Weaning Piglets Research Articles

Influence of host-specific and locally isolated multi-strain probiotics on piglet performance, mortality, inflammatory response, and gut microbiome.

This study aimed to assess the impact of host-specific and locally isolated multi-strain probiotics on piglet performance, mortality, inflammatory responses, and gut microbiome. A total of 52 piglet litters-34 from Landrace sows and 18 from Large White sows-were allocated to two groups: a control group and a multi-strain probiotic group. The probiotic group comprised seven strains of lactic acid bacteria (MLAB): Lactobacillus brevis, Lactobacillus reuteri, Lactobacillus paraplantarum, Lactococcus lactis, Lactobacillus pentosus, Weissella cibaria, and Pediococcus pentosaceus. Each strain was included in equal concentrations, resulting in a final liquid mixture containing 109 CFU/mL. The MLAB group received the probiotics orally starting from 7 days of age until weaning at four weeks. Following weaning, supplementation continued via feed spraying for an additional four weeks. MLAB supplementation did not significantly affect piglet performance but showed a trend towards reducing the mortality rate (p = 0.06). It influenced the inflammatory response by upregulating the expression of anti-inflammatory cytokines interleukin (IL)-4 and IL-10 (p<0.05). Microbial community analysis indicated that MLAB supplementation increased both microbial diversity (Simpson index: p = 0.06) and species richness (Chao1 index: p = 0.02). Piglets receiving MLAB had a significantly higher abundance of the phylum Firmicutes (p<0.01) compared to the control group, while the abundance of the phylum Bacteroidota was markedly reduced (p<0.01). In addition, the relative abundance of the bacterial genera Prevotellaceae_NK3B31 (p<0.01) and Chlamydia (p = 0.03) was lower in the MLAB group. Overall, these results suggest that while MLAB supplementation does not directly improve piglet growth performance, it has the potential to improve immune function and promote a healthier gut microbiota in weaning piglets, which could ultimately reduce mortality rates.

Chinese Herbal Medicines as Natural Alternative Products to Antibiotics in Weaned Piglets through Intestinal Microbiota Regulation.

During the growth process of weaned piglets, digestive problems such as gastrointestinal disorders and diarrhea are common. Farmers usually use antibiotics to help piglets grow smoothly. However, the overuse of antibiotics can lead to antibiotic resistance issues. Therefore, this study chose to use plant extracts as feed additives to explore their potential as alternatives to antibiotics. Additionally, Tilmicosin was used as the antibiotic because it is widely used in treating respiratory infections in piglets. Since traditional Chinese medicine often uses natural products, we selected Guizhi Li-Zhong (GLZ) extract as an alternative to antibiotics. The experiment involved 126 piglets, each 4 weeks old, which were randomly assigned to one of four groups: the sham group (basal diet without supplements, 10.3 ± 0.4 kg, n = 31), the low-dose GLZ group (basal diet with 0.05% GLZ, 10.9 ± 0.4 kg, n = 32), the regular-dose GLZ group (basal diet with 0.2% GLZ, 10.6 ± 0.4 kg, n = 32), and the regular-dose Tilmicosin antibiotic group (basal diet with 0.2% Tilmicosin, 10.2 ± 0.3 kg, n = 31). We recorded and compared the survival rate, growth rate, feed conversion ratio, and diarrhea incidence among four groups of weaned piglets from the 4th to the 10th weeks of age. Then, we examined the oxidative stress, inflammation, and apoptosis in small intestine tissue (jejunum and ileum) through immunohistochemistry and Western blot and compared the gut microbiota in large intestine tissue (colon and rectum) through a next-generation sequencing (NGS) analysis. Our results showed that weaned piglets supplemented with 0.05% and 0.2% GLZ had better survival rates, growth rates (p < 0.01), and feed conversion ratios (p < 0.01) compared to those receiving sham treatment. Even weaned piglets supplemented with 0.2% GLZ performed better than those supplemented with 0.2% Tilmicosin antibiotics (p < 0.05). Furthermore, the incidence of diarrhea and small intestine injury (indicated by oxidative stress-, inflammation-, and apoptosis-related proteins) in piglets supplemented with 0.05% and 0.2% GLZ was lower than in piglets receiving sham treatment (p < 0.05). Even piglets supplemented with 0.2% GLZ had less injury than those supplemented with 0.2% Tilmicosin antibiotics (p < 0.05). The NGS results further showed that GLZ treatment significantly improved beneficial bacteria in weaned piglets (p < 0.05), while antibiotic treatment reduced beneficial bacteria (p < 0.05). In summary, we recommend adding GLZ to the feed as an alternative to antibiotics. This not only effectively reduces intestinal damage but also improves the gut microbiota, thereby promoting the growth of weaning piglets.

Effects of microbe-derived antioxidants on growth performance, hepatic oxidative stress, mitochondrial function and cell apoptosis in weaning piglets

BackgroundWeaning causes redox dyshomeostasis in piglets, which leads to hepatic oxidative damage. Microbe-derived antioxidants (MA) have great potential for anti-oxidation. This study aimed to investigate changes in hepatic redox system, mitochondrial function and apoptosis after weaning, and effects of MA on growth performance and liver health in weaning piglets.MethodsThis study consisted of 2 experiments. In the both experiments, piglets were weaned at 21 days of age. In Exp. 1, at 21 (W0), 22 (W1), 25 (W4), 28 (W7), and 35 (W14) days of age, 6 piglets were slaughtered at each timepoint. In Exp. 2, piglets were divided into 2 groups: one received MA gavage (MA) and the other received saline gavage (CON). At 25 days of age, 6 piglets from each group were sacrificed.ResultsIn Exp. 1, weaning caused growth inhibition and liver developmental retardation from W0 to W4. The mRNA sequencing between W0 and W4 revealed that pathways related to “regulation of apoptotic process” and “reactive oxygen species metabolic process” were enriched. Further study showed that weaning led to higher hepatic content of reactive oxygen species (ROS), H2O2 and O2−. Weaning enhanced mitochondrial fission and suppressed their fusion, activated mitophagy, thus triggering cell apoptosis. In Exp. 2, MA improved growth performance of piglets with higher average daily gain (ADG) and average daily feed intake (ADFI). The hepatic ROS, as well as products of oxidative damage malonaldehyde (MDA) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in the MA group decreased significantly than that of the CON group. The MA elevated mitochondrial membrane potential, increased activity of mitochondrial respiratory chain complexes (MRC) I and IV, enhanced mitochondrial fusion and reduced mitophagy, thus decreasing cell apoptosis.ConclusionsThe present study showed that MA improved the growth performance of weaning piglets and reversed weaning-induced oxidative damage, mitochondrial dysfunction, and apoptosis. Our results suggested that MA had promising prospects for maintaining liver health in weaning piglets and provided a reference for studies of liver diseases in humans.Graphical

Fermented Rapeseed Meal as a Dietary Intervention to Improve Mineral Utilization and Bone Health in Weaned Piglets.

This study examined the effects of incorporating fermented rapeseed meal (FRSM) into the diet of newly weaned piglets on mineral digestibility and bone health. Experimental diets containing varying levels of FRSM (8%, 12%, 15%, and 25%) were introduced to the piglets at 18 days of age, prior to weaning at 28 days. These diets were continued until the piglets were euthanized at 42 days of age. Mineral absorption was assessed using the apparent total tract digestibility (ATTD) method and blood plasma element analysis, while bone mineral content and mechanical properties were evaluated through densitometry and three-point bending tests. The results showed that intermediate levels of FRSM (12-15%) significantly enhanced the digestibility of key minerals, including phosphorus, calcium, magnesium, copper, zinc, and iron. This improvement was linked to increased femoral mineral content and bone stiffness, as well as a higher yield point, likely due to enhanced collagen synthesis. Additionally, there was an increase in bone fracture load and fracture stress, potentially due to changes in the organization of the bone mineral phase, as no changes in bone mid-shaft mineral density or geometry were observed. These findings suggest FRSM as a promising dietary component for improving mineral bioavailability and bone health in piglets.

Effects of Microencapsulated Essential Oils on Growth and Intestinal Health in Weaned Piglets.

The study investigated the effects of microencapsulated essential oils (MEO) on the growth performance, diarrhea, and intestinal microenvironment of weaned piglets. The 120 thirty-day-old weaned piglets (Duroc × Landrace × Yorkshire, 8.15 ± 0.07 kg) were randomly divided into four groups and were fed with a basal diet (CON) or CON diet containing 300 (L-MEO), 500 (M-MEO), and 700 (H-MEO) mg/kg MEO, respectively, and data related to performance were measured. The results revealed that MEO supplementation increased the ADG and ADFI in weaned piglets (p < 0.05) compared with CON, and reduced diarrhea rates in nursery pigs (p < 0.05). MEO supplementation significantly increased the duodenum's V:C ratio and the jejunal villi height of weaned piglets (p < 0.05). The addition of MEO significantly increased the T-AOC activity in the jejunum of piglets (p < 0.05), but only L-MEO decreased the MDA concentration (p < 0.01). H-MEO group significantly increases the content of isobutyric acid (p < 0.05) in the piglet colon, but it does not affect the content of other acids. In addition, MEO supplementation improved appetite in the nursery and increased the diversity and abundance of beneficial bacteria in the intestinal microbiome. In conclusion, these findings indicated that MEO supplementation improves growth and intestinal health in weaned piglets.

Chlorogenic Acid Enhances the Intestinal Health of Weaned Piglets by Inhibiting the TLR4/NF-κB Pathway and Activating the Nrf2 Pathway.

Chlorogenic acid (CGA) is a natural polyphenol with potent antioxidant and anti-inflammatory activities. However, the exact role of it in regulating intestinal health under oxidative stress is not fully understood. This study aims to investigate the effects of dietary CGA supplementation on the intestinal health of weaned piglets under oxidative stress, and to explore its regulatory mechanism. Twenty-four piglets were randomly divided into two groups and fed either a basal diet (CON) or a basal diet supplemented with 200 mg/kg CGA (CGA). CGA reduced the diarrhea rate, increased the villus height in the jejunum, and decreased the crypt depth in the duodenum, jejunum, and ileum of the weaned piglets (p < 0.05). Moreover, CGA increased the protein abundance of Claudin-1, Occludin, and zonula occludens (ZO)-1 in the jejunum and ileum (p < 0.05). In addition, CGA increased the mRNA expression of pBD2 in the jejunum, and pBD1 and pBD2 in the ileum (p < 0.05). The results of 16S rRNA sequencing showed that CGA altered the ileal microbiota composition and increased the relative abundance of Lactobacillus reuteri and Lactobacillus pontis (p < 0.05). Consistently, the findings suggested that the enhancement of the intestinal barrier in piglets was associated with increased concentrations of T-AOC, IL-22, and sIgA in the serum and T-AOC, T-SOD, and sIgA in the jejunum, as well as T-AOC and CAT in the ileum caused by CGA (p < 0.05). Meanwhile, CGA decreased the concentrations of MDA, IL-1β, IL-6, and TNF-α in the serum and jejunum and IL-1β and IL-6 in the ileum (p < 0.05). Importantly, this study found that CGA alleviated intestinal inflammation and oxidative stress in the piglets by inhibiting the TLR4/NF-κB signaling pathway and activating the Nrf2 signaling pathway. These findings showed that CGA enhances the intestinal health of weaned piglets by inhibiting the TLR4/NF-κB pathway and activating the Nrf2 pathway.

Retrospective Analyses of Porcine Circovirus Type 3 (PCV-3) in Switzerland.

Porcine circovirus 3 (PCV-3) has emerged as a significant pathogen affecting global swine populations, yet its epidemiology and clinical implications remain incompletely understood. This retrospective study aimed to investigate the prevalence and histopathological features of PCV-3 infection in pigs from Switzerland, focusing on archival cases of suckling and weaner piglets presenting with suggestive lesions. An in-house qPCR assay was developed for detecting PCV-3 in frozen and formalin-fixed paraffin-embedded tissues, enhancing the national diagnostic capabilities. Histopathological reassessment identified PCV-3 systemic disease (PCV-3-SD) compatible lesions in 19 (6%) of archival cases, with 47% testing positive by qPCR across various organs. Notably, vascular lesions predominated, particularly in mesenteric arteries, heart, and kidneys. The study confirms the presence of PCV-3 in Switzerland since at least 2020, marking the first documented cases within the Swiss swine population. Despite challenges in in situ hybridization validation due to prolonged formalin fixation, the findings indicate viral systemic dissemination. These results contribute to the understanding of PCV-3 epidemiology in Swiss pigs, emphasizing the need for continued surveillance and further research on its clinical implications and interaction with host factors. Our study underscores the utility and limitations of molecular techniques in confirming PCV-3 infections.

Terminalia Chebula Extract Replacing Zinc Oxide Enhances Antioxidant and Anti-Inflammatory Capabilities, Improves Growth Performance, and Promotes Intestinal Health in Weaned Piglets.

This study aimed to assess the effects of substituting zinc oxide with terminalia chebula extract (TCE) on growth performance, antioxidant capacity, immune function, and intestinal health in weaned pigs. Initially, 72 weaned Duroc × Landrace × Large White piglets, 28 days old with an initial weight of 7.43 ± 0.14 kg, equally divided by gender, were randomly assigned into three groups, with six replicates and four piglets per replicate. They were fed a basal diet (CON group), a diet containing 2 g/kg zinc oxide (ZnO group), or 2 g/kg TCE (TCE group) for a duration of 28 days. Subsequently, to further confirm the most appropriate levels of TCE in piglets, 96 piglets of the same breeds and age, with an initial weight of 7.42 ± 0.12 kg, also equally divided by gender, were randomly assigned into four groups, each with six replicates and four piglets per replicate, and fed a basal diet (CON group), or diets supplemented with 1 g/kg TCE (LTCE group), 2 g/kg TCE (MTCE group), or 4 g/kg TCE (HTCE group) for a duration of 28 days. The results demonstrated that both TCE and ZnO reduced diarrhea rates (p = 0.001) and enhanced average daily gain (ADG) (p = 0.014) compared to the control group. TCE at 1 g/kg and 4 g/kg reduced the feed to gain ratio (p = 0.050). Dietary supplementing with TCE and ZnO increased serum total antioxidant capacity (T-AOC) (p = 0.020). Various doses of TCE also increased jejunal IgA (p = 0.000) levels and IL-10 expression (p = 0.004), and decreased the levels of TNF-α in both serum (p = 0.043) and jejunal mucosa (p = 0.000). Notably, TCE reduced the crypt depth (CD) of the duodenal (p = 0.007) and increased the villus height (VH) of the ileal (p = 0.045), and with increased dosage, there was a rise in the villus height to crypt depth ratio (VH:CD) in the duodenum (p = 0.000) and jejunum (p = 0.001). Higher abundances of Lactobacillaceae (p = 0.000) and lower levels of Streptococcaceae (p = 0.000) and Peptostreptococcaceae (p = 0.035) in cecal contents were fed the ZnO and TCE pigs compared with CON pigs. Therefore, TCE was firstly presented as being able to replace zinc oxide, improve intestinal morphology, and enhance antioxidant and immune functions, thus safeguarding intestinal mucosal health and promoting piglet growth.

Protective Effects of Tea Tree Oil on Inflammatory Injury of Porcine Intestinal Epithelial Cells Induced by Lipopolysaccharide In Vitro.

Tea tree oil (TTO) improves the intestinal mucosal immunity of weaning piglets, but its underlying mechanism is not clear. We hypothesized that TTO may alleviate inflammatory injury by regulating the function of intestinal epithelial cells. Ileum epithelial cells (IPI-2I) were chosen and an inflammatory injury cell model was generated. The cell viability, cytokine secretion, and gene expression of TLR4 and NF-κB were measured to further evaluate the effects of TTO on the inflammatory injury in immune-stressed cells. The results showed that lipopolysaccharide (LPS; content: ≥30 μg/mL; time: 3 h, 6 h, or 9 h) decreased cell viability (p < 0.01), and 50 μg/mL LPS stimulated for 6 h resulted in an increased secretion of proinflammatory cytokines and a dramatically decreased secretion of anti-inflammatory cytokines (p < 0.05) in IPI-2I cells. Concentrations of 0-0.05% of TTO improved cell viability, while the 0.03% TTO treatment resulted in the highest cell viability and alleviated LPS-induced cell death (p < 0.01). In addition, 0.03% TTO alleviated the LPS-induced increase in the gene expression of IL-1β, TNFα, and IFNγ, as well as the decrease in the expression of IL-10 in IPI-2I cells (p < 0.05). LPS also upregulated the gene expression of TLR4 and NF-κB (p < 0.05); while TTO supplementation alleviated this effect (p < 0.05), 0.03% and 0.05% TTO supplementation had greater effects (p < 0.05). In conclusion, 50 μg/mL LPS stimulated for 6 h can be used to establish an immune-stressed cell model in IPI-2I cell lines, and 0.03% TTO treatment for 6 h alleviated inflammatory injury in the intestinal epithelial cells of pigs.

Effect of saccharin (sweetener) supplementation on growth performance, nutrient digestibility, fecal microbial, and fecal score in weaning piglets

Effect of saccharin (sweetener) supplementation on growth performance, nutrient digestibility, fecal microbial, and fecal score in weaning piglets

Supplementation with L-theanine promotes intestinal antioxidant ability via Nrf2 signaling pathway in weaning piglets and H2O2-induced IPEC-J2 cells

This study aimed to investigate the effect of L-theanine in regulating the intestinal antioxidant of weaned piglets and its underlying mechanism. We found that L-theanine increased the activities of antioxidant enzymes and the level of GSH, while decreased the MDA content of weaned piglet jejunum mucosa and H2O2-induced IPEC-J2 cells. In addition, the mRNA expression of SOD1, SOD2, GPx1, CAT, HO-1 and NQO1 was also significantly increased in jejunum mucosa and H2O2-induced IPEC-J2 cells by L-theanine treatment. Furthermore, L-theanine promoted the nuclear Nrf2 expression and decreased the keap1 expression. However, blocking of Nrf2 signaling by ML385 (the Nrf2 inhibitor) repressed the promoting effects of L-theanine on the activities of antioxidative enzymes and the expression of antioxidant related genes, while increased the MDA content and keap1 expression in IPEC-J2 cells. These data provided the first evidence that L-theanine improved intestinal antioxidant ability of weaned piglets by activating Nrf2 signaling pathway.

The Vehicle of Administration and Prandial State May Reduce the Spectrum of Oral Broad-Spectrum Antibiotics (Oxytetracycline, Fosfomycin and Amoxicillin) Administered to Piglets: A Pharmacokinetic/Pharmacodynamic Approach.

The objective of this study was to assess the impact of the vehicle of administration and the prandial state of post weaning piglets on the indices of therapeutic efficacy for different broad-spectrum antibiotic/pathogen combinations. Pharmacokinetic data were retrieved from previous studies, in which we orally administered oxytetracycline (OTC), fosfomycin (FOS), or amoxicillin (AMX) according to the following treatments: dissolved in soft water to fasted or non-fasted piglets, dissolved in hard water to fasted or non-fasted piglets, and mixed with feed. Minimum inhibitory concentration (MIC) values for susceptible strains of bacteria causing swine diseases were obtained from the database of European Committee on Antimicrobial Susceptibility Testing (EUCAST) for each antibiotic. Pharmacokinetic/pharmacodynamic (PK/PD) indices of therapeutic efficacy-drug exposure over the dosing interval (fAUC/MIC) for OTC and FOS; time that free drug concentration remains above MIC (%fT>MIC) for AMX-were calculated for each antibiotic/pathogen combination under each treatment. After all OTC and in-feed FOS and AMX treatments, the indices of therapeutic efficacy were below the target value for all the study microorganisms. When FOS or AMX were delivered dissolved in soft or hard water, the indices were above the target value over which therapeutic efficacy would be expected for Escherichia coli treated with FOS and, Glaesserella parasuis, Pasteurella multocida, and Actinobacillus pleuropneumoniae treated with AMX. The prandial state of piglets showed no influence on the indices of therapeutic efficacy. Pharmacokinetic profiles of broad-spectrum antibiotics, specifically the ability to achieve target concentrations, may be largely reduced due to drug interactions with components present in feed or water resulting in a discrepancy with PK/PD principles of prudent and responsible use of antibiotics.

Optimal control model for the spread of Streptococcus suis in human population

Streptococcus suis infection is a zoonotic disease that can spread from pigs to humans. The infection can cause permanent deafness in people. Although it is considered as a neglected zoonotic pathogen, the prevalence of this infection has not measurably decreased in recent years. In this research, we proposed mathematical models of S. suis infection in both human and pig populations. Disinfectant sterilization in swine farms and educational campaigns were considered for cooperative control strategies. The aim of this study was to derive an optimal control strategy by using optimal control techniques associated with an existing epidemic model. Equilibrium points and the basic reproduction numbers were analyzed to determine the effect of control parameters in the constant case. For the optimal control problem, we showed numerically that the optimal control functions effectively reduced the number of infectious individuals within a finite time. However, the suggested control functions had more impact on the human group than the swine group. The sensitivity analysis implied that the control of swine population should be focused on the surveillance of weaning piglets.

45. The troubling tandem: Investigating the interaction of isoflavones and zearalenone on weaning piglets

45. The troubling tandem: Investigating the interaction of isoflavones and zearalenone on weaning piglets

57. Impact of zinc and copper intake on their digestibility in weaning piglets, with or without xylanase and protease supplementation

57. Impact of zinc and copper intake on their digestibility in weaning piglets, with or without xylanase and protease supplementation

The vehicle of administration, feed or water, and prandial state influence the oral bioavailability of amoxicillin in piglets.

Feed and water components may interact with drugs and affect their dissolution and bioavailability. The impact of the vehicle of administration (feed and water) and the prandial condition of weaner piglets on amoxicillin´s oral bioavailability was evaluated. First, amoxicillin's in vitro dissolution and stability in purified, soft, and hard water, as well as release kinetics from feed in simulated gastric and intestinal media were assessed. Then, pharmacokinetic parameters and bioavailability were determined in fasted and fed pigs using soft water, hard water, or feed as vehicles of administration following a balanced incomplete block design. Amoxicillin showed similar dissolution profiles in soft and hard water, distinct from the dissolution profile obtained with purified water. Complete dissolution was only achieved in purified water, and merely reached 50% in soft or hard water. Once dissolved, antibiotic concentrations decreased by around 20% after 24h in all solutions. Korsmeyer-Peppas model best described amoxicillin release from feed in simulated gastric and intestinal media. Feed considerably reduced antibiotic dissolution in both simulated media. In vivo, amoxicillin exhibited significantly higher bioavailability when delivered via water to fasted than to fed animals, while in-feed administration yielded the lowest values. All treatments showed a similar rate of drug absorption. In conclusion, we demonstrated that water and feed components, as well as feed present in gastrointestinal tract of piglets decrease amoxicillin´s oral bioavailability. Therefore, the use of oral amoxicillin as a broad-spectrum antibiotic to treat systemic infections in pigs should be thoroughly revised.

ЦИРКОВИРУС-МИКОПЛАЗМЕННАЯ ИНФЕКЦИЯ ПОРОСЯТ В ЭКСПЕРИМЕНТЕ

The aim of the study is to investigate the manifestation of circovirus-mycoplasma infection in piglets both as a mixed infection and as a monoinfection in the experiment. Objectives: to study the interaction of circovirus type 2 with Mycoplasma hyopneumoniae in the body of weaned piglets, as well as the manifestation of monoinfection in piglets during experimental infection; to assess the pathogenicity of PCV2d/M.hyo mixed infection, PCV2d monoinfection and M. hyo monoinfection; to identify the clinical and pathomorphological manifestation of mixed and single circovirus and mycoplasma infection in the experiment. Four groups of 23-day-old piglets (5 heads each) were formed and tested for the absence of pathogens. Experimental group I – mixed circovirus-mycoplasma infection, experimental group II – PCV2d monoinfection, experimental group III – M.hyo monoinfection, group IV – control. After infection, rectal temperature was measured daily and clinical manifestations were observed, nasal swabs were taken to determine the number of copies of M. hyo nucleic acid, blood was taken from each piglet weekly to detect viral nucleic acid and antibodies. All experimental and control piglets were euthanized on the 35th day from the beginning of the experiment. Pathomorphological and pathohistological studies were carried out. The experimental study reveals the synergistic pathogenicity of PCV2d and M. hyo in mixed infection. In experimental infection of weaning piglets with both M. hyo monoinfection and M. hyo/PCV2d mixed infection, it was found that M. hyo nucleic acid was detected in nasal smears in 80 % of animals and in lung tissue in 100 %. The number of copies of the PCV2d circovirus genome in the inguinal lymph node tissue of piglets in the mixed infection group was higher than in the monoinfection group. Circovirus type 2 in piglets can proceed latently, and circovirus-mycoplasma infection can be a complex respiratory disease.

Baicalin-aluminum complex on the regulation of IPEC-1 infected with enterotoxigenic Escherichia coli

Enterotoxigenic Escherichia coli (ETEC) is the main bacterial cause of diarrhea in weaned piglets. Baicalin-aluminum (BA) complex is the main active ingredient of Scutellaria baicalensis Georgi extracted-aluminum complex, which has been used to treat diarrhea in weaning piglets, however the underlying mechanism remains unclear. To investigate the effects of the BA complex on the regulation of porcine intestinal epithelial (IPEC-1) cells infected with ETEC, IPEC-1 cells were incubated with an ETEC bacterial strain at a multiplicity of infection of 1 for 6 h and then treated with different concentrations of the BA complex for 6 h. ETEC infection increased the levels of cAMP and cGMP, upregulated CFTR (cystic fibrosis transmembrane conductance regulator) mRNA, and downregulated NHE4 mRNA in IPEC-1 cells. Treatment with the BA complex inhibited ETEC adhesion and the production of cAMP and cGMP, reduced CFTR mRNA expression, and increased NHE4 mRNA expression. Overall, the BA complex weakened the adhesion of ETEC to IPEC-1 cells, and inhibited cAMP/cGMP-CFTR signaling in IPEC-1 cells.

Microencapsulated essential oils alleviate diarrhea in weaned piglets by modulating the intestinal microbial barrier as well as not inducing antibiotic resistance: a field research.

Microencapsulated essential oils (MEO)have been used as antibiotic alternatives that can be applied to alleviate diarrhea in weaning piglet. We examined a large group of weaned piglets and incorporated essential oil containing thymol (2%), carvacrol (5%) and cinnamaldehyde (3%) in the feed of weaned piglets on an intensive production farm. The piglets were divided into four groups; Control (no additions) and chlortetracycline (Chl), essential oil (EO) and microencapsulated essential oil (MEO) were fed ad libitum over a 28-day trial period. We found MEO significantly reduced the incidence of diarrhea in the piglets that was also accompanied by increased average daily weight gains from days 14-28 (p < 0.05). MEO enhanced the antioxidant capacity in the piglets and serum total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-px) levels were significantly increased (p < 0.05). MEO also significantly reduced expression of genes related to ileal inflammation (IL-6, TNF-α and TGF-β1) (p < 0.05) and significantly (p < 0.05) increased in sIgA antibody levels. MEO influenced the composition of the intestinal microbiome and reduced Bacteroidota (p < 0.05) and thus altered the Firmicutes/Bacteroidota ratio. However, none of the treatments produced significant changes in the most common tetracycline resistance genes (p > 0.05). Metagenomic analysis indicated that MEO impacted DNA expression, virulence factors, antioxidant activity and antimicrobial activity. Metabolomic analysis of the intestinal content also indicated that MEO impacted tyrosine metabolism and primary bile acid biosynthesis suggesting improved intestinal health and nutrient absorption. This study paves the way for further research into the development and optimization of MEO-based interventions aimed at improving piglet health and performance while also providing a reference for reducing reliance on antibiotics in animal agriculture.

46 Efficacy of a biosynthetic 6-phytase depending on basal diet composition in weaning piglets

Abstract A study was conducted to evaluate the efficacy of biosynthetic 6-phytase depending on basal diet composition on growth performance and bone mineralization in weaned piglets. A total of 192 male weaned piglets with initial body weight (BW) of 8.47 ± 0.70 kg (at 33 d of age), distributed in a randomized block design with a 3 x 2 factorial arrangement of treatments. Three basal diet compositions (BD1: adequate in energy and nutrients with phytic P (PP) = 0.23%; BD2 = BD1 minus 70 kcal NE/kg, 0.15% points similarly in digestible P (dig.P) and calcium (Ca) with PP = 0.23%; and BD3 = BD1 minus 70 kcal NE/kg, 0.15% points similarly in dig.P and Ca with PP = 0.29%) and two phytase inclusion (Rovabio PhyPlus; 0 or 1,000 FTU/kg diet) were used in this experiment. The corn-soybean meal-based diets were fed into 2 phases: post-weaning 1 and 2 from 1 to 14 and 15 to 42 d, respectively. Body weight and feed intake were measured at the end of each phase, and average daily gain (ADG), average daily feed intake (ADFI) and feed to gain ratio (F:G) were calculated for the whole experimental period. At the end of the study, all piglets from 16 pens per treatment (n = 32 piglets/treatment) were euthanized and the metacarpi bones were collected for bone ash and P content determinations. There were significant interactions (P &amp;lt; 0.05) between basal diet composition and phytase inclusion on final BW, ADG, F:G, ash and P contents in metacarpal bones of piglets. Compared with unsupplemented diet, the addition of phytase in both nutrient-reduced diets improved final BW, ADG, F:G, ash and P contents in bones, while no improvements (P &amp;gt; 0.05) were observed on these parameters by phytase supplementation in adequate-nutrient diet. There was no significant interaction (P &amp;gt; 0.05) between basal diet composition and phytase inclusion on ADFI. Reduction in nutrients without (BD2) or with increasing dietary PP level (BD3) decreased (P = 0.004) ADFI, compared with adequate-nutrient diet. However, addition of biosynthetic 6-phytase improved (P = 0.03) ADFI by 5.3% compared with unsupplemented diets. The results of the present study highlight that adding biosynthetic 6-phytase to low energy and nutrient diets was more effective compared with the effects in an adequate-nutrient diet in weaned piglets.