Microencapsulated essential oils combined with organic acids improves immune antioxidant capacity and intestinal barrier function as well as modulates the hindgut microbial community in piglets

Effects of Dioscorea oppositifolia L. on growth performance, biochemical indicators, immunity, and intestinal health of weaned piglets

Introduction

Weaning stress syndrome in piglets seriously endangers the healthy development of the breeding industry. Dioscorea oppositifolia L. (Chinese yam, YAM) has activities such as boosting immunity and regulating gastrointestinal function. In order to explore the potential efficacy of YAM on weaned piglets, this study aimed to investigate the effects of growth performance, immune function, intestinal health and intestinal flora composition of weaned piglets.

Methods

Forty-eight 28-day-old weaned piglets were randomly divided into a control group, YAML group and YAMH group, with 0, 1 and 2% YAM added to the basal diet, respectively. During the experiment, the piglets' feed intake was recorded, and blood and fecal samples were collected. After the feeding period, intestinal tissue samples and colon content samples were collected for testing.

Results

The results showed that adding YAM to the diet can lower the incidence of diarrhea in weaned piglets, improve growth performance and nutrient digestibility, and reduce serum enzyme activity alanine aminotransferase (ALT), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C); in addition, YAM can also increase serum immunoglobulins (Ig) and antibody titers, regulate the level of inflammatory factors, and promote the expression of secretory immunoglobulin A (SIgA) protein in the intestine. Furthermore, supplementation with YAM can increase the villus height (VH), the ratio of villus height to crypt depth (V/C), and the expression of Tight junctions (TJs), and also has a positive regulatory effect on the intestinal flora.

Discussion

In summary, YAM alleviates weaning stress syndrome in piglets by promoting growth performance, improving immune function and disease resistance, improving intestinal morphology and mucosal immunity, and regulating the intestinal microbial composition of piglets. This provides a theoretical basis for the development and application of YAM as a new plant-derived feed additive.

Effects of Lactic Acid and Glyceryl Lactate on Growth Performance, Antioxidant Capacity, and Intestinal Health of Piglets

The aim of this study was to evaluate the effects of lactic acid and glyceryl lactate on growth performance, antioxidant capacity, and intestinal health in piglets. This study included 240 castrated male piglets (initial body weight: 7.50 ± 0.54 kg) assigned to four groups: CON (basal diet), LA (basal diet + 0.5% lactic acid), GL (basal diet + 0.5% glyceryl lactate), and LG (basal diet + 0.5% lactic acid + 0.5% glyceryl lactate). Each group had six replicates of 10 piglets. The trial lasted 28 days. Compared with the control group, the GL and LG groups showed enhanced growth performance and reduced diarrhea rate in piglets. The LA and LG groups showed decreased intestinal chyme pH and increased digestive enzyme activities. Moreover, the GL and LG groups displayed elevated jejunal mRNA levels of the tight junction protein occludin and mucin MUC2, enhanced expression levels of Nrf2 signaling pathway genes, increased activities of the antioxidant enzymes GPX and CAT, and reduced MDA content. Acidifier supplementation also modulated cecal bacterial abundance and short-chain fatty acid (SCFA) content. Genera such as Faecalibaculum, Nocardiopsis, Collinsella, CAG269, Allobaculum, and Enterococcus were affected. In conclusion, glyceryl lactate and its combination with lactic acid improved piglet growth performance by enhancing intestinal barrier function, antioxidant capacity, microbial community structure, and SCFA production.

Effects of monoglyceride blend on performance and intestinal health status of piglets fed diets without growth promoters

The study aimed to evaluate the effects of supplementing monoglyceride blend in diets without growth promoters on performance, diarrhea occurrence, blood profile, intestinal morphology and pH, mRNA expression of nutrient transporters, inflammatory markers, antioxidant enzymes, and junction proteins in weaned piglets. Forty piglets were randomly allocated to five groups fed the following diets: control (C), or supplemented with 0.75 g/kg of a blend of fatty acids in powder form (PA), or with 3.00 g/kg of a blend of fatty acids in powder form (HPA), or with 0.50 g/kg of a blend of fatty acids in liquid form (LA), or with 2.00 g/kg of a blend of fatty acids in liquid form (HLA). The LA and PA diets reduced (P < 0.05) the occurrence of diarrhea. The pH of intestinal contents was reduced (P < 0.05) in piglets fed monoglycerides blend. Fecal E. coli count tended (0.05 ≤ P < 0.1) to be reduced in piglets receiving all supplemented diets. LA diet increased (P < 0.05) villus height in the duodenum, while others tended to increase it (0.05 ≤  P < 0.1). In the jejunum, all supplemented diets increased (P < 0.05) the goblet cell proportion. In the ileum, PA diet reduced (P < 0.05) crypt depth and increased (P < 0.05) villus: crypt ratio, and PA, HPA, and HLA diets increased (P < 0.05) goblet cell proportion. In the ileum, HPA and LA diets tended to reduce (0.05 ≤  P < 0.1) crypt depth and Peyer's patch. In the jejunum, LA and HLA diets increased (P < 0.05) the expression of Occludin and HPA increased the expression of Interleukin-10. In conclusion, the supplementation with a monoglyceride blend improves intestinal health and morphology, and local immune response in piglets fed diets without growth promoters.

Therapeutic efficacy of compound organic acids administration on methicillin-resistant Staphylococcus aureus-induced arthritis in broilers

Avian arthritis is a common disease in the poultry industry, and the etiology is complex. Bacterial arthritis is usually caused by Staphylococcus aureus (S. aureus) infection. This study explored the minimum inhibitory concentration (MIC) of different organic acids against S. aureus MRSA85 and found that vanillic acid, suberic acid, itaconic acid, salicylic acid, and other organic acids had significant inhibitory effects on this strain, especially cinnamic acid, which exhibited the best inhibitory effect. The Fractional Inhibitory Concentration Index (FICI) test further revealed the synergistic effect among some compound organic acids, which can significantly enhance the antibacterial efficiency against MRSA85 while reducing the risk of bacterial resistance. Under the low concentrations (1/2 or 1/4 MIC) conditions, the MIC of the compound organic acids against S. aureus remains unchanged, and it can even enhance the sensitivity of antibiotic-resistant S. aureus to Oxacillin. Furthermore, the compound organic acids could effectively promote the recovery of S. aureus-induced arthritis in broiler models, reduce inflammatory responses, and lower down bacterial loads and inflammatory cytokine levels in joints, which indicated that the effects of the Compound 2 is comparable to that of the trimethoprim-sulfamethoxazole group. These results support the potential and application value of organic acids and their compounds, including Compound 1 to 3, as novel antibacterial agents in the treatment of S. aureus infections.

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.

Plant essential oils combined with organic acids restored lipopolysaccharide-induced leaky intestine via gut microbial modulation in weaned piglets

Intestine derived lipopolysaccharide (LPS) is closely related to systemic inflammation and disorders, yet little is known about its roles in the weanling stress of piglets and its potential as a nutritional intervention target. This study aimed to investigate the potential of essential oils (EO) and organic acids (OA) in mitigating weaning stress in piglets by modulating the circulation of intestine derived LPS. Seventy-two weaned piglets at 21 d old with body weight of 8.12 ± 0.168 kg were randomly divided into a control group (CON) and an experimental group, each consisting of six pens with six piglets per pen, and were fed either a basal diet or a basal diet supplemented with 3 kg/t OA + 500 g/t EO (EO + OA). On the 14th day of the feeding trial, 12 weaned piglets were randomly selected from the CON group, and 6 piglets were selected from the experimental group. Based on diet composition and stress treatment, these 18 piglets were divided into the following three groups: 1) CON group. Piglets were fed a basal diet and received an intraperitoneal injection of saline as a control. 2) LPS group. Piglets were fed a basal diet and received an intraperitoneal injection of LPS (100 μg/kg body weight) to induce stress. 3) EO + OA + LPS group. Piglets were fed a basal diet supplemented with EO and OA and received an intraperitoneal injection of LPS (100 μg/kg body weight) to induce stress. The results showed that EO + OA significantly ameliorated the oxidative imbalance and inflammation disorder induced by LPS in piglets' serum and intestine by inhibiting the activation of the Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB)/mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, compared to the LPS group, supplementation with EO + OA restored LPS-induced reductions in Bcl-2 protein expression in the piglets' intestines (P < 0.05) and mitigated morphological damage; it also enhanced both the protein expression and relative gene expression of the tight junction proteins occludin and claudin-1 (P < 0.05), and reduced the plasma diamine oxidase activity (DAO) and LPS content (P < 0.05). Compared to the CON group, supplementation with EO + OA altered the composition of the intestinal microbiota, increasing beneficial bacteria relative abundance (Faecalibacterium) (P < 0.05) and decreasing harmful bacteria relative abundance [Rikenellaceae_RC9_gut_group (P < 0.01), Negativibacillus (P < 0.05)]. Further analysis revealed that plasma LPS content in piglets was negatively correlated with the relative abundance of Faecalibacterium (r = -0.662, P = 0.021), Akkermansia (r = -0.492, P = 0.031), and average daily gain (ADG) (r = -0.912, P = 0.041). Plasma LPS content was also positively correlated with the plasma inflammatory factors interleukin (IL)-1β (r = 0.591, P = 0.021), IL-6 (r = 0.623, P = 0.021), IL-12 (r = 561, P = 0.031) contents, and the relative abundance of Negativibacillus (r = 0.712, P = 0.041). In summary, the addition of EO + OA prevents the leakage of intestine derived LPS into the circulation by improving intestinal integrity and microbiota composition, thereby enhancing antioxidant and anti-inflammatory abilities and growth performance of weaned piglets.

Effects of different combinations of antibacterial compound supplements in calf pellets on growth performance, health, blood parameters, and rumen microbiome of dairy calves

This study investigated the effects of different combinations of antibacterial compounds (attapulgite, plant essential oils, and chitosan oligosaccharides) on growth performance, blood biochemical parameters, and rumen microbiome of calves. A total of 48 preweaning calves were randomly divided into four groups (n = 12 per group), and fed the following full mixed-ration granule diets for the 67-d-feeding trial: (1) basal diet (control group); (2) basal diet +1,000 g/t attapulgite, plant essential oils, and chitosan oligosaccharide (AEOCO group); (3) basal diet +1,000 g/t attapulgite and chitosan oligosaccharide (ACO group); and (4) basal diet +1,000 g/t attapulgite and plant essential oil (AEO group). The results showed that the daily weight gain of the AEOCO and AEO groups significantly increased (p < 0.05), whereas the feed conversion ratio decreased compared with that of the control group. Among the three treatment groups, AEO group showed the most positive effect, with the diarrhea rate reduced by 68.2% compared with that of the control group. Total protein and globulin levels were lower in the AEO group than in the control group. Albumin levels were higher in the AEOCO and AEO groups than in the control group. Immunoglobulin A, immunoglobulin G, and immunoglobulin M concentrations were higher in the AEOCO group (p < 0.05) than in the control group. The interleukin-6 concentration was lower in the AEOCO and AEO groups than in the control group (p < 0.05). The Chao 1 richness and ACE indices were higher in the AEOCO group than in the control group (p < 0.05). The ACO group had a significantly lower (p < 0.05) relative abundance of Firmicutes than the control group. The relative abundance of Bacteroidetes was the lowest in the control group, whereas that of Spirochaetota and Fibrobacteriota was the highest (p < 0.05). The relative abundance of Succiniclasticum was higher in the ACO and AEO groups (p < 0.05). These findings indicate that the combination of attapulgite, plant essential oils, and chitosan oligosaccharides has ameliorative effects on the growth performance, blood parameters, and rumen microbiome of calves.

Effects of microencapsulated essential oils and organic acids preparation on growth performance, slaughter characteristics, nutrient digestibility and intestinal microenvironment of broiler chickens

To develop effective antibiotics alternatives is getting more and more important to poultry healthy production. The study investigated the effects of a microencapsulated essential oils and organic acids preparation (EOA) on growth performance, slaughter performance, nutrient digestibility and intestinal microenvironment of broilers. A total of 624 1-day-old male Arbor Acres broilers were randomly divided into 6 groups including the control group (T1) fed with basal diet, the antibiotic group (T2) supplemented with basal diet with 45 mg/kg bacitracin methylene disalicylate (BMD), and 4 inclusion levels of EOA-treated groups (T3, T4, T5, T6 groups) chickens given basal diet with 200, 400, 600, and 800 mg EOA/kg of diet, respectively. Results showed that compared with the control, the 200 mg/kg EOA group increased average daily gain (ADG) and average body weight (ABW) during the early stage (P < 0.05). EOA addition decreased crypt depth of the ileum (P < 0.05), but villus height to crypt depth ratio was increased by EOA addition at 200 and 400 mg/kg at d 21 (P < 0.05). Compared with the control, dietary addition EOA at 200, 400 and 600 mg/kg increased the lipase activity in the duodenum at d 21 (P < 0.05). Increased lactic acid bacteria population was found in cecal digesta of the 400 mg/kg EOA group at d 21 (P < 0.05), and higher concentration of butyric acid level was observed in cecal digesta at d 21 and d 42 in the 200 mg/kg EOA group compared with the control (P < 0.05). RT-PCR analysis found that dietary EOA addition decreased the gene expression of IL-1β, COX-2 and TGF-β4 in the ileum at d 21 (P < 0.05), while only the 200 mg/kg EOA increased the gene expression of IL-10, TGF-β4, Claudin-1, ZO-1, CATH-1, CATH-3, AvBD-1, AvBD-9 and AvBD-12 in the ileum at d 42 (P < 0.05) compared with the control. In summary, adding 200 mg/kg and 400 mg/kg of the EOA to the diet could improve the growth performance and intestinal microenvironment through improving intestinal morphology, increasing digestive enzymes activity and cecal lactic acid bacteria abundance and butyric acid content, improving intestinal barrier function as well as maintaining intestinal immune homeostasis. The improving effect induced by EOA addition in the early growth stage was better than that in the later growth stage. Overall, the EOA product might be an effective antibiotic alternative for broiler industry.

Essential oils improve nursery pigs' performance and appetite via modulation of intestinal health and microbiota

Optimal intestinal health and functionality are essential for animal health and performance, and simultaneously intestinal nutrient transporters and intestinal peptides are also involved in appetite and feed intake control mechanisms. Given the potential of essential oil (EO) in improving animal performance and improving feed palatability, we hypothesized that dietary supplementation of cinnamaldehyde and carvacrol could improve performance and appetite of nursery pigs by modulating intestinal health and microbiota. Cinnamaldehyde (100 mg/kg), carvacrol (100 mg/kg), and their mixtures (including 50 mg/kg cinnamaldehyde and 50 mg/kg carvacrol) were supplemented into the diets of 240 nursery pigs for 42 d, and data related to performance were measured. Thereafter, the influence of EO on intestinal health, appetite and gut microbiota and their correlations were explored. EO supplementation increased (P < 0.05) the body weight, average daily gain (ADG) and average daily feed intake (ADFI) of piglets, and reduced (P < 0.05) diarrhea rates in nursery pigs. Furthermore, EO increased (P < 0.05) the intestinal absorption area and the abundance of tight junction proteins, and decreased (P < 0.05) intestinal permeability and local inflammation. In terms of intestinal development and the mucus barrier, EO promoted intestinal development and increased (P < 0.05) the number of goblet cells. Additionally, we found that piglets in the EO-supplemented group had upregulated (P < 0.05) levels of transporters and digestive enzymes in the intestine, which were significantly associated with daily gain and feed utilization. In addition, EO supplementation somewhat improved appetite in nursery pigs, increased the diversity of the gut microbiome and the abundance of beneficial bacteria, and there was a correlation between altered bacterial structure and appetite-related hormones. These findings indicate that EO is effective in promoting growth performance and nutrient absorption as well as in regulating appetite by improving intestinal health and bacterial structure.

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.

Dietary Supplementation of Mixed Organic Acids Improves Growth Performance, Immunity, and Antioxidant Capacity and Maintains the Intestinal Barrier of Ira Rabbits

The aim of this study was to investigate the effects of mixed organic acids (MOAs) on growth performance, immunity, antioxidants, intestinal digestion, and barrier function in Ira rabbits. A total of 192 weaned male Ira rabbits at 35 days of age were randomly assigned to four groups with six replicates of eight rabbits each. The rabbits in the control group (CON) were fed a basal diet, and the antibiotic group (SAL) was fed a basal diet supplemented with 60 mg/kg salinomycin. The test groups were fed a basal diet supplemented with 1000 mg/kg and 2000 mg/kg MOAs (MOA1 and MOA2, respectively). The experiment lasted for 55 days. The results showed that the ADG of Ira rabbits in the SAL group and MOA1 group was higher than that in the CON group (p < 0.05). The serum IL-6 and liver MDA levels of Ira rabbits in the SAL group, MOA1 group, and MOA2 group were lower than those in the CON group (p < 0.05). In addition, sIgA levels in the jejunal mucosa of Ira rabbits in the SAL group and MOA1 group were increased compared with those in the CON group (p < 0.05). Compared with the CON group, the gene expression of IL-6 was decreased (p < 0.05) in the jejunal mucosa of Ira rabbits in the SAL, MOA1, and MOA2 groups, while the gene expression of IL-1β tended to decrease (p = 0.077) and the IL-10 content tended to increase (p = 0.062). Moreover, the gene expression of ZO-1 in the jejunal mucosa of Ira rabbits was elevated in the MOA1 group compared with the CON group (p < 0.05). In conclusion, dietary supplementation with MOAs can improve growth performance, enhance immune function and antioxidant capacity, and maintain the intestinal barrier in weaned Ira rabbits.

Synergistic antimicrobial system based on nisin and α-hydroxy organic acids

Synergistic antimicrobial is a promising way to overcome microbial contamination in food and drugs. In the study, the synergistic effect between nisin and α-hydroxy organic acids on E. coli and S. aureus was investigated. The experimental results showed that the combined antibacterial ability of nisin-citric acid system was the most prominent. The FCI index also indicated that the combination of nisin and citric acid had synergistic effects on E. coli. When nisin was combined with citric acid, the inhibition rates of E. coli and S. aureus were increased to 4.43 and 1.49 times, respectively. Nisin-citric acid complex system could effectively slow down the proliferation of S. aureus and E. coli at lower concentrations, and can quickly destroy the cell membrane after 4 h of action. Therefore, the combination of nisin and citric acid is expected to be a potential solution for food and drug preservation.

Effects of fermented soybean meal supplementation on the growth performance and apparent total tract digestibility by modulating the gut microbiome of weaned piglets

This study investigates the effects of soybean meal fermented by Enterococcus faecium as a replacement for soybean meal on growth performance, apparent total tract digestibility, blood profile and gut microbiota of weaned pigs. Eighty piglets (weaned at 21 days) [(Landrace × Yorkshire) × Duroc] with average body weight of 6.52 ± 0.59 kg) were selected and assigned to 4 treatments/4 replicate pens (3 barrows and 2 gilts). The four diets (SBM, 3, 6 and 9% FSBM) were formulated using fermented soybean meal to replace 0, 3, 6 and 9% of soybean meal, respectively. The trial lasted for 42 days phase 1, 2 and 3. Result showed that supplemental FSBM increased (P < 0.05) the body weight gain (BWG) of piglets at day 7, 21 and 42 and ADG at days 1-7, 8-21, 22-42 and 1-42, and ADFI at days 8-21, 22-42 and 1-42 and G: F at days 1-7, 8-21 and 1-42, and crude protein, dry matter, and gross energy digestibility at day 42, and lowered (P < 0.05) diarrhea at days 1-21 and 22-42. The concentration of glucose levels, WBC, RBC, and lymphocytes were increased while, concentration of BUN level in the serum was lowered in the FSBM treatment compared to the SBM group (P < 0.05). Microbiota sequencing found that FSBM supplementation increased the microbial Shannon, Simpsons and Chao indexs, (P < 0.05) and the abundances of the phylum Firmicutes, and genera prevotella, Lactobacillus, Lachnospiraceae and Lachnoclostridium (P < 0.05), lower in the abundances of the phylum bacteroidetes, Proteobacteria, genera Escherichia-Shigella, Clostridium sensu stricto1, Bacteroides and Parabacteroides (P < 0.05). Overall, FSBM replacing SBM improved the growth performance, apparent total tract digestibility, and blood profiles; perhaps via altering the faecal microbiota and its metabolites in weaned pigs. The present study provides theoretical support for applying FSBM at 6-9% to promote immune characteristics and regulate intestinal health in weaning piglets.

Dietary Supplementation with Probiotic Bacillus licheniformis S6 Improves Intestinal Integrity via Modulating Intestinal Barrier Function and Microbial Diversity in Weaned Piglets

Bacillus licheniformis (B. Licheniformis) has been considered to be an effective probiotic to maintain gut health and boost productivity in the pig industry, but there is no complete understanding of its mechanisms. We determined whether weaned piglets exposed to BL-S6 (probiotic) had altered intestinal barrier function or microbiota composition. In our study, 108 weaned piglets (54 barrows and 54 gilts) were divided equally into three groups, each with six pens and six piglets/pen, and fed a basal diet supplemented without or with antibiotic (40 g/t of Virginiamycin and 500 g/t of Chlortetracycline) or probiotic (1000 g/t of B. Licheniformis) for a 14-day trial. On day 14, one piglet was chosen from each pen to collect blood and intestinal samples. Compared with the control group, dietary supplementation with a probiotic promoted body weight (BW) gain and average daily gains (ADG) while reducing diarrhea incidence (p < 0.05). Probiotics enhanced superoxidase dismutase (SOD) activity and decreased malondialdehyde (MDA) levels in serum (p < 0.05), and increased the level of mRNA expression of SOD1, Nrf2, and HO-1 (p < 0.05) in the jejunum mucosa. Moreover, supplementation with probiotics improved intestinal mucosal integrity as evidenced by higher villus heights and a higher ratio of villus heights to crypt depths (duodenum and jejunum) and higher mRNA and protein levels of occludin and ZO-1 in jejunum mucosa (p < 0.05). The intestinal sIgA levels (p < 0.05) were elevated in the probiotic group, and that of serum immunoglobulin A (IgA) tended to be higher (p = 0.09). Furthermore, weaning piglets who were given probiotics had a better balance of the cecum microbiota, with lactobacillus abundance increased and clostridium_sensu_stricto_1 abundance decreased. In conclusion, dietary supplementation with the probiotic BL-S6 promoted intestinal integrity, which was associated, in part, with modulating intestinal barrier function and microbial diversity in weaned piglets; it may offer a promising alternative to antibiotics to prevent diarrhea.

Effect of Dietary Supplemented with Mulberry Leaf Powder on Growth Performance, Serum Metabolites, Antioxidant Property and Intestinal Health of Weaned Piglets

Background: The study aimed to explore the effect of mulberry leaf powder (MP) on the performance, serum metabolites and antioxidant property, as well as intestinal health, of weaned piglets. A total of 120 healthy piglets weighing 8.43 ± 1.91 kg (Duroc × (Landrace × Yorkshire); weaned at 28 d) were chosen and classified into four treatments with three replicates of 10 piglets each based on a randomized complete block design (barrow:gilt = 1:1). The diet treatments were a corn-soybean meal basal diet added with 0% (Ctrl), 2% (MP_2), 4% (MP_4) and 6% MP (MP_6), respectively. The feeding experiment was 28 days in total. The feeding period lasted for 28 days in total. Results: The diet supplemented with 2% MP had no detrimental effects on the growth performance, immunity, enzyme capacity and inflammatory factors, as well as intestinal barrier function. MP_2 is capable of decreasing the levels of serum D-lactic acid and lactate dehydrogenase, enhancing the superoxide dismutase capacity in the liver and diminishing the potential pathogenic bacteria Allisonella in the colon. However, compared with MP_2, MP_6 had unfavorable effects on the average daily gain and average daily feed intake; the concentration of serum non-esterified fatty acids; the activities of superoxide dismutase and glutathione peroxidase and the capacity of lipase and amylase, as well as the intestinal barrier function-related mRNA expression of occludin, claudin-1 and mucin-2 in piglets. Conclusion: Taken together, piglets fed with 2% MP had no adverse effect and was capable of improving the serum metabolites, enhancing the antioxidant capacity (SOD) and lowering the potential pathogenic bacteria of the hindgut (Allisonella). However, the highest concentration of MP (6%) may cause detrimental effects for piglets, which are probably associated with the higher antinutritional factors and fiber. Therefore, the dietary supplementation of 2% MP for piglets may be advisable.

Encapsulated Essential Oils Improve the Growth Performance of Meat Ducks by Enhancing Intestinal Morphology, Barrier Function, Antioxidant Capacity and the Cecal Microbiota

The objective of this study was to evaluate the effects of encapsulated essential oils (EOs) on the gut microbiota, growth performance, intestinal morphology, antioxidant properties and barrier function of meat-type ducks. A total of 320 male Cherry Valley ducks (1 day old), were randomly assigned to four dietary experimental groups with eight replicates of ten ducks each. The groups consisted of the CON group (basal diet), the HEO group (basal diet + EO 1000 mg/kg), the LEO group (basal diet + EO 500 mg/kg), and the ANT group (basal diet + chlortetracycline 50 mg/kg). Our findings indicated that ducks fed with EO 1000 mg/kg had greater average daily feed intake (ADFI), average daily gain (ADG), and body weight (BW) and a lower feed conversion ratio (FCR) than the other groups. The serum concentration of TG reduced in the HEO (p > 0.05) and LEO (p < 0.05) groups on day 42, while the concentration of CHOL increased with the EO concentration in the LEO (p > 0.05) and HEO (p < 0.05) groups. No differences were observed in the ileal mucosa for the activities of SOD, MPO and GSH-PX after EO dietary treatment. Dietary supplementation with EOs significantly increased the villus heights (p < 0.01) and the ratio of villus height to crypt depth (c/v) in the duodenum and jejunum of ducks. Moreover, the mRNA expressions of Claudin1 and Occludin in the jejunal mucosa were observed to be higher in the LEO and HEO groups rather than the CON and ANT groups on d 42. The α diversity showed that the HEO group improved the bacterial diversity and abundance. The β diversity analysis indicated that the microbial structures of the four groups were obviously separated. EO dietary supplementation could increase the relative abundance (p < 0.01) of the Bacteroidetes phylum, Bacteroidaceae family, and Bacteroides, Desulfovibrio, Phascolarctobacterium, and Butyricimonas genera in the cecal microbiota of ducks. We demonstrated significant differences in the bacterial composition and functional potential of the gut microbiota in ducks that were fed either an EO diet or a basal diet. Therefore, supplemented EOs was found to have a positive effect on the growth performance and intestinal health of ducks, which was attributed to the improvement in cecal microbiota, intestinal morphology, and barrier function.

Lycopene Affects Intestinal Barrier Function and the Gut Microbiota in Weaned Piglets via Antioxidant Signaling Regulation

BACKGROUND

In pig production, early and abrupt weaning frequently causes weaning stress, which manifests as oxidative damage, barrier disruption, and digestion and absorption capacity declines. Lycopene exhibits beneficial antioxidant capacity in both humans and other animal models.

OBJECTIVES

The present study aimed to investigate the effects of lycopene supplementation on early weaning stress in piglets and the underlying mechanisms by examining the oxidative stress state, gut intestinal barrier function, and the gut microbiota.

METHODS

Twenty-four 21-day-old weaned piglets [Duroc × (Landrace × Yorkshire); castrated males; 5.48 ± 0.10 kg initial body weight] were randomly assigned to 2 treatments. The piglets were fed a basal diet (control treatment) or a basal diet supplemented with 50 mg/kg lycopene (lycopene treatment) for 28 days. The serum lipid levels, serum and jejunum enzyme activities, jejunum morphology, mRNA and protein expression, and gut microbiota were determined.

RESULTS

Compared with the control treatment, lycopene supplementation increased the serum catalase activity (P = 0.042; 62.0%); serum total cholesterol concentration (P = 0.020; 14.1%); and jejunum superoxide dismutase activity (P = 0.032; 21.4%), whereas it decreased serum (P = 0.039, 23.0%) and jejunum (P = 0.047; 20.9%) hydrogen peroxide concentrations. Additionally, lycopene increased the mRNA and protein expression of NFE2-like bZIP transcription factor 2 (214.0% and 102.4%, respectively) and CD36 (100.8% and 145.2%, respectively) in the jejunum, whereas it decreased the mRNA and protein expression of Kelch-like ECH-associated protein 1 (55.6% and 39.8%, respectively ). Lycopene also improved jejunal morphology, increasing the villus height (P = 0.018; 27.5%) and villus:crypt ratio (P < 0.001; 57.9%). Furthermore, it increased the abundances of potentially beneficial bacterial groups, including Phascolarctobacterium and Parasutterella, and decreased those of potentially pathogenic bacterial groups, including Treponema_2 and Prevotellaceae_unclassified.

CONCLUSIONS

Lycopene supplementation strengthens the intestinal barrier function and improves the gut microbiota in weaned piglets by regulating intestinal antioxidant signaling.

An Encapsulated Organic Acid and Essential Oil Mixture Improves the Intestinal Health of Weaned Piglets by Altering Intestinal Inflammation and Antioxidative Capacity

This study investigates the effects of an encapsulated organic acid and essential oil mixture (OAEO) on the growth performance, immuno-antioxidant capacity and intestinal health of weaned piglets. In total, 120 weaned piglets (23 days of age; 6.96 ± 0.08 kg) were randomly allotted to four treatments (six replicates/group; five piglets/replicate): the control group (CON) was fed the basal diet (BD), the antibiotic growth promoters group (AGP) received the BD with 20 mg/kg colistin sulphate and 10 mg/kg bacitracin zinc, and OAEO1 and OAEO2 were fed the BD with 1000 mg/kg and 2000 mg/kg OAEO, respectively. The trial lasted 21 days and then one piglet per replicate was selected for sample collection. OAEO increased the average daily gain, spleen index, serum interleukin (IL)-10, immunoglobulin (Ig) G and IgA levels; serum superoxide dismutase and glutathione peroxidase (GPX) activities; and jejunal villus height (VH), VH/crypt depth, goblet cell number, and amylase and trypsin activities (p < 0.05) compared with CON but reduced the diarrhea rate, serum tumor necrosis factor (TNF)-α, malondialdehyde (MDA), and D-lactic acid contents and diamine oxidase (DAO) activity (p < 0.05). OAEO also increased the jejunal zonula occludens-1, occludin, claudin-1, mucin-2, nuclear factor erythroid 2-related factor 2 (Nrf2), GPX and IL-10 mRNA levels, GPX activity and IL-10 content (p < 0.05) compared with CON but reduced jejunal MDA, IL-1β and TNF-α contents and Toll-like receptor (TLR) 4, nuclear factor (NF)-κB and TNF-α mRNA levels (p < 0.05). In addition, AGP increased ADG, serum IgA level and GPX activity, jejunal trypsin activity and IL-10 content and mRNA level (p < 0.05) compared with CON but reduced the serum TNF-α content and DAO activity and jejunal NF-κB mRNA level (p < 0.05). Overall, OAEO as an alternative to AGP improved the growth performance, immuno-antioxidant status and gut health of weaned piglets partly via activating the Nrf2 signaling pathway and suppressing the TLR4/NF-κB signaling pathway.

A Meta-Analysis of Essential Oils Use for Beef Cattle Feed: Rumen Fermentation, Blood Metabolites, Meat Quality, Performance and, Environmental and Economic Impact

The objective of this study was to see how dietary supplementation with essential oils (EOs) affected rumen fermentation, blood metabolites, growth performance and meat quality of beef cattle through a meta-analysis. In addition, a simulation analysis was conducted to evaluate the effects of EOs on the economic and environmental impact of beef production. Data were extracted from 34 peer-reviewed studies and analyzed using random-effects statistical models to assess the weighted mean difference (WMD) between control and EOs treatments. Dietary supplementation of EOs increased (p < 0.01) dry matter intake (WMD = 0.209 kg/d), final body weight (WMD = 12.843 kg), daily weight gain (WMD = 0.087 kg/d), feed efficiency (WMD = 0.004 kg/kg), hot carcass weight (WMD = 5.45 kg), and Longissimus dorsi muscle area (WMD = 3.48 cm2). Lower (p < 0.05) ruminal concentration of ammonia nitrogen (WMD = −1.18 mg/dL), acetate (WMD = −4.37 mol/100 mol) and total protozoa (WMD = −2.17 × 105/mL), and higher concentration of propionate (WMD = 0.878 mol/100 mol, p < 0.001) were observed in response to EOs supplementation. Serum urea concentration (WMD = −1.35 mg/dL, p = 0.026) and haptoglobin (WMD = −39.67 μg/mL, p = 0.031) were lower in cattle supplemented with EOs. In meat, EOs supplementation reduced (p < 0.001) cooking loss (WMD = −61.765 g/kg), shear force (WMD = −0.211 kgf/cm2), and malondialdehyde content (WMD = −0.040 mg/kg), but did not affect pH, color (L* a* and b*), or chemical composition (p > 0.05). Simulation analysis showed that EOs increased economic income by 1.44% and reduced the environmental footprint by 0.83%. In conclusion, dietary supplementation of EOs improves productive performance and rumen fermentation, while increasing the economic profitability and reducing the environmental impact of beef cattle. In addition, supplementation with EOs improves beef tenderness and oxidative stability.