Effects of increasing dietary arginine supply during the three first weeks after weaning on pig growth performance, plasma amino acid concentrations, and health status

A total of 425 weaned pigs (Exp. 1: 225 pigs [5.8 ± 0.9 kg]; Exp. 2: 200 pigs [6.1 ± 1.2 kg]) were used to determine the optimal dietary standardized ileal digestible (SID) arginine (Arg) level in early nursery diets based on growth and health responses. The basal diet in Exp.1 was formulated to meet SID Arg recommendation (0.66%; NRC, 2012) and in Exp. 2, SID Arg was set to simulate current industry practices for feeding nursery pigs (1.15 %). Basal diets were supplemented with 0.3%, 0.6%, 0.9%, and 1.2% of l-arginine to provide five levels of dietary SID Arg. Experimental diets were fed during phases I (days 0 to 7) and II (days 8 to 21) with common diets until market. Feed disappearance and body weight (BW) were measured on days 7, 14, 21, and 43. Final BW was recorded at first removal of pigs for market. Pen fecal score was assigned daily from days 0 to 21. Plasma immunoglobulin A (IgA) was determined on days 0, 7, and 14 and amino acids (AAs) concentration and plasma urea nitrogen (PUN) on days 0 and 14. Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of dietary Arg. Optimal SID Arg was determined by fitting the data with piecewise regression, using growth performance as the primary response variable. In Exp. 1, dietary Arg linearly increased (P < 0.1) BW, average daily gain (ADG), and gain to feed ratio (G:F) ratio on day 21, as well as reduced (χ2 = 0.004) the percentage of pigs that lost weight (PLW) in week 1 by 29%. Dietary Arg resulted in linear improvement (P = 0.082) of ADG for the overall nursery period and quadratic improvement (P < 0.1) of final BW at marketing. In Exp. 2, dietary Arg linearly increased (P < 0.05) ADG and average daily feed intake (ADFI) in week 1, BW and ADFI (P < 0.1) on day 14, as well as reduced (χ2 ≤ 0.001) PLW in week 1. From days 0 to 21, G:F was improved quadratically (P < 0.1). Dietary Arg linearly increased (P < 0.1) ADG and BW on day 43. Dietary Arg supplementation decreased the incidence (χ2 < 0.05) of soft and watery feces during the first weeks after weaning and lower concentration of plasma IgA on days 7 and 14. Dietary Arg linearly and/or quadratically influenced plasma AA concentrations (P < 0.05), including an increase in Arg, Leu, Phe, Val, citrulline, ornithine, and PUN concentrations. Overall, weaned pigs exhibit optimal nursery growth performance and health when provided with dietary SID Arg ranging from 1.5% to 1.9%. This dietary range contributes to a reduction in the occurrence of fall-back pigs and improvements in final BW at marketing.

Growth Performance, Metabolomics, and Microbiome Responses of Weaned Pigs Fed Diets Containing Growth-Promoting Antibiotics and Various Feed Additives

The objective of this study was to determine the potential biological mechanisms of improved growth performance associated with potential changes in the metabolic profiles and intestinal microbiome composition of weaned pigs fed various feed additives. Three separate 42 day experiments were conducted to evaluate the following dietary treatments: chlortetracycline and sulfamethazine (PC), herbal blends, turmeric, garlic, bitter orange extract, sweet orange extract, volatile and semi-volatile milk-derived substances, yeast nucleotide, and cell wall products, compared with feeding a non-supplemented diet (NC). In all three experiments, only pigs fed PC had improved (p < 0.05) ADG and ADFI compared with pigs fed NC. No differences in metabolome and microbiome responses were observed between feed additive treatments and NC. None of the feed additives affected alpha or beta microbiome diversity in the ileum and cecum, but the abundance of specific bacterial taxa was affected by some dietary treatments. Except for feeding antibiotics, none of the other feed additives were effective in improving growth performance or significantly altering the metabolomic profiles, but some additives (e.g., herbal blends and garlic) increased (p < 0.05) the relative abundance of potentially protective bacterial genera that may be beneficial during disease challenge in weaned pigs.

Porcine ear necrosis: characterization of lesions and associated pathogens

Porcine ear necrosis (PEN) is characterized by ulcerative lesions of the ear auricle. To investigate that problem, three farms with PEN in nursery pigs were included, and the study aim was to characterize PEN and the potential role of pathogens and mycotoxins. Within each farm, one batch of weaned piglets was included and the prevalence and severity of PEN were monitored for 6-7 weeks. Within each batch, 30 PEN-affected/non-affected animals were randomly selected. Blood samples were taken from these animals, to assess the systemic presence of pathogens and mycotoxins, as well as punch biopsies from the ear auricle for histopathological examination. From 10 animals, scrapings and swabs from the lesions were subjected to nanopore metagenomic sequencing and bacteriological cultivation, respectively. In all three farms, lesions appeared within 3-4 weeks post-weaning. The prevalence at the end of the nursery was 33%, 24%, and 46% for farms A, B, and C, respectively. Most affected pigs had mild to moderate lesions. Blood samples revealed low to very low levels of pathogens and mycotoxins. Different bacteria such as Staphylococcus, Streptococcus, Fusobacterium, Mycoplasma, and Clostridium species were identified by sequencing in the scrapings. The first two pathogens were also most often identified in bacterial cultures. Mycoplasma hyopharyngis was only found in PEN-affected pigs. Histopathological changes were primarily observed in the outer layer of the epidermis. The results suggest that PEN lesions develop by damage to the outer part of the skin e.g. by ear suckling or biting, followed by multiplication of opportunistic pathogens.

Effect of Different Dietary Lipid Sources on Growth Performance, Nutrient Digestibility, and Intestinal Health in Weaned Pigs

To investigate the effects of lipid sources on growth performance and intestinal health, 72 weaned pigs were randomly allocated to three treatments. Pigs were fed with a corn-soybean meal diet containing 2% soybean oil (SO), or fish-palm-rice oil mixture (FPRO), or coconut-palm-rice oil mixture (CPRO). The trial lasted for 28 days; blood and intestinal tissue samples were collected. The results showed that the crude fat digestibility of the FPRO group was higher than that of the SO and CPRO groups (p < 0.05). The FPRO group also had higher digestibility of dry matter, ash, and gross energy than the SO group (p < 0.05); compared to the SO group, the serum interlukin-6 (IL-6) concentration was decreased. Interestingly, the FPRO and CPRO groups had higher villus height than the SO group in the jejunum and ileum, respectively (p < 0.05). Moreover, the FPRO group had higher Lactobacillus abundance than the SO group in the colon and cecum (p < 0.05). Importantly, the expression levels of tight junction protein ZO-1, Claudin-1, and Occludin in the duodenal and ileal mucosa were higher in the FPRO group than in the SO and CPRO groups (p < 0.05). The expression levels of nutrient transporters such as the CAT-1, PepT1, FATP1, and SGLT1 were higher in the FPRO group than in the SO group (p < 0.05). The improved digestibility and intestinal epithelium functions, as well as the reduced inflammatory cytokines, in the FPRO and CPRO group suggest that a mixed lipid source such as the FPRO deserves further attention.

Functional Characterization and Toxicological Study of Proanthocyanidins in Weaned Pigs

Proanthocyanidin (PRO) has been implicated in a variety of biological functions, such as antibacterial, antioxidant, and anti-obesity effects. However, little is known about its safety dose for animals. To explore its safety and effect on growth performance and intestinal health, thirty weaned pigs were divided into five groups and fed with basal diet containing 0, 30, 300, 600, and 1200 mg/kg PRO for 42 days. Results showed that PRO supplementation at 30 and 300 mg/kg significantly decreased the feed/gain ratio (F:G) and diarrhea rate (p < 0.05). PRO also increased the digestibilities of dry matter, ether extract, gross energy, and ash (p < 0.05). Interestingly, PRO not only elevated the villus height and the ratio of villus height to crypt depth (V/C) in duodenum and jejunum (p < 0.01), but also decreased the crypt depth in the duodenum (p < 0.01). Moreover, PRO supplementation at 30, 300, and 600 mg/kg elevated the expression levels of mucin 1 (MUC1), MUC2, and fatty acid transport protein 1 (FATP-1) in the duodenum (p < 0.05). The expression levels of FATP-4 in jejunum and ileum were also elevated by PRO (p < 0.05). Importantly, histopathological findings of tissues (e.g., heart, liver, kidney, spleen, lungs, pancreas, thymus, mesenteric lymph nodes, stomach, small intestine), serum clinical chemistry, and major hematological parameters were not affected by PRO supplementation. These results suggest that PRO may act as a safe and effective supplement to decrease F:G and improve intestinal health in weaned pigs.

Innovative Use of Olive, Winery and Cheese Waste By-Products as Novel Ingredients in Weaned Pigs Nutrition

New sustainable sources of feeds, which can enhance the health and welfare of farm animals, lower feeding costs, and lead to safer products, are of high priority in modern animal production systems. In the present study, a novel silage created from Greek olive, winery, and feta cheese waste by-products, was evaluated as a feed ingredient at different inclusion rates (0%, 5% or 10%) in 34-day-old weaned pigs. The potential beneficial effects on performance, health and intestinal digesta microflora balance of the pigs were evaluated. Additionally, chemical, microbiological and quality analysis of the meat was carried out. Results showed no detrimental effects (p > 0.05) on the pigs' performance and no significant changes (p > 0.05) in meat pH, color and chemical analysis. Ileum and cecum microflora populations (total anaerobes, Lactobacillaceae) were positively affected (p ≤ 0.05) by the dietary usage of the silage. The microbial populations (Clostridium spp.) of belly meat cuts were positively modified (p ≤ 0.01). The concentration of total phenols in the meat cuts were increased (p ≤ 0.05) and their resistance to oxidation was improved (p ≤ 0.05). In addition, the fatty acid profile of the meat lipids (polyunsaturated and n-3 fatty acids) was positively modified (p ≤ 0.001).

Gut-Faecal Microbial and Health-Marker Response to Dietary Fumonisins in Weaned Pigs

This study investigated effects of dietary fumonisins (FBs) on gut and faecal microbiota of weaned pigs. In total, 18 7-week-old male pigs were fed either 0, 15 or 30 mg FBs (FB₁ + FB₂ + FB₃)/kg diet for 21 days. The microbiota was analysed with amplicon sequencing of the 16S rRNA gene V3-V4 regions (Illumina MiSeq). Results showed no treatment effect (p > 0.05) on growth performance, serum reduced glutathione, glutathione peroxidase and malondialdehyde. FBs increased serum aspartate transaminase, gamma glutamyl-transferase and alkaline phosphatase activities. A 30 mg/kg FBs treatment shifted microbial population in the duodenum and ileum to lower levels (compared to control (p < 0.05)) of the families Campylobacteraceae and Clostridiaceae, respectively, as well as the genera Alloprevotella, Campylobacter and Lachnospiraceae Incertae Sedis (duodenum), Turicibacter (jejunum), and Clostridium sensu stricto 1 (ileum). Faecal microbiota had higher levels of the Erysipelotrichaceae and Ruminococcaceae families and Solobacterium, Faecalibacterium, Anaerofilum, Ruminococcus, Subdoligranulum, Pseudobutyrivibrio, Coprococcus and Roseburia genera in the 30 mg/kg FBs compared to control and/or to the 15 mg/kg FBs diets. Lactobacillus was more abundant in the duodenum compared to faeces in all treatment groups (p < 0.01). Overall, the 30 mg/kg FBs diet altered the pig gut microbiota without suppressing animal growth performance.

Different Fatty Acid Supplementation in Low-Protein Diets Regulate Nutrient Utilization and Lipid and Amino Acid Metabolism in Weaned Pigs Model

This study was conducted to evaluate the effects of a low-protein (LP) diet supplemented with sodium butyrate (SB), medium-chain fatty acids (MCFAs) and n-3 polyunsaturated fatty acids (PUFAs) on nutrient utilization and lipid and amino acid metabolism in weaned pigs. A total of 120 Duroc × Landrace × Yorkshire pigs (initial body weight: 7.93 ± 0.65 kg) were randomly assigned to five dietary treatments, including the control diet (CON), LP diet, LP + 0.2% SB diet (LP + SB), LP + 0.2% MCFA diet (LP + MCFA) and LP + 0.2% n-3 PUFA diet (LP + PUFA). The results show that the LP + MCFA diet increased (p < 0.05) the digestibility of dry matter and total P in pigs compared with the CON and LP diets. In the liver of the pigs, the metabolites involved in sugar metabolism and oxidative phosphorylation significantly changed with the LP diet compared with the CON diet. Compared with the LP diet, the altered metabolites in the liver of the pigs fed with the LP + SB diet were mainly associated with sugar metabolism and pyrimidine metabolism; the altered metabolites in the liver of pigs fed with the LP + MCFA and LP + PUFA diets were mainly associated with lipid metabolism and amino acid metabolism. In addition, the LP + PUFA diet increased (p < 0.05) the concentration of glutamate dehydrogenase in the liver of pigs compared with the LP diet. Furthermore, the LP + MCFA and LP + PUFA diets increased (p < 0.05) the mRNA abundance of sterol regulatory element-binding protein 1 and acetyl-CoA carboxylase in the liver compared with the CON diet. The LP + PUFA diet increased (p < 0.05) mRNA abundances of fatty acid synthase in the liver compared with the CON and LP diets. Collectively, the LP diet supplemented with MCFAs improved nutrient digestibility, and the LP diet supplemented with MCFAs and n-3 PUFAs promoted lipid and amino acid metabolisms.

A dietary spray-dried plasma feeding programme improves growth performance and reduces faecal bacterial shedding of nursery pigs challenged with enterotoxigenic Escherichia coli K88

This study aimed to assess the effects of different spray-dried plasma (SDP) feeding programmes to pigs on performance, intestinal histomorphology and faecal bacterial shedding after an Escherichia coli K88 challenge. A total of 96 piglets (5.77 ± 0.01 kg) were weaned at 21 days of age (Day 0) and challenged with 3 ml of 1 × 10¹⁰  CFU of E. coli K88 in total 3.0 × 10¹⁰  CFU/animal on Days 0, 2 and 4. Pigs were fed nursery diets containing 0.0%, 3.0%, 6.0% or 9.0% SDP from weaning to 35 days of age; 0.0%, 1.5%, 3.0% or 4.5% SDP from 36 to 49 days; and the same control diet (without SDP), for the last 10 days of the experiment (50-59 days of age). Performance was measured from 35 to 59 days of age and faecal bacterial shedding and intestinal histomorphometry were evaluated at Days 28 and 49 of age respectively. From 21 to 35 days of age, there was a linear effect for body weight (BW) and average daily gain (ADG), a trend of linear effect for average daily feed intake (ADFI) and a quadratic effect for feed:gain ratio (FG). From 21 to 49 days, the 9.0:4.5% and 6.0:3.0% SDP feeding programmes improved BW, ADG and FG when compared to the other treatments. At 59 days of age, BW and ADG were increased by the two highest SDP feeding programmes. The 9.0:4.5% SDP feeding programme increased ADFI from 21 to 59 days of age, with 6.0:3.0% being intermediate and the other two treatments being lowest. The CFU counts of E. coli/g of faeces decreased linearly with increasing addition of SDP. These results indicate that an extended inclusion of increased SDP levels in post-weaning diets can improve growth potential and decrease bacterial shedding induced by E. coli K88.

Dietary Supplementation with Botanical Blends Modified Intestinal Microbiota and Metabolomics of Weaned Pigs Experimentally Infected with Enterotoxigenic Escherichia coli

The objective of this study was to investigate supplementation of botanical blends (BB) comprised of 0.3% capsicum oleoresin and 12% garlic oil on gut microbiota and metabolomic profiles in serum and ileal mucosa of Escherichia coli infected pigs. Sixty weaned pigs were assigned to one of five treatments: negative control (CON-), positive control (CON+), dietary supplementation of 100 ppm BB1, 50 or 100 ppm BB2. All pigs, except CON-, were orally inoculated with 10¹⁰ CFU F18 ETEC/3-mL dose for 3 consecutive days after 7 d adaption. Feces, ileal digesta and cecal content were collected for 16S rRNA amplicon sequencing. Serum and ileal mucosa underwent primary metabolomics analysis. Supplementing 100 ppm BB1 increased (p < 0.05) relative abundances of Enterobacteriaceae and Escherichia-Shigella in ileum, and the relative abundances of Bacteroidota and Prevotellaceae in cecum than CON+ on d 5 post-inoculation (PI). Supplementing 100 ppm BB2 upregulated serum pinitol on d 4 PI and serum cholesterol and aminomalonic acids on d 21 PI, while supplementing 50 ppm BB2 reduced asparagine in ileal mucosa on d 5 PI than CON+. Supplementation with botanical blends modulated ileal and cecal microbiota and serum metabolomics profiles in weaned pigs under Escherichia coli challenge.

Effect of 3-caffeoylquinic acid on growth performance, nutrient digestibility, and intestinal functions in weaned pigs

Phenolic acid like with the 3-caffeoylquini acid (3-CQA) is formed by caffeic acid and qunic acid. This study was conducted to explore the effect of 3-CQA on growth performance and intestinal functions in weaned pigs. A total of 180 weaned pigs were randomly allocated into five treatments with 6 replicate pens per treatment (6 pigs per pen). Pigs in the control group (CON) were fed with basal diet (BD), and the others in the experimental groups were fed with BD and supplemented with 12.5, 25, 50, and 100 mg/kg 3-CQA. On day 43, the blood sample-collected pigs in the CON and optimal-dose group (only based on growth performance) were picked, and housed in metabolism cages (a total of 12 pigs, N = 6). 3-CQA increased the feed efficiency from days 21 to 42 of the trial and throughout the trial (P < 0.05). 3-CQA increased the serum concentrations of total protein, albumin, and total cholesterol (P < 0.05). Moreover, 3-CQA supplementation at 25 mg/kg increased the apparent digestibility of DM, energy, and ash (P < 0.05). Interestingly, 3-CQA decreased the crypt depth but increased the ratio of villus height to crypt depth in the jejunum and ileum (P < 0.05). Moreover, 3-CQA also increased the activities of sucrase, lactase, and catalase in the jejunal mucosa, and increased the activities of alkaline phosphatase and superoxide dismutase in the ileal mucosa (P < 0.05). 3-CQA also increased the abundance of secretory immunoglobulin A in the ileal mucosa (P < 0.05). Importantly, 3-CQA not only elevated the expression levels of critical functional genes such as the zonula occludens-1 , occludin, solute carrier family 7 , and nuclear factor erythroid 2-related factor 2 (Nrf2) in the duodenum but also elevated the expression levels of divalent metal transporter-1 and Nrf2 in the jejunum (P < 0.05). These results suggested a positive effect of 3-CQA supplementation on the growth and intestinal functions of weaned pigs. The mechanisms of action may be associated with elevated anti-oxidant capacity and improved intestinal barrier functions.

Dietary butyrate and valerate glycerides impact diarrhea severity and immune response of weaned piglets under ETEC F4-ETEC F18 coinfection conditions

Enterotoxigenic Escherichia coli (ETEC) causes post-weaning diarrhea in piglets, significantly impacting animal welfare and production efficiency. The two primary ETEC pathotypes associated with post-weaning diarrhea are ETEC F4 and ETEC F18. During the post-weaning period, piglets may be exposed to both ETEC F4 and ETEC F18. However, the effects of coinfection by both strains have not been studied. Short chain fatty acid feed additives, such as butyrate and valerate, are being investigated for their potential to improve animal performance and disease resistance. Therefore, this pilot experiment aimed to test the effects of butyrate glycerides or valerate glycerides on growth performance, diarrhea incidence, and immune responses of piglets under ETEC F4-ETEC F18 coinfection conditions. Twenty piglets were individually housed and assigned to one of the three dietary treatments immediately at weaning (21 to 24 d of age). The dietary treatments included control (basal diet formulation), control supplemented with 0.1% butyrate glycerides or 0.1% valerate glycerides. After a 7-d adaptation, all pigs were inoculated with ETEC F4 and ETEC F18 (0.5 × 109 CFU/1.5 mL dose for each strain) on three consecutive days. Pigs and feeders were weighed throughout the trial to measure growth performance. Fecal cultures were monitored for hemolytic coliforms, and blood samples were collected for whole blood and serum analysis. Pigs fed valerate glycerides tended (P = 0.095) to have higher final body weight compared with control. The overall severity of diarrhea was significantly (P < 0.05) lower in both treatment groups than control. Pigs fed valerate glycerides tended (P = 0.061) to have lower neutrophils and had significantly (P < 0.05) lower serum TNF-α on day 4 post-inoculation. This pilot experiment established an appropriate experimental dose for an ETEC F4-ETEC F18 coinfection disease model in weaned piglets. Results also suggest that butyrate glycerides and valerate glycerides alleviated diarrhea and regulated immune responses in piglets coinfected with ETEC F4 and ETEC F18.

Dietary supplementation of Bacillus subtilis or antibiotics modified intestinal microbiome of weaned pigs under enterotoxigenic Escherichia coli infection

Our previous research reported that supplementation of Bacillus subtilis DSM 25841 promoted growth and disease resistance of weaned pigs under enterotoxigenic Escherichia coli (ETEC) challenge and its efficacy is comparable to carbadox. This follow-up study aimed to characterize the effects of ETEC infection, supplementing B. subtilis DSM 25841 or carbadox on intestinal microbiota of pigs. Forty-eight weaned pigs (6.17 ± 0.36 kg BW) were randomly allotted to one of four treatments: negative control (NC), positive control (PC), antibiotics (AGP, 50 mg/kg of carbadox), and direct fed microbials (DFM, 2.56 × 10⁹  CFU/kg of B. subtilis). The experiment lasted 28 days with 7 days before and 21 days after first E. coli inoculation (day 0). Pigs in the PC, AGP, and DFM groups were orally inoculated with F18 ETEC for 3 consecutive days with 10¹⁰  CFU per dose per day. Fecal samples were collected on day -7, and day 7 and day 21 post inoculation, digesta samples were collected from jejunum, ileum, and distal colon on day 21 post inoculation to perform 16S rRNA sequencing. Sampling days and locations influenced (p < 0.05) Chao1 index and beta-diversity. Age increased (p  < 0.05) the relative abundance of Firmicutes but decreased (p < 0.05) the relative abundance of Bacteroidetes in feces. ETEC infection increased (p  < 0.05) the relative abundance of Proteobacteria in feces on day 7 post inoculation. AGP reduced (p < 0.05) relative abundance of Firmicutes and Lactobacillaceae in feces compared with PC and DFM. AGP reduced (p < 0.05) relative abundance of Bifidobacteriaceae in jejunum and ileum, while DFM reduced (p < 0.05) relative abundance of Actinomycetaceae in jejunum and Lachnospiraceae in ileum, compared with PC. Pigs fed with DFM had greater (p < 0.05) relative abundance of Ruminococcaceae, Veillonellaceae, Bifidobacteriaceae in jejunum, Lactobacillaceae in ileum and colon, and Bifidobacteriaceae in colon than pigs in AGP. Current results indicate that carbadox or B. subtilis had stronger influences on microbial diversity and composition in ileum than other intestinal segments and feces. Supplementation of B. subtilis could increase or maintain the relative abundance of beneficial bacteria in ileum compared with carbadox.

Dietary supplementation of botanical blends enhanced performance and disease resistance of weaned pigs experimentally infected with enterotoxigenic Escherichia coli F18

Botanicals exhibit promising impacts on intestinal health, immune-regulation, and growth promotion in weaned pigs. However, these benefits may vary depending on major active components in the final feed additive products. Therefore, this study aimed to investigate two types of botanical blends (BB) that were comprised of 0.3% capsicum oleoresin and 12% garlic extracts from different sources on performance, diarrhea, and health of weaned piglets experimentally infected with a pathogenic Escherichia coli F18. Sixty weanling pigs (7.17 ± 0.97 kg body weight (BW)) blocked by weight and gender were assigned to one of five dietary treatments: negative control (NC), positive control (PC), or dietary supplementation with 100 mg/kg of BB1, 50 mg/kg or 100 mg/kg of BB2. This study lasted 28 d with 7 d before and 21 d after the first E. coli inoculation (day 0). All pigs, except negative control, were orally inoculated with 1010 cfu E. coli F18/3-mL dose for 3 consecutive days. Blood samples were collected periodically to analyze systemic immunity. Intestinal tissues and mucosa were collected on days 5 and 21 PI for analyzing histology and gene expression. All data, except for frequency of diarrhea, were analyzed by ANOVA using the PROC MIXED of SAS. The Chi-square test was used for analyzing frequency of diarrhea. Escherichia coli infection reduced (P < 0.05) growth rate and feed intake and increased (P < 0.05) frequency of diarrhea of weaned pigs throughout the experiment. Supplementation of 100 mg/kg BB1 or BB2 alleviated (P < 0.05) frequency of diarrhea of E. coli challenged pigs during the entire experiment. Escherichia coli infection also enhanced (P < 0.05) serum TNF-α and haptoglobin concentrations on day 4 post-inoculation (PI) but reduced (P < 0.05) duodenal villi height and area on day 5 PI, while pigs supplemented with 100 mg/kg BB1 or BB2 had lower (P < 0.05) serum TNF-α than pigs in PC on day 4 PI. Pigs fed with 100 mg/kg BB2 had higher (P < 0.05) jejunal villi height than pigs in PC on day 5 PI. Pigs fed with 100 mg/kg BB2 had reduced (P < 0.05) gene expression of IL1B, PTGS2, and TNFA in ileal mucosa than pigs in PC on day 21 PI. In conclusion, dietary supplementation of botanical blends at 100 mg/kg could enhance disease resistance of weaned pigs infected with E. coli F18 by enhancing intestinal morphology and regulating local and systemic immunity of pigs.

Eugenol Attenuates Transmissible Gastroenteritis Virus-Induced Oxidative Stress and Apoptosis Via ROS-NRF2-ARE Signaling

Transmissible gastroenteritis virus (TGEV), a coronavirus that causes severe diarrhea due to oxidative stress in the piglet intestine, is a major cause of economic loss in the livestock industry. However, limited interventions have been shown to be effective in the treatment of TGEV. Here, we demonstrate the therapeutic activity of eugenol in TGEV-induced intestinal oxidative stress and apoptosis. Our data show that eugenol supplementation protects intestine and IPEC-J2 cells from TGEV-induced damage. Mechanistically, eugenol reduces TGEV-induced oxidative stress in intestinal epithelial cells by reducing reactive oxygen species levels. Interestingly, eugenol also inhibits TGEV-induced intestinal cell apoptosis in vitro and in vivo. In conclusion, our data suggest that eugenol prevents TGEV-induced intestinal oxidative stress by reducing ROS-mediated damage to antioxidant signaling pathways. Therefore, eugenol may be a promising therapeutic strategy for TGEV infection.

ZX09 β-Glucan Attenuates Enterotoxigenic Escherichia coli-Induced Disruption of Intestinal Epithelium in Weaned Pigs

To explore the protective effect of dietary β-glucan (BGL) supplementation on intestinal epithelium exposure to enterotoxigenic Escherichia coli (ETEC), thirty-two weaned pigs were assigned to four groups. Pigs were fed with a basal diet or basal diet containing 500 mg/kg BGL, and were orally infused with ETEC or culture medium. Results showed BGL supplementation had no influence on growth performance in weaned pigs. However, BGL supplementation increased the absorption of D-xylose, and significantly decreased the serum concentrations of D-lactate and diamine oxidase (DAO) in the ETEC-challenged pigs (p < 0.05). Interestingly, BGL significantly increased the abundance of the zonula occludens-1-(ZO-1) in the jejunal epithelium upon ETEC challenge (p < 0.05). BGL supplementation also increased the number of S-phase cells and the number of sIgA-positive cells, but significantly decreased the number of total apoptotic cells in the jejunal epithelium upon ETEC challenge (p < 0.05). Moreover, BGL significantly increased the duodenal catalase (CAT) activity and the ileal total superoxide dismutase (T-SOD) activity in the ETEC-challenged pigs (p < 0.05). Importantly, BGL significantly decreased the expression levels of critical inflammation related proteins such as the tumor necrosis factor-α (TNF-α), interlukin-6 (IL-6), myeloid differentiation factor 88 (MyD88), and nuclear factor-κB (NF-κB) in the jejunal and ileal mucosa upon ETEC challenge (p < 0.05). BGL also elevated the propanoic acid content and the abundance of Lactobacillus and Bacillus in the colon upon ETEC challenge (p < 0.05). These results suggested BGL could alleviate the ETEC-induced intestinal epithelium injury, which may be associated with suppressed inflammation and improved intestinal immunity and antioxidant capacity, as well as the improved intestinal macrobiotic.

Drinking Water Supplemented with Acidifiers Improves the Growth Performance of Weaned Pigs and Potentially Regulates Antioxidant Capacity, Immunity, and Gastrointestinal Microbiota Diversity

This study evaluated the potential effects of adding acidifiers to the drinking water on the growth performance, complete blood count, antioxidant indicators, and diversity of gastrointestinal microbiota for weaned pigs. A total of 400 weaned pigs were randomly divided into four treatments. Pigs were fed the same basal diet and given either water (no acidifier was added, control) or water plus blends of different formulas of acidifiers (acidifier A1, A2, or A3) for 35 days. On d 18 and 35 of the experimental period, 64 pigs (four pigs per pen) were randomly selected to collect blood for a CBC test (n = 128) and an antioxidant indicators test (n = 128); 24 pigs (six pigs per group) were randomly selected to collect fresh feces (n = 48) from the rectum for 16S rRNA gene sequencing. Compared to the control, supplementing the drinking water with acidifiers improved the growth performance and survival rate of weaned pigs. Acidifier groups also increased serum catalase (CAT) and total antioxidant capacity (T-AOC) activities, while also displaying a decreased malondialdehyde (MDA) concentration compared to the control. The relative abundance of Firmicutes in the acidifier A1 group was greater than that in the control group (p < 0.05) on d 35; the relative abundance of Lactobacillus in the acidifier A1 group was greater than that in the control group (p < 0.05) on d 18 and 35. The microbial species Subdoligranulum or Ruminococcaceae_UCG-005 had significantly positive correlations with ADG and ADFI or with serum antioxidant indicators, respectively. These findings suggest that supplementing the drinking water with an acidifier has a potential as an antioxidant, which was reflected in the improvement of growth performance, immunity, antioxidant capacity, and intestinal flora.

Effect of β-Glucan Supplementation on Growth Performance and Intestinal Epithelium Functions in Weaned Pigs Challenged by Enterotoxigenic Escherichia coli

Background: To examine the effect of β-glucan (BGL) supplementation on growth performance and intestinal epithelium functions in weaned pigs upon Enterotoxigenic Escherichia coli (ETEC) challenge. Methods: Thirty-two weaned pigs (Duroc × Landrace × Yorkshire) were assigned into four groups. Pigs fed with a basal diet or basal diet containing 500 mg/kg BGL were orally infused with ETEC or culture medium. Results: Results showed BGL tended to increase the average daily gain (ADG) in ETEC-challenged pigs (0.05 < p < 0.1). Dietary BGL supplementation had no significant influence on nutrient digestibility (p > 0.05). However, BGL improved the serum concentrations of immunoglobulin (Ig) A and IgG, and was beneficial to relieve the increasement of the concentrations of inflammatory cytokines such as the TNF-α and IL-6 upon ETEC-challenge (p < 0.05). Interestingly, BGL significantly increased the duodenal, jejunal and ileal villus height, and increased the jejunal ratio of villus height to crypt depth (V/C) upon ETEC challenge (p < 0.05). BGL also increased the activities of mucosal, sucrase and maltase in the ETEC-challenged pigs (p < 0.05). Moreover, BGL elevated the abundance of Lactobacillus and the concentration of propanoic acid in colon in the ETEC-challenged pigs (p < 0.05). Importantly, BGL elevated the expression levels of zonula occludins-1 (ZO-1) and mucin-2 (MUC-2) in the small intestinal mucosa upon ETEC challenge (p < 0.05). BGL also upregulated the expressions of functional genes such as the claudin-1, cationic amino acid transporter-1 (CAT-1), LAT-1, L amino acid transporter-1 (LAT1), fatty acid transport proteins (FATP1), FATP4, and sodium/glucose cotransporter-1 (SGLT-1) in the duodenum, and the occludin-1 and CAT-1 in the jejunum upon ETEC challenge (p < 0.05). Conclusions: These results suggested that BGL can attenuate intestinal damage in weaned pigs upon ETEC challenge, which was connected with the suppressed secretion of inflammatory cytokines and enhanced serum immunoglobulins, as well as improved intestinal epithelium functions and microbiota.

Alteration of Porcine Intestinal Microbiota in Response to Dietary Manno-Oligosaccharide Supplementation

Manno-oligosaccharide (MOS) is a prebiotic derived from natural plants or yeasts. Here, we explored the response of intestinal microbiota and epithelial functions after ingestion of MOS in a porcine model. Sixteen pigs were randomly assigned into two treatments and fed with basal or MOS-containing (0.3% MOS) diet for 21 days. Results showed that MOS supplementation increased the cecal acetate content and ileal 16S rRNA gene copies (p < 0.05). Importantly, MOS decreased the abundance of phylum Proteobacteria in cecal digesta (p < 0.05). Moreover, MOS elevated the expression level of SCL5A8 and GPR109A but decreased the expression levels of HDAC1 and TNF-α in the ileal and cecal mucosa (p < 0.05). MOS upregulated the expression levels of tight-junction protein (ZO-1, claudin-1, and occludin) and IGF-1 in the ileum and cecum (p < 0.05). This study presents the alteration of intestinal microbiota composition and intestinal barrier function after MOS administration, and facilitates our understanding of the mechanisms behind the dietary MOS-modulated intestinal microbiota and health.

Effects of compound of hawthorn (Crataegus pinnatifida) and Chinese yam (Dioscorea opposita Thunb.) extracts on growth performance, intestinal health, and immune function in weaned pigs

Plant extracts were considered as natural resources to alleviate weaning stress in pig production. A 28-day study (Phase 1: d 0-14 and Phase 2: d 15-28) was conducted to investigate the effects of compound of hawthorn and yam extracts on growth performance, intestinal health, and immune function in weaned pigs. A total of 144 weaned pigs with average body weight (BW) of 7.89 ± 1.09 kg were assigned to three treatments with six replicates pens by BW and sex. Dietary treatments included negative control (NC), corn-soybean meal basal diet; positive control (PC), NC + 0.08% enzyme preparations and 0.3% acidifiers; and CHY, NC + 0.3% compound of hawthorn and yam extracts. Compared with NC-fed pigs, pigs fed CHY had greater (p < 0.05) growth performance in Phase 1. The CHY-fed pigs had greater (p < 0.05) activities of duodenal lipase, trypsin, and greater (p < 0.05) serum concentrations of total antioxidant capacity and glutathione peroxidase. The CHY-fed pigs had improved (p < 0.05) jejunal morphology and greater (p < 0.05) ileac valeric acid and colonic propionic acid, isobutyric acid concentrations than NC- and PC-fed pigs. In conclusion, CHY can improve growth performance and is a promising additive in weaned pig diets.

Supplementation with Exogenous Catalase from Penicillium notatum in the Diet Ameliorates Lipopolysaccharide-Induced Intestinal Oxidative Damage through Affecting Intestinal Antioxidant Capacity and Microbiota in Weaned Pigs

The present study aimed to explore the protective effects of exogenous catalase (CAT) from microorganisms against lipopolysaccharide (LPS)-induced intestinal injury and its molecular mechanism in weaned pigs. Fifty-four weaned pigs (21 days of age) were randomly allocated to CON, LPS, and LPS+CAT groups. The pigs in CON and LPS groups were fed a basal diet, whereas the pigs in LPS+CAT group fed the basal diet with 2,000 mg/kg CAT supplementation for 35 days. On day 36, six pigs were selected from each group, and LPS and LPS+CAT groups were administered with LPS (50 μg/kg body weight). Meanwhile, CON group was injected with an equivalent amount of sterile saline. Results showed that LPS administration damaged intestinal mucosa morphology and barrier. However, CAT supplementation alleviated the deleterious effects caused by LPS challenge through enhancing intestinal antioxidant capacity which was benefited to decrease proinflammatory cytokines concentrations and suppress enterocyte apoptosis. Besides, LPS-induced gut microbiota dysbiosis was significantly shifted by CAT through decreasing mainly Streptococcus and Escherichia-Shigella. Our study suggested that dietary supplemented with 2,000 mg/kg catalase was conducive to improve intestinal development and protect against LPS-induced intestinal mucosa injury via enhancing intestinal antioxidant capacity and altering microbiota composition in weaned pigs.

IMPORTANCE Exogenous CAT derived from microorganisms has been widely used in food, medicine, and other industries. Recent study also found that exogenous CAT supplementation could improve growth performance and antioxidant capacity of weaned pigs. However, it is still unknown that whether dietary exogenous CAT supplementation can provide a defense against the oxidative stress-induced intestinal damage in weaned pigs. Our current study suggested that dietary supplemented with 2,000 mg/kg CAT was conducive to improve intestinal development and protect against LPS-induced intestinal mucosa injury via enhancing intestinal antioxidant capacity and altering microbiota composition in weaned pigs. Moreover, this study will also assist in developing of CAT produced by microorganisms to attenuate various oxidative stress-induced injury or diseases.

Effects of a blend of essential oils, medium-chain fatty acids and a toxin-adsorbing mineral on diarrhea and gut microbiome of weanling pigs experimentally infected with a pathogenic E. coli

A proprietary antimicrobial feed additive comprised of essential oils, medium-chain fatty acids, and a toxin-adsorbing mineral showed promising bacteriostatic and bactericidal effects in vitro. This study investigated the impacts of supplementing this blend on growth, gut microbiome, and enteric disease resilience in weaned pigs experimentally challenged with an enterotoxigenic Escherichia coli (ETEC). Thirty-six weanling pigs (6.88 ± 0.30 kg body weight (BW)) blocked by weight and gender were assigned to one of three dietary treatments: control or dietary supplementation with 0.25% or 0.50% of the antimicrobial blend. This study lasted 28 d with 7 d before and 21 d after the first ETEC inoculation (d 0). All pigs were orally inoculated with 10 10 cfu F18+ ETEC/3-mL dose for 3 consecutive days. Growth performance data and diarrhea scores were recorded throughout the experiment. Fecal samples collected on d -7, 0, 7 and 21 post first inoculation (PI), and ileal digesta and mucosal tissue collected on d 21 PI were further analyzed for gut microbiome using 16S rRNA sequencing. All data, except for frequency of diarrhea and gut microbiome, were analyzed by ANOVA using the PROC MIXED of SAS. The Chi-square test was used for analyzing frequency of diarrhea. Gut microbiome data were analyzed using QIIME2 and visualized using the R program. Dietary supplementation of 0.25% or 0.5% of the antimicrobial blend increased (P < 0.05) feed efficiency on d 14 to 21 PI of ETEC and reduced (P < 0.05) frequency of diarrhea during the study. Compared to the control group, adding 0.5% dietary antimicrobial blend increased (P < 0.05) relative abundance of Firmicutes but reduced (P < 0.05) Bacteroidetes and Proteobacteria in feces on d 7 PI. Pigs that received the antimicrobial blend also had higher (P < 0.05) relative abundance of Lactobacillaceae, but lower (P < 0.05) relative abundance of Enterobacteriaceae in feces on d 7 PI than pigs in control. In conclusion, supplementation of this antimicrobial blend at 0.5% reduced incidence of severe diarrhea in weaned pigs challenged with F18 ETEC and enhanced feed efficiency of weaned pigs at the last week of the experiment. Supplementation of this antimicrobial blend also modified the microbiota diversity in feces and ileal mucosa of weaned pigs.

Fermented Alfalfa Meal Instead of "Grain-Type" Feedstuffs in the Diet Improves Intestinal Health Related Indexes in Weaned Pigs

Corn and soybean meal are the two main components in formula feed of farm animals, leading to a serious food competition between humans and livestock. An alternative may be to encourage the utilization of unconventional feedstuff in animal diet. In the current study, we evaluated the utilization of fermented alfalfa meal (FAM) in weaned pigs. Twenty weaned piglets (separately caged) were randomly divided into two groups. Pigs in the control group (CON) were fed corn-soybean meal diet, and part of corn and soya protein concentrate in the diet of another group was replaced by 8% FAM. After 40 days of feeding, the average feed intake of FAM pigs was increased (P > 0.05), and the villus height (VH) of jejunum and duodenum, crypt depth (CD), and VH/CD in FAM pigs was improved compared to the CON group (P < 0.05). The increase (P < 0.05) of goblet cells in the jejunum of FAM pigs was positively correlated with the expression of MUC-2 gene (R = 0.9150). The expression of genes related to immunity (IRAK4, NF-κB, and IL-10) and intestinal barrier (Occludin and MUC-2) in the jejunum, as well as the expression of ZO-1 and MUC-2 in the colon of these pigs, also showed increase (P < 0.05) compared to CON pigs, which was accompanied by the decrease (P < 0.05) of LPS concentration in the serum. The elevated proportion of CD3+ and CD8+ T-lymphocyte subsets in spleen (P < 0.05) confirmed the improvement of systemic immune function in FAM pigs. In addition, FAM pigs have a higher β-diversity of microbial community (P < 0.05) and promoted enrichment of probiotics such as Lactobacillus that positively was correlated with acetate concentration in the colon over CON pigs. In summary, partially replacement of expanded corn and soya protein concentrate with FAM (8%) may benefit the intestinal barrier and immune function of weaned pigs without affecting their growth. Our findings also provide evidence of the feasibility of FAM as a dietary component in pigs to reduce the consumption of grain.

reuteri LR1 on Growth Performance, Antioxidant Function, and Intestinal Immunity in Weaned Pigs

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

Chlorogenic Acid Attenuates Oxidative Stress-Induced Intestinal Epithelium Injury by Co-Regulating the PI3K/Akt and IκBα/NF-κB Signaling

Chlorogenic acid (CGA) is a natural polyphenol compound abundant in green plants with antioxidant and anti-inflammatory activities. Here, we explore its protective effects and potential mechanisms of action on intestinal epithelium exposure to oxidative stress (OS). We show that CGA attenuated OS-induced intestinal inflammation and injury in weaned pigs, which is associated with elevated antioxidant capacity and decreases in inflammatory cytokine secretion and cell apoptosis. In vitro study showed that CGA elevated phosphorylation of two critical signaling proteins of the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) pathway, Akt and nuclear factor erythroid-derived-related factor 2, leading to the elevated expression of intracellular antioxidant enzymes and heme oxygenase-1 (HO-1). Specific inhibition of HO-1 partially abolished its anti-inflammatory effect in IPEC-J2 cells exposure to OS. Interestingly, CGA suppressed the tumor necrosis factor-α (TNF-α) induced inflammatory responses in IPEC-J2 cells by decreasing phosphorylation of two critical inflammatory signaling proteins, NF-kappa-B inhibitor alpha (IκBα) and nuclear factor-κB (NF-κB). Specific inhibition of HO-1 cannot fully abolish its anti-inflammatory effect on the TNF-α-challenged cells. These results strongly suggested that CGA is a natural anti-inflammatory agent that can attenuate OS-induced inflammation and injury of intestinal epithelium via co-regulating the PI3K/Akt and IκBα/NF-κB signaling pathway.

Probiotics and Achyranthes bidentata Polysaccharides Improve Growth Performance via Promoting Intestinal Nutrient Utilization and Enhancing Immune Function of Weaned Pigs

Simple Summary

It is frequent to see that in-feed antibiotics are added to piglets diets because of their enteric problems after weaning. However, in-feed antibiotics have been forbidden to used in livestock production since 1 July 2020 in China. Therefore, it is urgent to develop some promising alternatives to in-feed antibiotics. Probiotics and plant extracts are considered to be the potential replacements, which have been studied or applied in animal production. In our study, we found that probiotic or Achyranthes bidentata polysaccharides used alone or in combination, the combination augmenting the positive effect more than the independent supplement, could improve piglets’ growth performance via promoting intestinal nutrient digestion and absorption and enhancing immune funtion, and the beneficial role was comparable to that of the selected in-feed antibiotics.

Abstract

The experiment aimed to investigate the effects of probiotics and Achyranthes bidentata polysaccharides on the growth performance, nutrients digestibility, and immune function of weaned pigs. One hundred and twenty weaned pigs (about 7 kg BW, 23 ± 2 d) were allotted to five dietary treatments (CON: antibiotics-free basal diet; ANT: CON + antibiotics; PRO: CON + probiotics; ABPS: CON + Achyranthes bidentata polysaccharides; P-ABPS: PRO + ABPS) for a 28-day trial. Compared with CON, pigs in ANT, PRO, ABPS, and P-ABPS had greater (p < 0.05) ADG, ATTD of CP and GE, serum ALB, IgA and IL-2, duodenal intraepithelial lymphocyte, ileal VH and jejunal mucosa sIgA, but lower (p < 0.05) fecal scores, serum BUN, and IL-1β. Meanwhile, ANT, PRO, ABPS, and P-ABPS exhibited similar beneficial roles on growth performance, nutrients digestibility, serum parameters, and immune function. Interestingly, P-ABPS effects were similar to those obtained with ANT rather than with PRO or ABPS. In conclusion, Dietary PRO or ABPS used alone or in combination (P-ABPS), the combination augmenting the positive effect more than the independent supplement, could improve piglets’ growth performance via promoting intestinal nutrient digestion and absorption and enhancing immune function, indicating it had the potential to act as an alternative to in-feed antibiotics used in piglet diets.

Dietary Yeast Cell Wall Improves Growth Performance and Prevents of Diarrhea of Weaned Pigs by Enhancing Gut Health and Anti-Inflammatory Immune Responses

Simple Summary

Post-weaning stress can substantially affect performance of weaned pigs as well as overall pig production, and thus, a practical approach is needed to improve their performance by alleviating the stress that can cause intestinal barrier dysfunction of weaned pigs. There are potential ways to solve the concern in swine production, but dietary yeast cell wall in weaner diets may be one possible solution. The results of the present study suggest that dietary yeast cell wall improves growth performance of weaned pigs by enhancing gut health and provide its potential mechanism.

Abstract

Dietary yeast cell wall products (YCW) are recognized as a feed additive due to multifunctional benefits by the biological response modulators. Thus, this study was conducted to verify a potential advantage of YCW for improving growth performance, nutrient digestibility, immune responses, and intestinal health and microbiota of weaned pigs. A total of 112 weaned pigs (7.99 ± 1.10 kg of body weight; 28 days old) were arbitrarily allocated to two experimental treatments with eight pigs (four barrows and four gilts) per pen and seven replicate pens per treatment in a completely randomized block design (block = BW and sex): (1) a basal diet based on corn and soybean meal (CON) and (2) CON + 0.05% YCW. The experimental period was for 4 weeks. There were no differences in final body weight, average daily feed intake, and gain-to-feed ratio between dietary treatments. In contrast, pigs fed YCW had higher average daily gain (p = 0.088) and apparent ileal digestibility of DM (p < 0.05) and energy (p = 0.052) and lower diarrhea frequency (p = 0.083) than those fed control diet (CON). Pigs fed YCW also had a higher (p < 0.05) ratio between villus height and crypt depth, villus width and area, and goblet cell counts in the duodenum and/or jejunum than those fed CON. Dietary YCW decreased (p < 0.05) serum TNF-α and IL–1β of weaned pigs on day 7 and 14, respectively, compared with CON. Furthermore, pigs fed YCW had higher (p < 0.05) ileal gene expression of claudin family, occludin, MUC1, INF-γ, and IL-6 and lower (p < 0.05) that of TNF-α than those fed CON. Lastly, there were no differences in the relative abundance of bacteria at the phylum level between CON and YCW. However, dietary YCW increased (p < 0.05) the relative abundance of genera Prevotella and Roseburia compared with CON. This study provided that dietary YCW improved growth rate, nutritional digestibility, and intestinal health and modified immune responses and intestinal microbiota of weaned pigs.

Effects of Weaning Age at 21 and 28 Days on Growth Performance, Intestinal Morphology and Redox Status in Piglets

The study objective was to assess effects of different weaning ages on growth performance, intestinal morphology and redox status in Duroc × Landrace × Large White piglets (n = 96) fed diets without antibiotic growth promoters. Piglets were selected from 24 litters based on similar body weight at 14 d of age. All piglets were allocated to two groups in a completely random design with six replicates and eight pigs per replicate (four barrows and four gilts), which were weaned at 21 (n = 48; BW = 6.87 ± 0.33 kg) and 28 (n = 48; BW = 8.49 ± 0.41 kg) days of age. After weaning, pigs were fed a corn-soybean meal-based diet. Average daily gain (ADG), average daily feed intake (ADFI), feed conversion (F:G), diarrhea incidence, gastrointestinal pH, intestinal morphology and redox status were determined. Pigs weaned at 28 d displayed increased ADG from d 8 to 14 (p < 0.01) compared with pigs weaned at 21 d. Pigs weaned at 28 d had a higher ADFI from d 0 to 7 (p < 0.01), d 8 to 14 (p < 0.01), d 15 to 28 (p < 0.05) and during the entire experimental period (p < 0.01) compared with pigs weaned at 21 d. Pigs weaned at 21 d had an improved F:G from d 15 to 28 (p < 0.05) compared with pigs weaned at 28 d. Pigs weaned at 28 d had decreased diarrhea incidence from d 8 to 14 (p < 0.01) and the entire experimental period (p < 0.01) compared with pigs weaned at 21 d. On d 28, the pH of the stomach contents in pigs weaned at 21 d was significantly higher compared with pigs weaned at 28 d (p < 0.01). On d 14, the morphology of the duodenum, jejunum and ileum in pigs weaned at 28 d was improved compared with pigs weaned at 21 d. During the experiment period, the antioxidant abilities of pigs weaned at 28 d of the heart, liver, kidney, intestinal and serum were better than pigs weaned at 21 d. In conclusion, intestinal morphology, pH of the stomach and antioxidant status of pigs weaned at 28 d were better than pigs weaned at 21 d. These factors supported better growth performance and decreased diarrhea incidence.

Isolation, Identification and Function of Pichia anomala AR2016 and Its Effects on the Growth and Health of Weaned Pigs

This study isolates and identifies Pichia anomala (P. anomala) AR₂₀₁₆, and studies its effect on the growth and health of weaned pigs. A P. anomala strain from solid wine koji is isolated and identified using 26S rDNA analysis, and its culture conditions are optimized. Heat tolerance, bile salt tolerance, artificial gastric, and intestinal juice tolerance are evaluated. In our methodology, thirty 28 d Large White × Landrace × Rongchang weaned pigs were randomly divided into three groups with 10 barrows in each, and fed a maize-soybean meal diet and orally administered 0.85% saline (CK), 1 mL 1 × 10⁹ cfu/mL Candida utilis (C. utilis), and 1 mL 1 × 10⁹ cfu/mL P. anomala once daily for 28 days. A P. anomala strain was identified and named P. anomala AR₂₀₁₆. P. anomala AR₂₀₁₆ grew best in yeast extract peptone dextrose medium with pH 5.0 at 28 °C, 180 r/min and could tolerate 45 °C for 0.5 h, 0.2% pig bile salts, simulated gastric fluid, and 1.0% simulated intestinal fluid. Our results show that compared with the CK group, orally administered P. anomala AR₂₀₁₆ increases average daily gain, the ileal villus height, the ileal mucosal concentrations of occludin and zonula occluens-1, the serum glucose and total protein concentration, total superoxide dismutase, glutathione peroxidase, and total antioxidative capacity activity, the trypsin and lipase activity in jejunal and ileal contents, the jejunal and ileal mucosa mRNA levels of ALP, TNF-α, and TLR-2, and the relative abundance of Bacteroidetes, Actinobacteria, Succinivibrionaceae, Lachnospiraceae, and Prevotellaceae (p < 0.05). Compared with the CK group, oral administration of P. anomala AR₂₀₁₆ decreased the incidence of diarrhea, aspartate aminotransferase activity, alanine amino-transferase-activity, malondialdehyde, D-lactic acid and endotoxin content in serum, the mRNA level of aminopeptidase N of ileum mucosa, and the relative abundance of Proteobacteria, Clostridiaceae, Campylobacteraceae, Vibrionaceae, Bacillus, and Pseudon (p < 0.05). Collectively, the study indicates that P. anomala AR₂₀₁₆ can tolerate high acidity and high bile salts, and has high survivability in the artificial gastric intestinal juice environment. Oral administration of P. anomala AR₂₀₁₆ improves the growth performance, reduces the incidence of diarrhea, enhances intestinal barrier function, and improves microflora in weaned pigs.

Trace amounts of antibiotic exacerbated diarrhea and systemic inflammation of weaned pigs infected with a pathogenic Escherichia coli

The experiment was conducted to investigate the effects of trace amounts of antibiotic on growth performance, diarrhea, systemic immunity, and intestinal health of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli. Weaned pigs (n = 34, 6.88 ± 1.03 kg body weight [BW]) were individually housed in disease containment rooms and randomly allotted to one of the three dietary treatments: nursery basal diet (CON) and two additional diets supplemented with 0.5 or 50 mg/kg carbadox to the nursery basal diet (TRA or REC), respectively. The experiment lasted 18 d with 7 d before and 11 d after the first E. coli inoculation. The E. coli F18 inoculum was orally provided to all pigs with a dose of 1010 colony-forming unit (CFU)/3 mL for three consecutive days. Fecal and blood samples were collected on day 0 before inoculation and days 2, 5, 8, and 11 postinoculation (PI) to test the percentage of β-hemolytic coliforms in total coliforms and complete blood cell count, respectively. Sixteen pigs were euthanized on day 5 PI, whereas the remaining pigs were euthanized at the end of the experiment to collect the jejunal and ileal mucosa and mesenteric lymph node for gene expression and bacterial translocation, respectively. Pigs in REC had greater (P < 0.05) final BW and lower (P < 0.05) overall frequency of diarrhea compared with pigs in the CON and TRA groups. Pigs in TRA had the lowest (P < 0.05) average daily gain and feed efficiency from day 0 to 5 PI, highest (P < 0.05) percentage of β-hemolytic coliforms in fecal samples on days 2 and 5 PI, and greatest (P < 0.05) bacterial colonies in mesenteric lymph nodes on day 11 PI compared with pigs in the CON and REC groups. Pigs in TRA had the greatest (P < 0.05) neutrophils on day 5 PI and higher (P < 0.05) white blood cell counts and lymphocytes than other groups on day 11 PI. Pigs in TRA had the greatest (P < 0.05) serum C-reactive protein on days 2 and 5 PI and serum tumor necrosis factor-α on day 5 PI, compared with pigs in the CON and REC groups. Pigs fed REC had increased (P < 0.05) mRNA expression of zona occludens-1 (ZO-1) and occludin (OCDN) and reduced (P < 0.05) interleukin-1 beta (IL1B), interleukin-6 (IL6), and tumor necrosis factor-alpha (TNFA) in ileal mucosa on day 5 PI, compared with the CON, whereas TRA upregulated (P < 0.05) mRNA expression of IL1B, IL6, and cyclooxygenase-2 (COX2) in the ileal mucosa on day 11 PI, compared with the REC. In conclusion, trace amounts of antibiotic may exacerbate the detrimental effects of E. coli infection on pig performance by increasing diarrhea and systemic inflammation of weanling pigs.

Dietary copper/zinc-loaded montmorillonite improved growth performance and intestinal barrier and changed gut microbiota in weaned piglets

The effects of copper/zinc-loaded montmorillonite (Cu/Zn-Mt) on growth performance, intestinal barrier and gut microbiota of weaned pigs were investigated in the present study. A total of 108 piglets (Duroc × Landrace × Yorkshire; 6.36 kg; weaned at 21 ± 1 d age) were used in this experiment. The pigs were randomly assigned to three treatments with six replicates, six pigs in each replicate. The three treatments were as follows: (1) control group: basal diet; (2) Cu/Zn-Mt group: basal diet supplemented with 39 mg/kg Cu and 75 mg/kg Zn as Cu/Zn-Mt; and (3) Cu +Zn +Mt group: basal diet supplemented with the mixture of copper sulphate, zinc sulphate and montmorillonite (equivalent to the copper and zinc in the Cu/Zn-Mt treatment). The results indicated that, compared with the pigs from control group, average daily gain and gain: feed ratio were increased and the faecal score on days 7 and 14 after weaning was decreased by supplementation of Cu/Zn-Mt; intestinal transepithelial electrical resistance (TER) and expressions of tight junction protein claudin-1 and zonula occludens-1 were increased, and intestinal permeability of fluorescein isothiocyanate-dextran 4 kDa was decreased by supplementation with Cu/Zn-Mt. According to the Illumina-based sequencing results, Cu/Zn-Mt supplementation increased the relative abundance of core bacteria (Lactococcus, Bacillus) at genus level and decreased the potentially pathogenic bacteria (Streptococcus and Pseudomonas) in colon of weaned piglets. However, the piglets fed with the mixture of copper sulphate, zinc sulphate and montmorillonite showed no effects in above parameters in comparison with the pigs from control group. In conclusion, dietary Cu/Zn-Mt could improve growth performance, decrease the diarrhoea and improve intestinal barrier and bacterial communities of weaned pigs. The results indicated that 'loading' of montmorillonite with Zn and Cu changed not only its chemical but also its nutritional properties.

Dietary Glutamic Acid Modulates Immune Responses and Gut Health of Weaned Pigs

Simple Summary

Weaning stress can lead to intestinal barrier dysfunction, immune system destruction, and intestinal microbiota disruption, thereby reducing the absorption of nutrients and causing intestinal diseases. Glutamic acid is a non-essential amino acid that is abundantly present in the body and plays an essential function in cellular metabolism and immune responses. In this study, the effects of dietary glutamic acid on the growth performance, nutrient digestibility, immune responses, and intestinal health of weaned pigs were evaluated. Based on the results, dietary glutamic acid increased growth performance, nutrient digestibility, intestinal morphology, and ileal gene expression of tight junction proteins of weaned pigs and modified immune responses and gut microbiota. This study provides information to understand the functional use of dietary glutamic acid as a feed additive for improving the growth performance and intestinal health of weaned pigs.

Abstract

Dietary glutamic acid (GLU) is used as a feed additive because of its functional characteristics that may affect the growth performance and health of pigs. This study was carried out to determine the effects of dietary GLU on growth performance, nutrient digestibility, immune responses, and intestinal health of weaned pigs. A total of ninety-six weaned pigs (8.07 ± 1.17 kg of body weight; 28 days of age) were assigned to two dietary treatments (8 pigs/pen; 6 replicates/treatment) in a randomized complete block design (block: body weight): (1) a typical weaner diet (CON) and (2) CON supplemented with 0.5% GLU. The experimental period was for 4 weeks. All data and sample collections were performed at the specific time points during the experimental period. Pigs fed GLU had higher average daily gain and average daily feed intake for the first two weeks and nutrient digestibility than pigs fed CON. In addition, dietary GLU increased villus height to crypt depth ratio, number of goblet cells, and ileal gene expression of claudin family and occludin compared with CON, but decreased serum TNF-α and IL-6 and ileal gene expression of TNF-α. Moreover, pigs fed GLU had increased relative composition of bacterial communities of genus Prevotella and Anaerovibrio and decreased genus Clostridium and Terrisporobacter compared with those fed CON. This study suggests that dietary GLU influences growth performance and health of weaned pigs by modulating nutrient digestibility, intestinal morphology, ileal gene expression of tight junction proteins and cytokines, immune responses, and microbial community in the gut.

Effects of tea tree oil supplementation on growth performance, antioxidant capacity, immune status and microbial community in weaned pigs

The objective of this study was to determine whether dietary tea tree oil (TTO) supplementation could effectively replace the antibiotics through modulating the antioxidant capacity and intestinal microbiota profile, and then decreasing the diarrhoea incidence and improving the growth performance of weaned pigs. A total of 216 weaned pigs with initial body weights (BW) of 9.19 ± 1.86 kg were randomly allocated to three dietary treatments in a completely randomised design. The dietary treatments included a corn-soybean meal basal diet (CON) without any antibiotics, and two experimental diets formulated by adding 75 mg/kg aureomycin (AGP) or 100 mg/kg TTO into the basal diet, respectively. Pigs fed the TTO diet showed greater gain to feed ratio (p < 0.05) than those fed CON and AGP diets during d 0-14 and d 14-28. Both dietary TTO and AGP supplementation tended to increase the average daily gain of weaned pigs during d 14-28 (p = 0.06) and the overall 28-d period (p = 0.07), and significantly reduced (p < 0.05) the diarrhoea incidence during d 0-14 compared with the CON treatment. In addition, dietary TTO supplementation improved the apparent total tract digestibility of dry matter and ether extract (p < 0.05), and increased (p < 0.05) the propionate and butyrate concentrations in faecal samples of weaned pigs. Moreover, pigs fed the TTO diet showed greater total antioxidant capacity, greater superoxide dismutase and interleukin-10 concentrations, and lower malondialdehyde concentration in serum than those fed the CON diet (p < 0.05). Furthermore, pigs fed the TTO diet demonstrated greater relative abundance of Clostridiaceae_1, while those fed the AGP diet exhibited greater relative abundance of Lactobacillaceae at family level. In conclusion, dietary TTO supplementation could improve growth performance in weaned pigs, which could be mainly attributed to the benefits on nutrient digestibility, antioxidative capacity and microbial community profile.

Effects of Diet Supplemented with Excess Pyrroloquinoline Quinone Disodium on Growth Performance, Blood Parameters and Redox Status in Weaned Pigs

Simple Summary

Weaning is a vital process for weaned pigs since piglets are exposed to psychologic and environmental stresses. These stresses converge on the pig to cause low feed consumption and weight gain meanwhile increased risk of diarrhea and mortality during the early postweaning period. The use of antibiotic growth promoters to help prevent weaning stress in weaned pigs has been forbidden in the European Union, Korea, Japan and China. Pyrroloquinoline quinone disodium (PQQ·Na₂) is increasing interest in use of alternatives to in-feed antibiotics. In this study, we found PQQ·Na₂ can improve growth performance meanwhile improves antioxidant status of weaned pigs. A high oral dose of PQQ·Na₂ does not appear to have harmful effects on weaned pigs.

Abstract

The research was implemented to assess the safety of feeding excess of pyrroloquinoline quinone disodium (PQQ·Na₂) to 108 Duroc × Landrace × Large White weaned pigs (BW = 8.38 ± 0.47 kg). Pigs were weaned at 28 d and randomly distributed to one of three diets with six replicates and six pigs per replicate (three males and three females). Pigs in the control group were fed a corn-soybean meal-based diet (without growth promoter) while the two experimental diets were supplied with 7.5 and 75.0 mg/kg PQQ·Na₂, respectively. Average daily gain (ADG), average daily feed intake (ADFI), feed conversion (F:G), diarrhea incidence, hematology, serum biochemistry, organ index and general health were determined. Diets supplementation with 7.5 mg/kg PQQ·Na₂ in weaned pigs could increase ADG during the entire experimental period (p < 0.05). And there was a tendency to decrease F:G (p = 0.063). The F:G of weaned pigs fed 7.5 and 75.0 mg/kg PQQ·Na₂ supplemented diets was decreased by 9.83% and 8.67%, respectively, compared to the control group. Moreover, pigs had reduced diarrhea incidence (p < 0.01) when supplemented with PQQ·Na₂. No differences were observed between pigs supplemented with 0.0, 7.5 and 75.0 mg/kg PQQ·Na₂ diets on hematological and serum biochemical parameters as well as histological assessment of heart, liver, spleen, lung and kidney. At day 14, pigs had increased activity of glutathione peroxidase (GSH-Px) (p < 0.05), catalase (CAT) (p < 0.05) and total antioxidant capacity (T-AOC) (p < 0.05), and the serum concentration of malondialdehyde (MDA) was decreased (p < 0.01) with PQQ·Na₂ supplementation. At day 28, pigs had increased activities of total superoxide dismutase (T-SOD) (p < 0.01), GSH-Px (p < 0.01), CAT (p < 0.05) and T-AOC (p < 0.01), and serum concentration of MDA was lower (p < 0.01) with PQQ·Na₂ supplementation. In conclusion, PQQ·Na₂ can improve weaned pigs growth performance and serum antioxidant status. Meanwhile high PQQ·Na₂ inclusion of 75.0 mg/kg does not appear to result in harmful effects on growth performance of pigs.

coli and Supplemented with Carbadox or Bacillus subtilis

This study explored the metabolomic profiles in ileal mucosa and colon digesta in response to enterotoxigenic Escherichia coli F18 (ETEC) infection and dietary use of probiotics and low-dose antibiotics. Weaned pigs (n = 48, 6.17 ± 0.36 kg body weight) were randomly allotted to one of four treatments. Pigs in the negative control (NC) were fed a basal diet without ETEC challenge, whereas pigs in the positive control (PC), antibiotic, and probiotic groups were fed the basal diet, basal diet supplemented with 50 mg/kg of carbadox, or 500 mg/kg of Bacillus subtilis, respectively, and orally challenged with ETEC F18. All pigs were euthanized at day 21 post-inoculation to collect ileal mucosa and colon digesta for untargeted metabolomic profiling using gas chromatography coupled with time-of-flight mass spectrometry. Multivariate analysis highlighted a more distinct metabolomic profile of ileal mucosa metabolites in NC compared to the ETEC-challenged groups. The relative abundance of 19 metabolites from the ileal mucosa including polyamine, nucleotide, monosaccharides, fatty acids, and organic acids was significantly different between the NC and PC groups (q < 0.1). In colon digesta, differential metabolites including 2-monoolein, lactic acid, and maltose were reduced in the carbadox group compared with the probiotics group. In conclusion, several differential metabolites and metabolic pathways were identified in ileal mucosa, which may suggest an ongoing intestinal mucosal repair in the ileum of ETEC-challenged pigs on day 21 post-inoculation.

Growth performance, nutrient digestibility, and fecal microbial composition of weaned pigs fed multi-enzyme supplemented diets

A study determined the effects of supplementing corn-based diets for weaned pigs with multi-enzymes on growth performance, apparent total tract digestibility (ATTD) of nutrients, fecal score, and fecal microbial composition. A total of 132 pigs (initial body weight = 7.23 kg) that had been weaned at 21 d of age and fed a drug-free nursery diet for 7 d were housed in 33 pens of 4 barrows or gilts, blocked by body weight and gender, and fed 3 experimental diets at 11 pens per diet. The diets were corn-based diet without or with multi-enzyme A or B. Multi-enzyme A supplied 4,000 U of xylanase, 150 U of β-glucanase, 3,500 U of protease, and 1,500 U of amylase per kilogram of diet. Multi-enzyme B was the same as multi-enzyme A except that it supplied amylase at 150 U/kg, and that its source of amylase was different from that of multi-enzyme A. All diets contained phytase at 1,000 U/kg. The diets were fed for 35 d in 2 phases; phase 1 for the first 14 d and phase 2 for the last 21 d of the trial. Fecal score was determined daily during the first 7 d of the trial. Fecal samples were collected from rectum of 1 pig per pen on days 2, 7, 14, and 35 of the trial for determining bacterial composition. Also, fresh fecal samples were collected from each pen on days 41 and 42 to determine ATTD of nutrients. Multi-enzyme B increased (P < 0.05) average daily gain (ADG) for phases 1 and 2. For the overall study period, multi-enzyme B increased (P < 0.05) ADG from 262 to 313 g, and average daily feed intake (ADFI) from 419 to 504 g. Multi-enzyme A increased (P < 0.05) overall ADG from 262 to 290 g, but did not affect ADFI. Multi-enzyme A or B did not affect ATTD of gross energy, but increased (P < 0.05) the ATTD of ether extract from 30% to 36% or 37%, respectively. Multi-enzyme A did not affect fecal score; however, multi-enzyme B tended to decrease (P = 0.09) fecal score, implying that it tended to decrease diarrhea. Firmicutes were the most abundant phylum of fecal bacteria (its relative abundance ranged from 58% to 72%). Bacteroidetes and Actinobacteria were the 2nd and 3rd most abundant phyla of fecal bacteria. Neither multi-enzyme affected fecal bacterial composition. In conclusion, the addition of multi-enzyme A or B to phytase-supplemented corn-based diet for weaned pigs can improve their growth performance and fat digestibility. However, multi-enzyme B was more effective than multi-enzyme A in terms of improving the growth performance of weaned pigs fed corn-based diet.

Single-Blinded Study Highlighting the Differences between the Small Intestines of Neonatal and Weaned Piglets

Simple Summary

The gut mucosa of pigs, which contains intestinal epithelium and subepithelial immune cells, forms a barrier against microorganisms. Nonetheless, infectious diseases of the digestive tract remain the most frequent and recurrent conditions in the swine industry. Changes in intestinal morphology and structure primarily occur at birth and during weaning. However, the difference in the intestinal structures between neonatal and weaned piglets remains unclear. In this study, for the first time, we evaluated the differences in the small intestine between neonatal (0-day-old) and weaned piglets (21-day-old) and analyzed the morphology and immunological components of the small intestines of 0- and 21-day-old piglets, thereby providing preliminary data for future mechanistic studies.

Abstract

The gut is one of the body’s major immune structures, and the gut mucosa, which contains intestinal epithelium and subepithelial immune cells, is the primary site for eliciting local immune responses to foreign antigens. Intestinal immune system development in pigs is a transitional period during birth and weaning. This study compares the morphological and immunological differences in the small intestine of neonatal and weaned piglets to potentially prevent intestinal infectious diseases in neonatal piglets. Histological analyses of weaned piglet intestines showed increased crypt depth, higher IEL count, and larger ileal Peyer’s patches compared with those of neonates. Additionally, the ileal villi of weaned piglets were longer than those of neonatal piglets, and claudin-3 protein expression was significantly higher in weaned than in neonatal piglets. The numbers of CD3⁺ T, goblet, and secretory cells were also higher in the small intestines of weaned piglets than in those of neonates. No significant differences were observed in the secretory IgA-positive cell number in the jejunum of weaned and neonatal piglets. The mRNA expression of most pattern recognition receptors genes in the duodenum and jejunum was higher in the weaned than neonatal piglets; however, the opposite was true in the ileum. The mRNA levels of IL-1β and TNF-α in the jejunal and ileal mucosa were higher in weaned piglets than in neonatal piglets. There were significantly fewer CD3⁺, CD4⁺, and CD8⁺ T cells from peripheral blood-mononuclear cells in neonatal piglets. Our study provides insights regarding the different immune mechanisms within the small intestines of 0- and 21-day-old piglets. Studies on the additional developmental stages and how differences in the small intestines affect the response of pigs to pathogens remain warranted.

Effects of dietary supplementation of compound enzymes on performance, nutrient digestibility, serum antioxidant status, immunoglobulins, intestinal morphology and microbiota community in weaned pigs

The objective of this study was to evaluate the effects of compound enzymes (CE) (containing per g 375 U amylase, 2500 U protease, 4000 U xylanase and 150 U β-glucanase) on performance, nutrient digestibility, serum antioxidant status, immunoglobulins, intestinal morphology, volatile fatty acids contents and microbiota community in weaned pigs. Seventy-two pigs (Duroc × Landrace × Yorkshire, weaned at d 28) with an average body weight of 8.49 ± 0.87 kg were allotted into two treatments with six replicate pens per treatment (three barrows and three gilts per pen) according to sex and body weight in a randomised complete block design. The treatments contained a corn-soybean meal-barley basal diet (CON) or a basal diet supplemented with 1000 mg CE/kg (CE). The study was divided into phase 1 (d 1 to 14) and 2 (d 15 to 35). The average daily gain was increased (p < 0.05) in pigs fed CE in phase 2 and overall (d 1 to 35) compared with CON. These pigs had greater (p ≤ 0.05) serum IgA, IgG, superoxide dismutase and catalase contents, as well as tended to increase serum IgM content and apparent total tract digestibility (ATTD) of organic matter in phase 1 compared with CON. In phase 2, pigs supplemented with CE showed greater (p < 0.01) ATTD of dry matter, organic matter, crude protein and gross energy compared with CON. These pigs also had increased (p < 0.05) IgA, IgG, IgM, superoxide dismutase contents, and decreased (p < 0.05) malondialdehyde content in serum compared with CON. Moreover, pigs fed CE had higher (p < 0.05) villus height and villus height to crypt depth ratio in ileum, and tended to increased acetic acid content in colon compared with CON. Furthermore, pigs fed CE had increased (p < 0.05) relative abundance of Firmicutes at phylum level, Lactobacillales at order level, Lactobacillaceae at family level, Bacilli at class level, Lactobacillus at genus level in caecum and colon, as well as lower (p < 0.05) relative abundance of Bacteroidetes at phylum level, Bacteroidales at the order level, Bacteroidia at class level, Clostridium_sensu_stricto_6 at genus level in colon compared with CON. In conclusion, dietary inclusion of compound enzymes could effectively improve nutrient digestibility, serum antioxidant status, immunoglobulin, gut morphology, microbiota community, and therefore improve performance in weaned pigs.

Effect of Spent Mushroom (Cordyceps militaris) on Growth Performance, Immunity, and Intestinal Microflora in Weaning Pigs

There are limited published reports regarding the optimal dosage of spent mushroom. This study investigated the effect of various levels of spent mushroom derived from C. militaris as an alternative growth promoter to an in-feed antibiotic on the growth performance, blood profiles, immunoglobulin, inflammation, and microbial count of weaning pigs. A total of 120 pigs (6.63 ± 0.13 kg initial body weight) were blocked by weight and sex in a randomized complete block design. Each treatment had six replicates of four pigs each. The pigs were allotted into five treatments: (1) positive control (PC) with 150 mg/kg colistin; (2) negative control (NC) without antibiotic inclusion; and (3-5) negative control groups with 0.5, 1.0, and 1.5 g/kg of C. militariss pent mushroom (SM), respectively. Blood samples were collected at day 35 for determination of blood-related lipid metabolism and immunity. Fresh fecal samples were collected to examine microbial counts on day 35 postweaning. The results showed that SM at 1.5 g/kg improved the body weight, average daily weight gain, and average daily feed intake of weaning pigs in the overall period (p < 0.05). Moreover, the highest dosage of SM caused improvements in the concentrations of high-density lipoprotein, and immunoglobulin A, along with suppressions of total cholesterol, interleukin-1, tumor necrosis factor-α, and E. coli (p < 0.05). Therefore, the weaned pigs fed a 1.5 g/kg SM diet showed improved growth performance and displayed greater immunoglobulin secretion and lower inflammation, pathogenic population, and cholesterol concentration.

coli

There is growing evidence to support the beneficial effects of supplementing direct-fed microbials (DFM) on performance, health status, and immune responses of weaned pigs. Therefore, the objective of this study was to investigate dietary supplementation of Bacillus subtilis (DSM 25841) on growth performance, diarrhea, gut permeability, immunity and metabolomic profiles of weaned pigs experimentally infected with a pathogenic F18 Escherichia coli (E. coli). E. coli infection reduced (P < 0.05) growth performance and intestinal villi height, whereas increased (P < 0.05) diarrhea and permeability in the jejunum compared with non-challenged control. Supplementation of Bacillus subtilis linearly enhanced average daily gain of E. coli infected pigs (d 0 to 5 post-inoculation (PI), P < 0.05; d 0 to 11 PI, P = 0.058). Inclusion of high dose Bacillus subtilis reduced (P < 0.05) jejunal permeability on d 5 and d 11 PI compared with the E. coli challenged control. E. coli challenged control pigs up-regulated (P < 0.05) the mRNA expression of SLC5A10 and MUC2 on d 5 PI, but down-regulated (P < 0.05) expression of SLC5A10, MUC2, and CLDN1 on d 11 PI in jejunal mucosa. Supplementation of Bacillus subtilis linearly up-regulated (P < 0.05) the mRNA expression of CFTR and ZO1 on d 5 PI and SLC5A10 and MUC2 on d 11 PI in jejunal mucosa of E. coli infected pigs. E. coli infection increased (P < 0.05) the mRNA expression of several immune genes in the ileal mucosa, while inclusion of Bacillus subtilis linearly down-regulated gene expression of IL1A on d 5 PI (P = 0.07) and IL6 on d 11 PI (P < 0.05) in ileal mucosa of E. coli infected pigs. Supplementation of Bacillus subtilis modified (Fold change > 1.5; FDR < 0.20) metabolomic profiles in colon digesta, related to pathogenesis and amino acid metabolism. In conclusion, supplementation of Bacillus subtilis enhanced growth rate, improved gut health, and modified metabolomic profiles of weaned pigs experimentally infected with a pathogenic E. coli.

Bacillus subtilis: a potential growth promoter in weaned pigs in comparison to carbadox

The study was conducted to investigate the efficacy of a probiotic Bacillus subtilis strain on growth performance, diarrhea, systemic immunity, and intestinal health of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli and to compare the efficacy of B. subtilis with that of carbadox. Weaned pigs (n = 48, 6.17 ± 0.36 kg body weight [BW]) were individually housed in disease containment rooms and randomly allotted to one of four dietary treatments: negative control (NC, control diet without E. coli challenge), positive control (PC, control diet with E. coli challenge), and supplementation of 50 mg/kg of carbadox (antibiotic growth promotor [AGP]) or 2.56 × 109 CFU/kg of B. subtilis probiotics (PRO). The experiment lasted for 28 d with 7 d before and 21 d after the first E. coli inoculation. Fecal and blood samples were collected on days 0, 3, 7, 14, and 21 post inoculation (PI) to analyze β-hemolytic coliforms and complete blood cell count, respectively. Diarrhea score was recorded daily for each pig to calculate the frequency of diarrhea. All pigs were euthanized at day 21 PI to collect jejunal and ileal mucosa for gene expression analysis. Pigs in AGP had greater (P < 0.05) BW on days 7, 14, and 21 PI than pigs in PC and PRO groups. Supplementation of PRO enhanced pigs' BW on day 21 PI compared with the PC. Escherichia coli F18 challenge reduced (P < 0.05) average daily gain (ADG) and feed efficiency from day 0 to 21 PI, while supplementation of carbadox or PRO enhanced ADG and feed efficiency in E. coli F18-challenged pigs from day 0 to 21 PI. Pigs in AGP and PRO groups had reduced (P < 0.05) frequency of diarrhea throughout the experiment and fecal β-hemolytic coliforms on day 7 PI than pigs in the PC. Pigs in PRO had greater (P < 0.05) gene expression of CLDN1 in jejunal mucosa than pigs in the PC. Supplementation of carbadox or PRO reduced (P < 0.05) the gene expression of IL6 and PTGS2 in ileal mucosa of E. coli-infected pigs compared with pigs in the PC. Pigs in the PRO group had lower (P < 0.05) white blood cell number and neutrophil count, and serum haptoglobin concentration on day 7 PI, and less (P < 0.05) monocyte count on day 14 PI, compared with PC. In conclusion, supplementation of probiotic B. subtilis could enhance disease resistance and promote the growth performance of weaned pigs under disease challenge conditions. The potential mechanisms include but not limited to enhanced gut barrier integrity and local and systemic immune responses of weaned pigs.

Effects of copper and zinc sources and inclusion levels of copper on weanling pig performance and intestinal microbiota

A 42-d experiment was conducted to evaluate the effect of Cu and Zn source and Cu level on pig performance, mineral status, bacterial modulation, and the presence of antimicrobial-resistant genes in isolates of Enterococcus spp. At weaning, 528 pigs (5.9 ± 0.50 kg) were allotted to 48 pens of a randomized complete block design in a 2 × 2 factorial arrangement with two Cu and Zn sources (SF: sulfate and HCl: hydroxychloride) and two Cu levels (15 and 160 mg/kg). As a challenge, the pigs were reared in dirty pens used by a previous commercial batch. Two-phase diets were offered: the pre-starter (PS) phase from day 1 to 14 and the starter phase (ST) from day 14 to 42. At days 14 and 42, pigs were individually weighed and blood samples from one pig per pen were taken. At the end of the experiment, one pig per pen was euthanized to collect the samples. Feeding high levels of Cu increased body weight (BW) from 16.6 to 17.7 kg (P < 0.001). Furthermore, average daily gain, gain to feed (G:F) ratio, average daily feed intake (ADFI), and mineral status were enhanced with Cu at 160 mg/kg (P < 0.05) compared with Cu at 15 mg/kg. There was no effect of the interaction between source × level on any of the growth performance responses except for ADFI (P = 0.004) and G:F (P = 0.029) at the end of the ST period and for G:F (P = 0.006) for entire nursery period (day 0 to 42). At the end of the ST period, pigs fed Cu at 160 mg/kg as HCl had not only higher ADFI but also lower G:F than those fed Cu as SF at 160 mg/kg. Meanwhile, for the entire nursery period, G:F did not differ between pigs fed Cu at 160 mg/kg as HCl or SF. In colonic digesta, the relative abundance of Streptococcus, Enterobacter, Escherichia, among others, decreased (P-adjust < 0.05), while Lachnospira and Roseburia tended (P-adjust < 0.10) to increase in pigs fed Cu at 160 mg/kg as HCl compared with those fed Cu SF at 160 mg/kg. An increase (P-adjust < 0.05) in Methanosphaera and Roseburia was observed in pigs fed Cu at 160 mg/kg. From colon digesta, Enterococcus spp. was isolated in 40 samples, being E. faecalis the most dominating (65%) regardless of the experimental diet. Genes of ermB (7.5%) and tetM (5%) were identified. No genes for Cu (tcrB) or vancomycin (vanA, vanB, vanC1, and vanC2) were detected. In conclusion, European Union permissible levels of Cu (160 mg/kg), of both sources, were able to increase performance, mineral status, and bacterial modulation compared with nutritional level. Different effects on growth performance, mineral tissue content, and microbial modulation were observed between Cu and Zn sources.

The Optimal Combination of Dietary Starch, Non-Starch Polysaccharides, and Mannan-Oligosaccharide Increases the Growth Performance and Improves Butyrate-Producing Bacteria of Weaned Pigs

Simple Summary

Information about the optimal carbohydrate combination for pigs is scarce. This present study explored the effects of different combinations of starch, non-starch polysaccharides, and mannan-oligosaccharide on the growth performance, nutrient digestibility, and microbial communities in weaned pigs, which contributed a novel way of evaluating the carbohydrate quality of the diet for pigs.

Abstract

The present experiment was conducted to dissect the effects of different carbohydrate combinations on the growth performance, nutrient digestibility, and microbial communities in weaned pigs. The combination was optimized by constructing L₉(3⁴) orthogonal design. Three factors include starch (amylose to amylopectin (AM/AP) ratio 2:1, 1:1, 1:2), non-starch polysaccharides (NSP) (1%, 2%, 3%, a mixture of inulin with cellulose by 1:1), and mannan-oligosaccharide (MOS) (400, 800, 1200 mg/kg) were investigated and nine combinations were implemented under different levels of these factors. One hundred and sixty-two weaned pigs were randomly assigned to nine dietary treatments with six replicates per treatment and three pigs per replicate. Results exhibited that different combinations of starch, NSP, and MOS affected the gain to feed (G:F) (p < 0.05), diarrhea incidence (p < 0.10), nutrient digestibility (p < 0.05), microbial communities, and short-chain fatty acid (SCFA) concentrations (p < 0.05). In the present study, taking into account three-way ANOVA, range, and direct analysis, we found that the optimal carbohydrate combination was starch AM/AP 1:1, NSP 3%, MOS 400 mg/kg for weaned pigs. Moreover, feeding this combination diet could promote the growth performance and nutrient digestibility, increase the butyrate-producing bacteria, and to some extent improve lipid metabolism. This study provided a novel way to evaluate the carbohydrate quality in swine production.

Thermomechanical and enzyme-facilitated processing of soybean meal enhanced in vitro kinetics of protein digestion and protein and amino acid digestibility in weaned pigs

Soybean meal (SBM) contains anti-nutritional factors (ANF) that may limit kinetics and total extent of protein digestion in pigs. This study evaluated the effects of thermomechanical and enzyme-facilitated (TE) processing on in vitro kinetics of crude protein (CP) digestion and CP and amino acid (AA) digestibility in weaned pigs. Each batch of SBM (48% CP) was divided into two parts: non-processed SBM as control vs. thermomechanical and enzyme-facilitated processed soybean meal (TES) as the experimental group. For digestion kinetics, samples (three batches of non-processed SBM vs. TES) were incubated in triplicate sequentially with pepsin at pH 3.5 for 1.5 h (stomach phase) and subsequently with pancreatin and bile extract at pH 6.8 for 0, 0.5, 1, 2, 4, or 6 h (small intestine phase). Protein was classified into CPfast, CPslow, and CPresistant corresponding to CP digested within the first 0.5 h, from 0.5 to 4 h, and after 4 h plus undigested CP, respectively. Eight weaned barrows (Large White × Duroc, 9.43 ± 0.40 kg) were surgically fitted with a T-cannula at the terminal ileum. Pigs were randomly assigned to a Youden square with three diets over four periods. The three diets were an N-free diet and two diets using 40% SBM or TES as the sole source of AA with Cr2O3 as an indigestible marker. Each period included sequentially a 5-d adaptation, 2-d collection of feces, and 2-d collection of ileal digesta. The TE processing reduced ANF content in TES by 91% for lectin, 22% for trypsin inhibitor activity, 75% for β-conglycinin, and 62% for glycinin compared with SBM. In vitro, TE processing increased (P < 0.05) digested CP by 5.6% and enhanced the kinetics of CP digestion by tending to increase (P = 0.056) CPfast by 25% and reducing (P < 0.05) CPslow and CPresistant by 48% and 11%, respectively. In pigs, TE processing increased (P < 0.05) apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of CP in TES by 2.3% and 2.1%, respectively. The TE processing increased (P < 0.05) AID and SID of all AA up to 3.3%, except for AID of Pro and SID of Pro, Gly, and Cys. The TE processing did not change reactive Lys or Lys:CP but increased (P < 0.05) SID of Lys and reactive Lys by 3%. Combined, the greater in vitro digestion kinetics matched the greater in vivo AID and SID of CP in TES and lower ANF compared with SBM. Thus, TE processing created a protein source that is digested faster and to a greater extent than SBM, thereby lowering the chance of protein fermentation.

Dietary supplementation of plant essential oil improves growth performance, intestinal morphology and health in weaned pigs

The present study was conducted to explore the effect of plant essential oil (PEO) on growth performance, intestinal morphology and health in weaned pigs. Twenty-four weaned pigs were assigned into four groups fed with a basal diet (CON) or basal diet containing PEO at a concentration of 50 (PEO50), 100 (PEO100) or 200 ppm (PEO200). After 21 days, pigs were slaughtered and blood and tissue samples were collected. Result showed that PEO200 group significantly increased the average daily gain (ADG) compared with CON group (p < .05). Moreover, PEO supplementation significantly improved the digestibility of DM (p < .05). However, it significantly decreased the serum triglyceride and cholesterol concentration (p < .05). Interestingly, PEO supplementation significantly increased the activity of sucrase in the duodenal and the activity of lactase in the jejunal mucosa (p < .05). Moreover, PEO supplementation improved the growth of intestinal mucosa. As compared to the CON group, the jejunum and ileum villus height were significantly elevated in the PEO200 group (p < .05). Importantly, the expression levels of critical genes associated with nutrient transportation (i.e., GLUT2 and SGLT1) and barrier function (occludin) were significantly elevated in the PEO200 group (p < .05). Moreover, the PEO100 and PEO200 group had higher propionic acid concentration and higher total bacterial gene copies in colon digesta than the CON group (p < .05) respectively. These results not only suggest that PEO has a positive role in the regulation of growth and intestinal health in weaned pigs, but also offer a potential candidate substituting the conventionally used antibiotics in the livestock industry.

The effects of a temporary lysine restriction in newly weaned pigs on growth performance and body composition1

A serial slaughter study was conducted to determine the effects of a temporary Lys restriction immediately following weaning on growth performance and body composition. One hundred forty-four Yorkshire × Landrace × Duroc pigs (initial BW: 6.9 ± 0.2 kg) were randomly allocated to one of three dietary treatments (six pens per treatment with eight pigs per pen; four barrows and four gilts). For a 3-wk restriction period, pigs were fed diets that were 110% (Control) of the estimated required standardized ileal digestible (SID) Lys for nursery pigs or 20% (Lys20) or 40% (Lys40) below the estimated required SID Lys. Thereafter, all pigs were fed a common grower diet containing 120% of the estimated required SID Lys for 6 wk (recovery period). During the restriction period, ADG and G:F decreased with decreasing dietary Lys concentration (linear; P < 0.01). At the end of the restriction period, BW and whole-body protein concentrations decreased (linear; P < 0.01) and carcass lipid concentrations increased (linear; P < 0.01) with decreasing dietary Lys concentration. During the first 3 wk of the recovery period, ADG and G:F increased (linear; P < 0.05 and P < 0.01, respectively) and whole-body protein concentration at week 3 of the recovery period decreased (linear; P < 0.01) with decreasing dietary Lys concentration. There were no dietary treatment differences in whole-body lipid concentration after 3 wk of the recovery period. During the second half of the recovery period (weeks 7 through 9), there were no differences in ADG or G:F; after week 6, there were no differences in final BW (50.3 ± 0.5 kg) or whole-body protein (16.9 ± 0.2%) or lipid (14.9 ± 0.7%) concentrations. In conclusion, newly weaned pigs previously fed a Lys-limiting diet for 3 wk immediately after weaning achieved full compensatory growth with no differences in BW or body composition after a 6-wk recovery period. Reducing dietary Lys concentration early after weaning is a potential means to reduce the cost of (early) nursery diets without impacting overall growth and carcass composition.

Effect of fibre sources on performance, serum parameters, intestinal morphology, digestive enzyme activities and microbiota in weaned pigs

This study was conducted to evaluate the effects of wheat bran (WB) as insoluble fibre source, and sugar beet pulp (SBP) as soluble fibre source, on performance, serum parameters and intestinal health in weaned pigs. A total of 90 weaned pigs (BW: 7.33 ± 1.24 kg) were randomly assigned to three dietary treatments: (1) a control diet (CON) based on corn and soybean meal; (2) CON + 6% WB; (3) CON + 6% SBP. Each treatment had five replicate pens with six pigs per pen. The experimental period was divided into two phases (d 0 to 14 and d 14 to 28). Pigs in group WB tended to have greater avarage daily gain than those in group SBP. Compared with CON, SBP reduced (p < 0.05) the apparent total tract digestibility (ATTD) of dry matter, organic matter (OM), gross energy and neutral detergent fibre on d 14 and 28, while WB decreased (p < 0.05) the ATTD of OM on d 28. Pigs in group SBP had higher (p < 0.05) glucagon-like peptide 1 concentration than the other groups on d 14 and 28. The villus height to crypt depth (V:C) ratio of duodenum and jejunum in pigs fed diet WB were greater (p < 0.05) than in group SBP. The WB increased (p < 0.05) the V:C ratio of ileum compared with CON or SBP. Compared with SBP, WB increased (p < 0.05) the sucrase activity in the duodenum. Moreover, pigs in WB had higher (p < 0.05) activities of maltase and sucrase in the jejunum compared with CON or SBP. The abundances of Ruminococcaceae and Prevotellaceae were increased (p < 0.05) in WB, while the Lachnospiraceae abundance was increased (p < 0.05) in SBP. WB increased (p < 0.05) concentrations of acetate, butyrate and total short-chain fatty acids (SCFA), while SBP increased (p < 0.05) concentrations of acetate and total SCFA when compared with CON. In conclusion, WB was beneficial to performance in weaned pigs by improving morphology, enzyme activities and microbiota when compared with SBP, highlighting that effects of fibre depends on the fibre sources.

Essential Oil Blend Could Decrease Diarrhea Prevalence by Improving Antioxidative Capability for Weaned Pigs

Simple Summary

Antibiotics have been applied as growth promoters in swine production for many years. Due to increased concern about drug resistance, there is an urgent need to find alternatives to antibiotics for animal production. Present research indicates that essential oils have a beneficial influence on animal nutrition and production due to the antimicrobial and antioxidant properties. Dietary essential oil supplementation could be an alternative to antibiotics for improving swine production and decreasing diarrhea prevalence during the weaning period.

Abstract

Finding an alternative to in-feed antibiotics is important because of increasing contemporary concern regarding drug residues and the development of drug-resistant bacteria. The purpose of this study was to test the hypothesis that essential oils added to the feed would decrease diarrhea prevalence in post-weaned pigs. Ninety weaned piglets (initial body weight (BW): 8.1 ± 1.4 kg) were randomly assigned to one of three dietary diets: (1) a control diet (CON, the basal diet without antibiotics), (2) an antibiotic diet (AB, CON supplemented with colistin sulfate, 20 mg/kg and bacitracin zinc, 40 mg/kg), or (3) an essential oil diet (EO, CON supplemented with an essential oil blend 100 mg/kg) in a completely randomized block design for a 28-day period. The results revealed that AB and EO improved the average daily gain of the piglets from day (d) 15 to 28 (p < 0.05). The diarrhea prevalence in piglets fed AB and EO was lower than that of piglets fed CON (p < 0.05). There was no significant difference in the growth performance or diarrhea prevalence between the AB and EO treatments. Nutrient digestibility was measured at d 28. Compared with CON, EO increased the apparent total tract digestibility of gross energy and crude protein (p < 0.05). Villus height in the duodenum and the ratio of villus height to crypt depth in the jejunum for piglets fed AB and EO was greater than those for piglets fed CON (p < 0.05). The essential oil blend improved the superoxide dismutase (SOD) and catalase (CAT) activities and total antioxidant capacity (T-AOC), but decreased the 8-hydroxy deoxyguanosine content in serum on d 14 (p < 0.05). Decreased malondialdehyde (MDA) and protein carbonyl content were observed on d 28 in comparison with CON (p < 0.05). The mucosa in the jejunum of pigs fed EO had greater T-AOC, SOD levels, and glutathione peroxidase (GSH-Px) activities than that of pigs fed CON (p < 0.05). Pigs fed EO and AB had greater GSH-Px activity in the liver tissue than pigs fed CON (p < 0.05). Not only did jejunal and ileal mucosa have EO upregulated SOD1 mRNA expression (p < 0.05), this was also the case in liver tissue. GPx1 expression in the ileal mucosa and GPx4 expression in the liver tissue were higher for pigs fed EO when compared to those fed CON (p < 0.05). Collectively, a dietary essential oil blend supplementation, which has natural antimicrobial properties, could enhance growth performance and decrease diarrhea prevalence in weaned pigs through increases in antioxidative capacity.

Effects of super-dosing phytase and inositol on growth performance and blood metabolites of weaned pigs housed under commercial conditions1

A total of 2,156 weaned pigs (6.75 ± 0.11 kg BW) were used in a 42-d study to evaluate whether improvements in growth performance associated with super-dosing phytase can be explained by the complete dephosphorylation of phytate and liberation of inositol. Two phytase doses (0 and 2,500 FTU/kg) and 3 inositol concentrations (0%, 0.15%, and 0.30%) were combined to create 6 dietary treatments in a 2 × 3 factorial arrangement. Pigs were fed a 3-phase feeding program, with periods being 10, 10, and 22 d, respectively. Blood samples were collected on days 0, 21, and 42 from a subset of 48 pigs to analyze mineral and myo-inositol concentrations. During Phase 1, super-dosing phytase tended to improve ADG compared with pigs fed diets without phytase (P = 0.09). Increasing concentrations of inositol improved the efficiency of gain in pigs fed diets without phytase (1,022.1, 1,040.9, and 1,089.2 g/kg), but not diets with phytase (1,102.2, 1,087.2, and 1,076.2 g/kg), and this improvement was equivalent to that observed with super-dosing phytase in the absence of inositol (interaction, P = 0.015). During Phase 2, super-dosing phytase improved ADG (P = 0.001), resulting in heavier BW (P = 0.007). During Phase 3 and overall, inositol supplementation increased ADG and ADFI in a quadratic manner (P < 0.10), with the highest ADG and ADFI observed for pigs fed 0.15% of inositol. Super-dosing phytase increased serum Zn on day 21, but not on day 42 (interaction, P = 0.008), increased serum Cu (P = 0.01), but decreased serum Fe (P = 0.02). Plasma myo-inositol increased linearly from 66.9 to 97.1 and 113.2 nmol/mL with increasing inositol (P < 0.001). When plasma myo-inositol was analyzed within the subgroup of pigs fed diets without added inositol, super-dosing phytase increased plasma myo-inositol from 57.81 to 76.05 nmol/mL (0 and 2,500 FTU/kg, respectively; P = 0.05). Results demonstrate that exogenous inositol improved efficiency of gain in weaned pigs to the same level as that observed with super-dosing phytase, but this occurred only during the first 10 d of the nursery period. This suggests that the improvement in efficiency of growth when applying super-dosing phytase could be linked, in part, to complete dephosphorylation of phytate and liberation of myo-inositol, and that myo-inositol had a greater metabolic impact in piglets immediately after weaning. Consequently, myo-inositol may be a conditionally essential nutrient for young pigs during weaning stress, but further research is needed to prove this hypothesis.

The Effect of Dietary Quercetin on the Glutathione Redox System and Small Intestinal Functionality of Weaned Piglets

Quercetin has been shown to alleviate mucosal damage and modulate the glutathione (GSH) redox system in the colon of rodents. In the current study, we assessed whether quercetin was able to mitigate small intestinal dysfunction in weaned pigs. Here, 224 weaned piglets were fed a diet containing quercetin at either 0, 100, 300, or 900 mg/kg diet until d14 post-weaning, followed by a common basal diet until d42. Eight animals per treatment were sampled at d5 and d14 post-weaning. In these animals, the small intestinal histomorphology, barrier function, and protein abundance of occludin, caspase-3, and proliferating cell nuclear antigen were assessed. None of these parameters were affected, and neither did quercetin improve performance up to d42 post-weaning. The GSH redox system was evaluated in blood, small intestinal mucosa, and liver. Quercetin did not affect the glutathione peroxidase, glutathione reductase, and glutamate–cysteine ligase activity in these tissues. In contrast, the hepatic glutathione transferase (GST) activity was significantly increased by quercetin supplementation at d5 post-weaning of 100, 300, and 900 mg/kg. Importantly, d5 was characterized by a more oxidized GSH redox status. To conclude, dietary quercetin had little effect on the small intestine, but did upregulate hepatic GST in the occurrence of redox disturbance.