone supplementation attenuates inflammatory liver injury by STAT3/TGF-β1 pathway in weaned piglets challenged with lipopolysaccharide

This study is aimed to evaluate the effect and underling mechanism of dietary supplementation with pyrroloquinoline quinone (PQQ) disodium on improving inflammatory liver injury in piglets challenged with lipopolysaccharide (LPS). A total of seventy-two crossbred barrows were allotted into four groups as follows: the CTRL group (basal diet + saline injection); the PQQ group (3 mg/kg PQQ diet + saline injection); the CTRL + LPS group (basal diet + LPS injection) and the PQQ + LPS group (3 mg/kg PQQ diet + LPS injection). On days 7, 11 and 14, piglets were challenged with LPS or saline. Blood was sampled at 4 h after the last LPS injection (day 14), and then the piglets were slaughtered and liver tissue was harvested. The results showed that the hepatic morphology was improved in the PQQ + LPS group compared with the CTRL + LPS group. PQQ supplementation decreased the level of serum inflammatory factors, aspartate aminotransferase and alanine transaminase, and increased the HDL-cholesterol concentration in piglets challenged with LPS; piglets in the PQQ + LPS group had lower liver mRNA level of inflammatory factors and protein level of α-smooth muscle actin than in the CTRL + LPS group. Besides, mRNA expression of STAT3/TGF-β1 pathway and protein level of p-STAT3(Tyr 705) were decreased, and mRNA level of PPARα and protein expression of p-AMPK in liver were increased in the PQQ + LPS group compared with the CTRL + LPS group (P < 0·05). In conclusion, dietary supplementation with PQQ alleviated inflammatory liver injury might partly via inhibition of the STAT3/TGF-β1 pathway in piglets challenged with LPS.

Growth performance, lipid metabolism, and systemic immunity of weaned piglets were altered by buckwheat protein through the modulation of gut microbiota

Tartary buckwheat protein (BWP) is well known for the wide-spectrum antibacterial activity and the lipid metabolism- regulating property; therefore, BWP can be applied as feed additives to improve the animal's nutritional supply. With the aim to investigate the bioactive actions of the BWP, growth performance, lipid metabolism and systemic immunity of the weaned piglets were measured, and the alterations of pig gut microbiota were also analyzed. According to the results, the growth performances of the weaned piglets which were calculated as the average daily gain (ADG) and the average daily feed intake (ADFI) were significantly increased when compared to the control group. Simultaneously, the serum levels of the total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were decreased, while the levels of high-density lipoprotein cholesterol (HDL-C) were increased in the BWP group. Moreover, the relative abundances of Lactobacillus, Prevotella_9, Subdoligranulum, Blautia, and other potential probiotics in the gut microbiota of weaned piglets were obviously increased in the BWP group. However, the relative abundances of Escherichia-Shigella, Campylobacter, Rikenellaceae_RC9_gut_group and other opportunistic pathogens were obviously decreased in the BWP group. In all, BWP was proved to be able to significantly improve the growth performance, lipid metabolism, and systemic immunity of the weaned piglets, and the specific mechanism might relate to the alterations of the gut microbiota. Therefore, BWP could be explored as a prospective antibiotic alternative for pig feed additives.

Dietary supplementation of benzoic acid and essential oils combination enhances intestinal resilience against LPS stimulation in weaned piglets

BACKGROUND

The benefits of combining benzoic acid and essential oils (BAO) to mitigate intestinal impairment during the weaning process have been well established, while the detailed underlying mechanism has not been fully elucidated. Previous research has primarily focused on the reparative effects of BAO on intestinal injury, while neglecting its potential in enhancing intestinal stress resistance.

METHODS

In this study, we investigated the pre-protective effect of BAO against LPS-induced stress using a modified experimental procedure. Piglets were pre-supplemented with BAO for 14 d, followed by a challenge with LPS or saline to collect blood and intestinal samples.

RESULTS

Our findings demonstrated that BAO supplementation led to significant improvements in piglets' final weight, average daily gain, and feed intake/body gain ratio. Additionally, BAO supplementation positively influenced the composition of intestinal microbiota, increasing beneficial Actinobacteriota and Alloprevotella while reducing harmful Desulfobacterota, Prevotella and Oscillospira. Furthermore, BAO supplementation effectively mitigated oxidative disturbances and inflammatory responses induced by acute LPS challenge. This was evidenced by elevated levels of T-AOC, SOD, and GSH, as well as decreased levels of MDA, TNF-α, and IL-6 in the plasma. Moreover, piglets subjected to LPS challenge and pre-supplemented with BAO exhibited significant improvements in intestinal morphological structure and enhanced integrity, as indicated by restored expression levels of Occludin and Claudin-1 compared to the non-supplemented counterparts. Further analysis revealed that BAO supplementation enhanced the jejunal antioxidative capacity by increasing GSH-Px levels and decreasing MDA levels under the LPS challenge and stimulated the activation of the Nrf2 signaling pathway. Additionally, the reduction of TLR4/NF-κB/MAPK signaling pathways activation and proinflammatory factor were also observed in the jejunal of those piglets fed with BAO.

CONCLUSIONS

In summary, our study demonstrates that pre-supplementation of BAO enhances the anti-stress capacity of weaned piglets by improving intestinal microbiota composition, reinforcing the intestinal barrier, and enhancing antioxidative and anti-inflammatory capabilities. These effects are closely associated with the activation of Nrf2 and TLR4/NF-κB/MAPK signaling pathways.

Effect of replacing inorganic iron with iron-rich microbial preparations on growth performance, serum parameters and iron metabolism of weaned piglets

This study aimed to investigate the effects of replacing of dietary inorganic iron with iron-rich Lactobacillus plantarum and iron-rich Candida utilis on the growth performance, serum parameters, immune function and iron metabolism of weaned piglets. Fifty-four 28-day-old healthy Duroc × Landrace × Yorkshire castrated male weanling piglets of similar body weight were randomly and equally divided into three groups. The piglets were kept in three pens per group, with six pigs in each pen. The dietary treatments were (1) a basal diet + ferrous sulfate preparation containing 120 mg/kg iron (CON); (2) a basal diet + iron-rich Candida utilis preparation containing 120 mg/kg iron (CUI); and (3) a basal diet + iron-rich Lactobacillus plantarum preparation containing 120 mg/kg iron (LPI). The entire feeding trial lasted for 28 days, after which blood, viscera, and intestinal mucosa were collected. The results showed no significant difference in growth parameters and organ indices of the heart, liver, spleen, lung, and kidney of weaned piglets when treated with CUI and LPI compared with the CON group (P > 0.05). However, CUI and LPI significantly reduced the serum contents of AST, ALP, and LDH (P < 0.05). Serum ALT content was significantly lower in the LPI treatment compared to the CON group (P < 0.05). Compared to CON, CUI significantly increased the contents of serum IgG and IL-4 (P < 0.05), and CUI significantly decreased the content of IL-2. LPI significantly increased the contents of serum IgA, IgG, IgM and IL-4 (P < 0.05), while LPI significant decreased the levels of IL-1β, IL-2, IL-6, IL-8, and TNF-α compared to CON (P < 0.05). CUI led to a significant increase in ceruloplasmin activity and TIBC (P < 0.05). LPI significantly increased the contents of serum Fe and ferritin, and increased the serum ceruloplasmin activity and TIBC compared to CON (P < 0.05). Furthermore, CUI resulted in a significant increase in the relative mRNA expression of FPN1 and DMT1 in the jejunal mucosa (P < 0.05). LPI significantly increased the relative mRNA expression of TF, FPN1, and DMT1 in the jejunal mucosa (P < 0.05). Based on these results, the replacement of dietary inorganic iron with an iron-rich microbial supplement could improve immune function, iron absorption and storage in piglets.

Gut microbiota alteration with growth performance, histopathological lesions, and immune responses in Salmonella Typhimurium-infected weaned piglets

Salmonella Typhimurium can cause gastroenteritis in weaned piglets, which are particularly vulnerable to dietary changes and dysfunction of their immature organs. The colonization of S. Typhimurium could disrupt the gut microbiota and increase susceptibility to the bacterium. This study aimed to investigate the alterations of gut microbiota in S. Typhimurium-infected weaned piglets. Ten 49-day-old pigs were divided into two groups: S. Typhimurium-inoculated (ST, n = 6) and negative control (NC, n = 4) groups. The body weight and S. Typhimurium fecal shedding were monitored for 14 days after S. Typhimurium inoculation (dpi). The intestinal tissues were collected at 14 dpi; histopathological lesions and cytokine gene expression were evaluated. The gut microbiome composition and short-chain fatty acid concentrations were analyzed in fecal samples collected at 14 dpi. The average daily gain and gut microbiota alpha diversity in ST group tended to be lower than NC group at 14 dpi. Linear discriminant analysis effect size results showed a significant increase in the abundance of two genera and five species, while a significant decrease was observed in the five genera and nine species within the gut microbiota of ST group. Among the significantly less abundant bacteria in the ST group, Lachnospira eligens and Anaerobium acetethylicum produce acetate and butyrate, and may be considered as key S. Typhimurium infection-preventing bacteria. The overall results provide invaluable information about changes in the gut microbiota of S. Typhimurium-infected weaned piglets, which can be used to develop alternative measures to antibiotics and prevent ST bacterial infection.

Effects of combined application of benzoic acid and 1-monolaurin on growth performance, nutrient digestibility, gut microbiome and inflammatory factor levels in weaned piglets

BACKGROUND

Our previous study observed that benzoic acid and 1-monolaurin have a synergistic bactericidal effect. Moreover, their improvement effect of benzoic acid and 1-monolaurin on the growth performance and diarrhea of weaned piglets was better than the two feedings alone. However, it is not clear how the combination of benzoic acid and 1-monolaurin affects the growth performance of weaned piglets. Therefore, 100 weaned piglets (mean weight 7.03 ± 1.04 kg, mean weaning age 26 d) were randomly divided into two groups: (1) basal diet control (CON); (2) basal diet supplemented with 0.6% benzoic acid and 0.1% 1-monolaurin (CA). The experiment lasted 28 days after weaning. The effects of benzoic acid and 1-monolaurin supplementation on growth performance, apparent nutrient digestibility, intestinal flora composition and function, and inflammatory factor levels of weaned piglets were investigated.

RESULTS

The feed conversion efficiency of piglets in the CA group between 15 and 28 d and 1 and 28 d after weaning was significantly higher than that in the CON group (P < 0.05). Additionally, the diarrhea proportion and frequency of piglets in the CA group 1-14 days post-weaning were significantly decreased (P < 0.05). The apparent digestibility of dry matter, organic matter and crude protein of piglets in the CA group was significantly higher than the CON group on days 14 and 28 (P < 0.05). The microbial composition in the cecal digesta of piglets was detected. The results indicated that the CA group piglets were significantly supplemented with g_YRC22 at day 14 and g_Treponema, g_Pseudomonas, and g_Lachnobacterium at day 28 (P < 0.05; log LDA > 2). No significant difference was observed between the CON and CA groups in the content of short-chain fatty acids. In addition, serum IL-1β level significantly decreased at day 28 in the CA group compared with the CON group, while serum endotoxin content was significantly reduced at day 14.

CONCLUSION

Therefore, dietary supplementation of 0.6% benzoic acid and 0.1% 1-monolaurin enhanced growth performance and nutrient digestibility, affected gut microflora composition, and decreased systemic inflammatory response and intestinal permeability of weaned piglets. These outcomes provide a theoretical basis for applying of benzoic acid and 1-monolaurin over weaned piglets.

Garlic essential oil supplementation modulates colonic microbiota compositions and regulates immune response in weaned piglets

The objective of this study was to investigate the colonic microbiome compositions and immune response and reveal their correlations in weaned piglets fed with garlic essential oil (GEO). Twelve 21-day-old crossbred piglets with the same parity and similar weight (BW = 7.07 ± 0.37 Kg) were randomly divided into control and experimental groups based on BW and sex, which fed either a basal diet (CON group), or a basal diet supplemented with 1.5 g/kg GEO (GEO group). UHPLC-QE-MS showed the main component of GEO were belonged to carbohydrates, organic acid, flavonoids, phenylpropanoids and terpenoids. GEO decreased serum IL-1β, IL-8 content and the down-regulated mRNA expression of IFN-γ, TLR2 in jejunal mucosa but increased serum IgG, IL-4 content and up-regulated the mRNA expression of IL-4, IL-1β, TNF-α in ileal mucosa. What's more, the metagenomic analysis demonstrated that GEO increased the abundance of Bacteroidetes, Euryarchaeota and Spirochaetes, while decreased the abundance of Firmicutes and Actinobacteria at Phylum level and Selenomonas_boris, Selenomonadaceae_bacterium_DSM_108025, Clostridiales_bacterium and Phascolarctobacterium_succinatutens at species level. Notably, the main function pathway of virulence factor (VFDB) enriched in GEO group were Fibronection-binding protein, Zn++ metallophrotease and Capsular polysaccharide, while the main function pathway of VFDB enriched in CON group were heme biosynthesis, Lap and FeoAB. Spearman correlation analysis indicated the Spirochaetes had a positive association with IL-6 and IL-4. Acinobacteria was positively correlated with IL-1β, while negative with the IL-6; In addition, Euryarchaeota had a positive correlation with IL-4, but a negative correlation with IL-1β; Tenericutes was negative with IL-8; Phascolarcolarctobacterium_succinatutens and was negative with IL-6; Ruminococcaceae_bacterium was negative with TNF-α. While Selenomonadaceae_bacterium_DSM_108025 had a positive correlation with IL-8. In conclusion, our results uncovered that immune regulation effects of GEO may be associated with the microbiome compositions in response to GEO.

Effect of small peptide chelated iron on growth performance, immunity and intestinal health in weaned pigs

BACKGROUND

Small peptide chelated iron (SPCI), a novel iron supplementation in pig diets, owns growth-enhancing characteristics. Although a number of researches have been performed, there is no clear-cut evidence to show the exact relationship between the dose and effects of small peptide chelated minerals. Therefore, we investigated the effect of dietary supplementation of SPCI at different doses in the growth performance, immunity, and intestinal health in weaned pigs.

METHODS

Thirty weaned pigs were randomly assigned into five groups and feed with basal diet or the basal diet containing 50, 75, 100, or 125 mg/kg Fe as SPCI diets. The experiment lasted for 21 d and on day 22, blood samples were collected 1 h later. The tissue and intestinal mucosa samples were collected following.

RESULTS

Our results showed that the feed to gain ratio (F:G) decreased with different levels of SPCI addition (P < 0.05). The average daily gain (ADG) (P < 0.05) and digestibility of crude protein (P < 0.01) decreased with 125 mg/kg SPCI addition. With dietary different levels of SPCI addition, the serum concentrations of ferritin (quadratic, P < 0.001), transferrin (quadratic, P < 0.001), iron content in liver (quadratic, P < 0.05), gallbladder (quadratic, P < 0.01) and fecal (quadratic, P < 0.01) increased quadraticly. While the iron content in tibia (P < 0.01) increased by 100 mg/kg SPCI supplementation. Dietary 75 mg/kg SPCI addition increased the serum insulin-like growth factor I (IGF-I) (P < 0.01) and SPCI (75 ~ 100 mg/kg) addition also increased the serum content of IgA (P < 0.01). The serum concentrations of IgG (quadratic, P < 0.05) and IgM (quadratic, P < 0.01) increased quadraticly by different levels of SPCI supplementation. Moreover, different levels of SPCI supplementation decreased the serum concentration of D-lactic acid (P < 0.01). The serum glutathione peroxidase (GSH-Px) (P < 0.01) elevated but the malondialdehyde (MDA) (P < 0.05) decreased by 100 mg/kg SPCI addition. Interestingly, SPCI supplementation at 75 ~ 100 mg/kg improved the intestinal morphology and barrier function, as suggested by enhanced villus height (P < 0.01) and villus height/crypt depth (V/C) (P < 0.01) in duodenum, as well as jejunum epithelium tight-junction protein ZO-1 (P < 0.01). Moreover, SPCI supplementation at 75 ~ 100 mg/kg increased the activity of duodenal lactase (P < 0.01), jejunal sucrase (P < 0.01) and ileal maltase (P < 0.01). Importantly, the expression levels of divalent metal transporter-1(DMT1) decreased with different levels of SPCI addition (P < 0.01). In addition, dietary SPCI supplementation at 75 mg/kg elevated the expression levels of critical functional genes such as peptide transporter-1(PePT1) (P = 0.06) and zinc transporter 1 (ZnT1) (P < 0.01) in ileum. The expression levels of sodium/glucose co-transporter-1 (SGLT1) in ileum (quadratic, P < 0.05) increased quadraticly by different levels of SPCI addition and amino acid transporter-1 (CAT1) in jejunum(P < 0.05) also increased by 100 mg/kg SPCI addition.

CONCLUSIONS

Dietary SPCI supplementation at 75 ~ 100 mg/kg improved growth performance by elevated immunity and intestinal health.

Engineered Bacillus subtilis alleviates intestinal oxidative injury through Nrf2-Keap1 pathway in enterotoxigenic Escherichia coli (ETEC) K88-infected piglet

Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties. In this study, we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32 (WB800-KR32) using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2 (Nrf2)‍-Kelch-like ECH-associated protein 1 (Keap1) pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli (ETEC) K88 in weaned piglets. Twenty-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal diet. The feed of the control group (CON) was infused with normal sterilized saline; meanwhile, the ETEC, ETEC+WB800, and ETEC+WB800-KR32 groups were orally administered normal sterilized saline, 5×10¹⁰ CFU (CFU: colony forming units) WB800, and 5×10¹⁰ CFU WB800-KR32, respectively, on Days 1‍‒‍14 and all infused with ETEC K88 1×10¹⁰ CFU on Days 15‍‒‍17. The results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance, improved the mucosal activity of antioxidant enzyme (catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)) and decreased the content of malondialdehyde (MDA). More importantly, WB800-KR32 downregulated genes involved in antioxidant defense (GPx and SOD1). Interestingly, WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ileum. WB800-KR32 markedly changed the richness estimators (Ace and Chao) of gut microbiota and increased the abundance of Eubacterium_rectale_ATCC_33656 in the feces. The results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway, providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.

Rice bran oil supplementation protects swine weanlings against diarrhea and lipopolysaccharide challenge

Early weaned piglets suffer from oxidative stress and enteral infection, which usually results in gut microbial dysbiosis, serve diarrhea, and even death. Rice bran oil (RBO), a polyphenol-enriched by-product of rice processing, has been shown to have antioxidant and anti-inflammatory properties both in vivo and in vitro. Here, we ascertained the proper RBO supplementation level, and subsequently determined its effects on lipopolysaccharide (LPS)-induced intestinal dysfunction in weaned piglets. A total of 168 piglets were randomly allocated into four groups of seven replicates (42 piglets each group, (21±1) d of age, body weight (7.60±0.04) kg, and half males and half females) and were given basal diet (Ctrl) or basal diet supplemented with 0.01% (mass fraction) RBO (RBO1), 0.02% RBO (RBO2), or 0.03% RBO (RBO3) for 21 d. Then, seven piglets from the Ctrl and the RBO were treated with LPS (100 μg/kg body weight (BW)) as LPS group and RBO+LPS group, respectively. Meanwhile, seven piglets from the Ctrl were treated with the saline vehicle (Ctrl group). Four hours later, all treated piglets were sacrificed for taking samples of plasma, jejunum tissues, and feces. The results showed that 0.02% was the optimal dose of dietary RBO supplementation based on diarrhea, average daily gain, and average daily feed intake indices in early weaning piglets. Furthermore, RBO protected piglets against LPS-induced jejunal epithelium damage, which was indicated by the increases in villus height, villus height/crypt depth ratio, and Claudin-1 levels, as well as a decreased level of jejunal epithelium apoptosis. RBO also improved the antioxidant ability of LPS-challenged piglets, which was indicated by the elevated concentrations of catalase and superoxide dismutase, and increased total antioxidant capacity, as well as the decreased concentrations of diamine oxidase and malondialdehyde in plasma. Meanwhile, RBO improved the immune function of LPS-challenged weaned piglets, which was indicated by elevated immunoglobulin A (IgA), IgM, β‍‍-defensin-1, and lysozyme levels in the plasma. In addition, RBO supplementation improved the LPS challenge-induced dysbiosis of gut microbiota. Particularly, the indices of antioxidant capacity, intestinal damage, and immunity were significantly associated with the RBO-regulated gut microbiota. These findings suggested that 0.02% RBO is a suitable dose to protect against LPS-induced intestinal damage, oxidative stress, and jejunal microbiota dysbiosis in early weaned piglets.

Dietary lactate supplementation can alleviate DSS-induced colitis in piglets

Colitis is a common and complex intestinal inflammatory disease in which lactate, a metabolite of anaerobic glycolysis, plays a crucial role. Our study aimed to investigate the alleviated effect of lactate in colitis, and to provide a nutritional measure to alleviate colitis injury. The variations in colonic lactate in piglets with DSS-induced colitis were investigated in Experiment 1 (Exp.1). Thirty weaned pigs were allotted into three groups and sampled at different stages of DSS-induced colitis (days 0, 5, and 7). The colonic level of lactate and interleukin 10 (IL-10) was significantly decreased on day 5 when compared to day 0. Colonic lactate, IL-10, and G protein receptor 81 (GPR81) levels were significantly increased on day 7 when compared to day 5. Sixty weaned piglets were assigned to control (basal diet), DSS (basal diet with DSS gavage), or lactate (2% lactate supplementation diet with DSS gavage) groups to investigate the effects of lactate on DSS-induced colitis in Experiment 2 (Exp.2). Lactate reduced the disease activity index (DAI), DSS-induced impairment of colonic structure in response to the critical inflammatory cytokines interleukin 1β (IL-1β) and interleukin 18 (IL-18) when compared with the DSS group. Furthermore, GPR-81 levels, colonic M2 macrophages, and IL-10 levels, the colonic antioxidant capacity, colonic butyrate levels were increased, and eventually improved growth performance post-colitis. The results of this study show that lactate was decreased at the peak of colitis, accumulated in subsidized colitis. Furthermore, dietary lactate supplementation helped to alleviate DSS-induced colitis injury.

Effects of alkaline mineral complex water supplementation on growth performance, inflammatory response and intestinal barrier function in weaned piglets

The purpose of the present study was to investigate the effects of drinking water alkaline mineral complex (AMC) supplementation on growth performance, intestinal morphology, inflammatory response, immunity, antioxidant defense system, and barrier functions in weaned piglets. In a 15-day trial, 240 weaned piglets (9.35 ± 0.86 kg) at 28 days of age (large white × landrace × Duroc) were randomly divided into two groups: the control (Con) group and the AMC group. Drinking water AMC supplementation improved (P<0.01) final body weight (BW) and average daily gain (ADG) in weaned piglets compared to the Con group. Importantly, AMC reduced (P<0.01) the feed-to-gain (F:G) ratio. AMC water improved the physical health conditions of piglets under weaning stress, as reflected by the decreased (P<0.05) hair score and conjunctival score. Moreover, there was no significant (P>0.05) difference in relatively small intestinal length, organ (liver, spleen and kidney) indices, or gastrointestinal pH value in weaned piglets between the two groups. Of note, AMC significantly promoted the microvilli numbers in the small intestine and effectively ameliorated the gut morphology damage induced by weaning stress, as evidenced by the increased (P<0.05) villous height (VH) and ratio of VH to crypt depth. Additionally, AMC lessened the levels of lipopolysaccharide (LPS, P<0.01) and the contents of IL1β (P<0.05), and TNF-α (P<0.05) in the weaned piglet small intestine. Conversely, the gut immune barrier marker, secretory immunoglobulin A (sIgA) levels in serum and small intestine mucosa were elevated after AMC water treatment (P<0.01). Furthermore, AMC elevated the antioxidant mRNA levels of (P<0.05) SOD 1-2, (P<0.01) CAT, and (P<0.01) GPX 1-2 in the small intestine. Likewise, the mRNA levels of the small intestine tight junction factors Occludin (P<0.01), ZO-1 (P<0.05), Claudin 2 (P<0.01) and Claudin 5 (P<0.01) in the AMC treatment group were notably higher than those in the Con group. In conclusion, drinking water AMC supplementation has an accelerative effect on growth performance by elevating gut health by improving intestinal morphology, the inflammatory response, the antioxidant defense system, and barrier function in weaned piglets.

Ferric citrate is a safe and digestible source of iron in broilers and piglets

Background

Iron (Fe) is traditionally supplemented in poultry and swine diets using inorganic forms (e.g. sulfates, oxides). However, research suggests that organic sources are more beneficial due to greater bioavailability. In this paper, we present results from four studies aimed at assessing ferric citrate (CI-FER™, Akeso Biomedical Inc., Burlington, MA, USA) as a safe and effective source of Fe for broilers and piglets.

Methods

A total of four studies were performed in Germany following standard farming practices for each species. One study in day-old broiler chicks and one study in weaned piglets were designed as target animal safety studies where animals were randomly allocated to one of three treatment groups: a negative control group, the proposed dose group and a multifold dose group. Broilers and pigs were fed the experimental diets for 35 and 42 days, respectively. In each study, average daily feed intake, average daily weight gain and feed conversion ratio were measured, and blood samples were taken at study end for routine biochemistry and haematology. The other two studies were designed to evaluate different sources of dietary Fe for weaned piglets bred and managed under standard farm conditions. All piglets received routine Fe injections (200 mg Fe dextran, intramuscular) on day 3 of age, as well as the experimental diets for 42 days. In both studies, performance parameters were measured. In one study, Fe digestibility and serum Fe, superoxide dismutase and haptoglobin were also measured. In all studies, the general health status of the animals was monitored daily and all culls and mortality recorded. Each study followed a complete randomised block design.

Results

In broilers, ferric citrate was well tolerated up to 2,000 mg/kg feed (×10 the recommended inclusion rate) and no adverse effects on growth, blood parameters or mortality were observed. In piglets, ferric citrate was well tolerated up to 5,000 mg/kg feed (×10 the recommended inclusion rate) with no adverse effects on growth, blood parameters or mortality. In addition, piglets fed ferric citrate performed significantly better than animals fed the negative control diet (containing only endogenous Fe) and those fed inorganic forms of Fe. Moreover, piglets fed ferric citrate demonstrated improved Fe digestibility and improved oxidative status. Altogether, these findings show that ferric citrate is a safe and easily digestible source of dietary Fe for broilers and piglets.

Response of the nuclear xenobiotic receptors to alleviate glyphosate-based herbicide-induced nephrotoxicity in weaned piglets

Glyphosate-based herbicides (GBHs) are widely used worldwide. Glyphosate (GLP) is the main active component of GBHs. The presence of GBH residues in the environment has led to the exposure of animals to GBHs, but the mechanisms of GBH-induced nephrotoxicity are not clear. This study investigated the effects of GBHs on piglet kidneys. Twenty-eight healthy female hybrid weaned piglets (Duroc × Landrace × Yorkshire) with an average weight of 12.24 ± 0.61 kg were randomly divided into four treatment groups (n=7 piglets/group) that were supplemented with Roundup® (equivalent to GLP concentrations of 0, 10, 20, and 40 mg/kg) for a 35-day feeding trial. The results showed that the kidneys in the 40-mg/kg GLP group suffered slight damage. Roundup® significantly decreased the activity of catalase (CAT) (P=0.005) and increased the activity of superoxide dismutase (SOD) (P=0.029). Roundup® increased the level of cystatin-C (Cys-C) in the plasma (linear, P=0.002 and quadratic, P=0.015). The levels of neutrophil gelatinase-associated lipocalin (NGAL) in plasma increased linearly (P=0.007) and quadratically (P=0.003) as the dose of GLP increased. The mRNA expression of intercellular cell adhesion molecule-1 (ICAM-1) in the 20-mg/kg GLP group was increased significantly (P<0.05). There was a significant increase in the mRNA levels of pregnenolone X receptor (PXR), constitutive androstane receptor (CAR), and uridine diphosphate glucuronosyltransferase 1A3 (UGT1A3) (P<0.05). Our findings found that kidney nuclear xenobiotic receptors (NXRs) may play an important role in defense against GBHs.

Dietary ferulic acid supplementation improves intestinal antioxidant capacity and intestinal barrier function in weaned piglets

This study was conducted to explore the effects of dietary ferulic acid (FA) supplementation on intestinal antioxidant capacity and intestinal barrier function in weaned piglets. Eighteen 21-day-old castrated male DLY (Duroc × Landrace × Yorkshire) weaned piglets were randomly divided into control, 0.05% FA, and 0.45% FA groups, respectively. The experiment lasted for 5 weeks. The results showed that dietary 0.05 and 0.45% FA supplementation significantly increased catalase activity (p < 0.001), the protein levels of nuclear factor E2-related factor 2 (Nrf2) and NAD(P)H quinone dehydrogenase 1 (p < 0.05), and the mRNA levels of superoxide dismutase 1, glutathione reductase and Nrf2 (p < 0.05) in jejunum when compared with the control group. Dietary 0.05% FA supplementation also increased the mRNA level of glutathione S-transferase (p < 0.05) in jejunum. Meanwhile, Dietary 0.05 and 0.45% FA supplementation significantly increased the protein expression of zonula occludens 1 (ZO-1) (p < 0.05), and dietary supplementation of 0.05% FA increased the mRNA levels of ZO-1, zonula occludens 2, mucin 1, mucin 2, occluding, and claudin-1 (p < 0.05) in jejunum. Together, our data suggest that dietary 0.05% FA supplementation improves the intestinal antioxidant capacity and intestinal barrier function of weaned piglets.

Berberine improves intestinal barrier function and reduces inflammation, immunosuppression, and oxidative stress by regulating the NF-κB/MAPK signaling pathway in deoxynivalenol-challenged piglets

The aim of this study was to evaluate the effect of berberine (BBR) on the intestinal health of piglets exposed to deoxynivalenol (DON). A total of 180 weaned piglets were randomly allotted to 1 of 3 treatment groups with 10 replication pens per treatment and 6 piglets per pen. The treatments were basal diet, basal diet +4 mg/kg DON, and basal diet +4 mg/kg DON +40 mg/kg BBR. The experiment lasted for 21 d. BBR improved the growth performance of DON-challenged piglets. BBR could inhibit DON-induced intestinal injury by increasing the expression of serum antioxidant enzymes and T cell surface antigens and reducing the release of proinflammatory cytokines in the small intestine. BBR significantly increased the protein expression levels of zonula occludens 1 (ZO-1), Occludin and Claudin-1 in the ileal and jejunal mucosa and increased the morphological parameters of the jejunum. Moreover, we found that BBR significantly reduced the DON-induced gene and protein expression levels of ERK, JNK, and NF-κB in the jejunum and ileum. In conclusion, BBR can regulate DON-induced intestinal injury, immunosuppression and oxidative stress by regulating the NF-κB and MAPK signaling pathways and ultimately maintain the intestinal health of piglets.

Dietary supplementation of fructooligosaccharides alleviates enterotoxigenic E. coli-induced disruption of intestinal epithelium in a weaned piglet model

Diarrhea caused by pathogens such as enterotoxigenic E. coli (ETEC) is a serious threat to the health of young animals and human infants. Here, we investigated the protective effect of fructooligosaccharides (FOS) on the intestinal epithelium with ETEC-challenge in a weaned piglet model. Twenty-four weaned piglets were randomly divided into three groups: (1) non-ETEC-challenged control (CON), (2) ETEC-challenged control (ECON), and (3) ETEC challenge + 2.5 g/kg FOS (EFOS). On day 19, the CON pigs were orally infused with sterile culture, while the ECON and EFOS pigs were orally infused with active ETEC (2.5 × 109 colony-forming units). On day 21, pigs were slaughtered to collect venous blood and small intestine. Result showed that the pre-treatment of FOS improved the antioxidant capacity and the integrity of intestinal barrier in the ETEC-challenged pigs without affecting their growth performance. Specifically, comparing with ECON pigs, the level of GSH-Px (glutathione peroxidase) and CAT (catalase) in the plasma and intestinal mucosa of EFOS pigs was increased (P<0.05), and the intestinal barrier marked by ZO-1 and plasmatic DAO was also improved in EFOS pigs. A lower level (P<0.05) of inflammatory cytokines in the intestinal mucosa of EFOS pigs might be involved in the inhibition of TLR4/MYD88/NF-κB pathway. The apoptosis of jejunal cells in EFOS pigs was also lower than that in ECON pigs (P<0.05). Our findings provide convincing evidence of possible prebiotic and protective effect of FOS on the maintenance of intestinal epithelial function under the attack of pathogens.

Comparative effects of enzymatic soybean, fish meal and milk powder in diets on growth performance, immunological parameters, SCFAs production and gut microbiome of weaned piglets

Background

The objective of this study was to evaluate the replacement effects of milk powder (MK) and fish meal (FM) by enzymatic soybean (ESB) in diets on growth performance, immunological parameters, SCFAs production and gut microbiome of weaned piglets.

Methods

A total of 128 piglets with initial body weight at 6.95 ± 0.46 kg, were randomly assigned into 4 dietary treatments with 8 replicates per treatment and 4 piglets per replicate for a period of 14 d. Piglets were offered iso-nitrogenous and iso-energetic diets as follows: CON diet with MK and FM as high quality protein sources, ESB plus FM diet with ESB replacing MK, ESB plus MK diet with ESB replacing FM, and ESB diet with ESB replacing both MK and FM.

Results

No significant differences were observed in growth performance among all treatments (P > 0.05). However, piglets fed ESB plus FM or ESB diet had increased diarrhea index (P<0.01), and lower digestibility of dry matter (DM), gross energy (GE) or crude protein (CP), relative to piglets fed CON diet (P <  0.01). Moreover, the inclusion of ESB in diet markedly decreased the plasma concentration of HPT and fecal concentration of butyric acid (BA) (P<0.01). The High-throughput sequencing of 16S rRNA gene V3−V4 region of gut microbiome revealed that the inclusion of ESB in diet increased the alpha diversity, and the linear discriminant analysis effect size (LEfSe) showed that piglets fed with ESB plus FM or ESB diet contained more gut pathogenic bacteria, such as g_Peptococcus, g_Veillonella and g_Helicobacter.

Conclusion

The inclusion of ESB in diet did not markedly affect growth performance of piglets, but the replacement of MK or both MK and FM by ESB increased diarrhea index, which could be associated with lower nutrients digestibility and more gut pathogenic bacteria. However, piglets fed diet using ESB to replace FM did not markedly affect gut health-related parameters, indicating the potential for replacing FM with ESB in weaning diet.

Nano chitosan-zinc complex improves the growth performance and antioxidant capacity of the small intestine in weaned piglets

The present study was conducted to test the hypothesis that dietary supplementation with a nano chitosan-zinc complex (CP-Zn, 100 mg/kg Zn) could alleviate weaning stress in piglets challenged with enterotoxigenic Escherichia coli K88 by improving growth performance and intestinal antioxidant capacity. The in vivo effects of CP-Zn on growth performance variables (including gastrointestinal digestion and absorption functions and the levels of key proteins related to muscle growth) and the antioxidant capacity of the small intestine (SI) were evaluated in seventy-two weaned piglets. The porcine jejunal epithelial cell line IPEC-J2 was used to further investigate the antioxidant mechanism of CP-Zn in vitro. The results showed that CP-Zn supplementation increased the jejunal villus height and decreased the diarrhoea rate in weaned piglets. CP-Zn supplementation also improved growth performance (average daily gain and average daily feed intake), increased the activity of carbohydrate digestion-related enzymes (amylase, maltase, sucrase and lactase) and the mRNA expression levels of nutrient transporters (Na+-dependent glucose transporter 1, glucose transporter type 2, peptide transporter 1 and excitatory amino acid carrier 1) in the jejunum and up-regulated the expression levels of mammalian target of rapamycin (mTOR) pathway-related proteins (insulin receptor substrate 1, phospho-mTOR and phospho-p70S6K) in muscle. In addition, CP-Zn supplementation increased glutathione content, enhanced total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-px) activity, and reduced malondialdehyde (MDA) content in the jejunum. Furthermore, CP-Zn decreased the content of MDA and reactive oxygen species, enhanced the activity of T-SOD and GSH-px and up-regulated the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) pathway-related proteins (Nrf2, NAD(P)H:quinone oxidoreductase 1 and haeme oxygenase 1) in lipopolysaccharide-stimulated IPEC-J2 cells. Collectively, these findings indicate that CP-Zn supplementation can improve growth performance and the antioxidant capacity of the SI in piglets, thus alleviating weaning stress.

Chitosan-chelated zinc modulates ileal microbiota, ileal microbial metabolites, and intestinal function in weaned piglets challenged with Escherichia coli K88

This study was to investigate the effects of chitosan-chelated zinc on ileal microbiota, inflammatory response, and barrier function in weaned piglets challenged with Escherichia coli K88. Piglets of the chitosan-chelated zinc treatment (Cs-Zn; 100 mg zinc + 766 mg chitosan/kg basal diet, from chitosan-chelated zinc) and the chitosan treatment (CS, 766 mg chitosan/kg basal diet) had significantly increased ileal villus height and the ratio of villi height to crypt depth. CS-Zn group piglets had a higher abundance of Lactobacillus in the ileal digesta, while the abundance of Streptococcus, Escherichia shigella, Actinobacillus, and Clostridium sensu stricto 6 was significantly decreased. The concentrations of propionate, butyrate, and lactate in the CS-Zn group piglets were significantly increased, while the pH value was significantly decreased. Furthermore, the concentrations of IL-1β, TNF-α, MPO, and INF-γ in the ileal mucosa of the CS-Zn and the H-ZnO group (pharmacological dose of 1600 mg Zn/kg basal diet, from ZnO) were significantly lower than those of the control group fed with basal diet, and the mRNA expression of TLR4, MyD88, and NF-κB of the CS-Zn group was also reduced. In addition, the mRNA expression of IGF-1 was increased, the protein expression of occludin and claudin-1 was enhanced, while the mRNA expression of caspase 3 and caspase 8 was decreased in the CS-Zn group. These results suggest CS-Zn treatment could help modulate the composition of ileal microbiota, attenuate inflammatory response, and maintain the intestinal function in weaned piglets challenged with Escherichia coli K88. KEY POINTS: • Chitosan-chelated zinc significantly modulated ileal microbiota. • Chitosan-chelated zinc can improve ileal health. • The ileal microbiota plays an important role in host health.