Effect of maternal seaweed extract supplementation on suckling piglet growth, humoral immunity, selected microflora, and immune response after an ex vivo lipopolysaccharide challenge

Preweaning Purified Fucoidan Drench: Effects on Growth, Immune Response, and Intestinal Morphology in Weaned Piglets

Weaning stress imposes considerable physiological challenges on piglets, often manifesting in intestinal disturbances, such as inflammation and compromised barrier function, ultimately affecting growth and health outcomes. While conventional interventions, including antimicrobials, have effectively mitigated these sequelae, concerns surrounding antimicrobial resistance necessitate the exploration of alternatives. Fucoidan, derived from brown seaweed, offers promise due to its antioxidant and anti-inflammatory effects. Previous research has been limited to the in-feed supplementation of partially purified fucoidan extracted from brown seaweed. The focus of the present study is assessing the effect of a preweaning drench with highly purified (85%) fucoidan on piglet growth, immune response, and intestinal morphology post-weaning. Forty-eight male piglets at 17 ± 3 days of age (5.67 ± 0.16 kg) were assigned to a saline (control), fucoidan, or antimicrobial group, receiving treatment as a single 18 mL oral drench three days before weaning. Monitoring for seven days post-weaning included body weight measurements, blood sample collection for the inflammatory protein assay, and small intestine morphological analysis. The findings revealed that the preweaning fucoidan drench did not elicit adverse effects on piglets. However, neither fucoidan nor antimicrobial drenches significantly enhanced growth parameters, immune markers, or intestinal morphology compared to that of the control-treated piglets (p > 0.05). The lack of response may be attributed to the high health status of the experimental cohort and the limitation of a single dosage. Future research should consider a more challenging production setting to evaluate the viability and optimal application of fucoidan as an antimicrobial alternative in the pig industry.

Laminaria japonica Polysaccharides Improves the Growth Performance and Faecal Digestive Enzyme Activity of Weaned Piglets

The aim of this experiment was to investigate the effect of Laminaria japonica polysaccharide (LJP) supplementation at levels of 100, 200, or 400 mg/kg on the growth performance, faecal digestive enzyme activity, and serum biochemistry and amino acids of weaned piglets. One hundred and twenty weaned piglets (Barkshire × Licha Black, 21 days old, 6.13 ± 0.16 kg) were randomly divided into four groups with five replicates of six piglets in each group based on body weight. Piglets were fed with different levels (0, 100, 200, and 400 mg/kg) of LJP for a 21-day trial. On day 21, faecal and blood samples were collected from one piglet per pen. The results showed that the supplementation of the 200 and 400 mg/kg LJP significantly increased average daily gain (ADG) and average daily feed intake (ADFI) compared to the control group (p = 0.007; p = 0.002), and dietary LJP linearly increased ADG and ADFI (p = 0.002; p < 0.001). In addition, the supplementation of the 200 and 400 mg/kg LJP significantly increased faecal amylase activity (p < 0.001) compared to the control group, and dietary LJP linearly increased faecal amylase and lipase activities (p = 0.001; p = 0.037). Moreover, dietary LJP at 400 mg/kg increased serum histidine content compared to the other groups (p = 0.002), and dietary LJP linearly increased the contents of serum histidine and asparagine in piglets (p < 0.001; p = 0.046). In conclusion, supplementation of 200 and 400 mg/kg LJP could enhance growth performance and faecal digestive enzyme activity and modulate the serum amino acid content of weaned piglets, potentially contributing to the health of weaned piglets.

Nutritional Strategies to Mitigate Post-Weaning Challenges in Pigs: A Focus on Glucans, Vitamin D, and Selenium

This review examines the challenges faced by the pig industry, with a specific focus on improving the health and growth of weaned pigs. It emphasizes the immediate necessity of investigating alternative approaches to managing pig nutrition and health due to restrictions on the use of antibiotics and the prohibition of zinc oxide in weaned pig diets. The weaning phase is identified as a critical stage in piglet development, characterized by stressors that affect their gastrointestinal health, immune responses, and overall physiology. The primary challenge during weaning arises from transitioning piglets from a digestible milk-based diet to a less digestible cereal-based feed, causing nutritional stress. This manifests as reduced feed intake, leading to gastrointestinal disturbances, intestinal inflammation, and adverse effects on intestinal structure and microbiota. To address these challenges and optimize piglet development, various nutritional strategies have been explored. Notably, glucans, particularly β-glucans from fungi, cereals, algae, and yeast, show promise in alleviating weaning-related issues. Furthermore, it is important to highlight the critical roles played by Vitamin D and selenium in piglet nutrition. These essential nutrients can be sourced naturally from enriched mushrooms that are specifically enriched with Vitamin D and selenium, providing a sustainable dietary option. In conclusion, effective nutritional strategies, including glucans, Vitamin D, selenium, and enriched mushrooms, are beneficial for addressing weaning-related challenges.

Effects of algal supplementation in feed to broiler breeders on transfer of nutrients and antibodies to chicks and quality of hatchlings

Breeder nutrition is an important factor for chick quality since the chick embryo relies on nutrients available in the egg for growth and development. In addition, the egg is providing the chick with important antibodies that are vital during the first weeks of life. Brown algae contains several bioactive compounds, and dietary supplementation with algal extracts have shown improved gut health and immune responses in both pigs and poultry. The aim of this study was to investigate if feeding the brown algae Saccharina latissima, intact or as an extract, to broiler breeders can affect breeder hens' antibody responses to vaccination, egg quality and transfer of antibodies and nutrients to the egg and thereby improve the quality of newly hatched chicks. Forty-five hens and nine roosters of the parent lines of the fast-growing broiler Ross 308 were included in the experiment where hens were 31 weeks at the start. The hens were housed individually and fed one of three dietary treatments for seven weeks; (a) control, (b) addition of 0.6% algal meal or (c) addition of 0.08% algal extract. The hens were given a booster vaccination against infectious bronchitis virus (IBV) 21 days after the start of experiment. During experimental days 32-42, hens were naturally mated every 5th day and hatching eggs were collected. A total of 255 chicks were hatched, and chick quality was assessed. Moreover, on chick day three, blood was collected from 48 focal chickens and total immunoglobulin Y levels and specific titres to IBV in serum were determined. The results showed that feeding the brown algae Saccharina latissima, intact or as an extract to broiler breeders did not affect egg production, egg quality, antibody responses to vaccination or transfer of antibodies from hen to chick. However, feeding intact algae significantly increased the levels of iodine and decreased the level of selenium in the eggs and resulted in a lower proportion of chicks with maximum quality score. Interestingly, algal feeding, both intact and as an extract, increased the abdominal fat pad in broiler breeders by about 17% without affecting BW. In conclusion, supplementation of broiler breeder diets with algal extract from Saccharina latissima, but not intact algal meal is a promising dietary strategy to increase the abdominal fat pad without causing any adverse effects on nutrient level in eggs or chick quality.

Comparison of the Effects of Enzymolysis Seaweed Powder and Saccharomyces boulardii on Intestinal Health and Microbiota Composition in Kittens

Kittens are prone to intestinal health problems as their intestines are not completely developed. Seaweed is rich in plant polysaccharides and bioactive substances that are highly beneficial to gut health. However, the effects of seaweed on cat gut health have not been assessed. This study compared the effects of dietary supplementation with enzymolysis seaweed powder and Saccharomyces boulardii on the intestinal health of kittens. In total, 30 Ragdoll kittens (age: 6 months; weight: 1.50 ± 0.29 kg) were assigned to three treatment groups for a 4-week feeding trial. The dietary treatment given was as follows: (1) basal diet (CON); (2) CON + enzymolysis seaweed powder (20 g/kg of feed) mixed evenly with the diet (SE); and (3) CON + Saccharomyces boulardii (2 × 10¹⁰ CFU/kg of feed) mixed evenly with the diet (SB). Compared with the CON and SB groups, dietary supplementation with the enzymolysis seaweed powder improved the immune and antioxidant capacity and also reduced the intestinal permeability and inflammation levels of kittens. The relative abundance of Bacteroidetes, Lachnospiraceae, Prevotellaceae, and Faecalibacterium in the SE group was higher than those in the CON and SB groups (p ≤ 0.05), while the relative abundance of Desulfobacterota, Sutterellaceae, and Erysipelatoclostridium in the SB group was lower than that in the SE group (p ≤ 0.05). Moreover, enzymolysis seaweed powder did not alter the level of intestinal SCFAs in kittens. Conclusively, supplementing kitten diet with enzymolysis seaweed powder can promote intestinal health by enhancing the gut barrier function and optimizing the microbiota composition. Our findings provide new perspectives on the application of enzymolysis seaweed powder.

Effect of Laminaria digitata dietary inclusion and CAZyme supplementation on blood cells, serum metabolites and hepatic lipids and minerals of weaned piglets

Seaweeds, such as Laminaria digitata, are a sustainable alternative to conventional feedstuffs for weaned piglet diets, improving their health and mitigating environmental impacts. L. digitata has a complex cell wall that can be difficult for monogastrics to digest. However, carbohydrate-active enzymes (CAZymes) such as Rovabio® Excel AP and alginate lyase can help break down these polysaccharides and render intracellular nutrients more accessible. This study aimed to evaluate the impact of 10% L. digitata feed inclusion and CAZyme supplementation on piglet blood cells, serum metabolites, liver lipid and mineral profiles. Forty weaned piglets were randomly assigned to one of four diets (n = 10 each): a control diet, 10% L. digitata (LA), 10% L. digitata + 0.005% Rovabio® Excel AP (LAR), and 10% L. digitata + 0.01% alginate lyase (LAL). After two weeks of trial, animals were slaughtered and liver and blood serum samples taken for analysis. The results showed that the LA and LAL diets increased blood lymphocytes, IgG and IgM, and decreased serum lipids, improving both cellular and humoral immune response and cardiovascular health. Dietary CAZymes reversed the anti-inflammatory and hematopoietic effects. Additionally, cortisol levels were reduced with seaweed inclusion compared to the control diet (P < 0.001). In the liver, total n-3 PUFA and n-6/n-3 ratio were increased and decreased, respectively, due to eicosapentaenoic acid and α-linolenic acid accumulation (P < 0.001). However, total liver mineral content was incorporated to a lesser extent with the combined seaweed and enzyme diets (P < 0.001), potentially indicating a negative effect on mineral bioavailability. Overall, results suggest that a 10% L. digitata inclusion can effectively improve piglet health by reducing stress during weaning, without the need for dietary CAZymes.

Maternal microbe-specific modulation of the offspring microbiome and development during pregnancy and lactation

The maternal microbiome is essential for the healthy growth and development of offspring and has long-term effects later in life. Recent advances indicate that the maternal microbiome begins to regulate fetal health and development during pregnancy. Furthermore, the maternal microbiome continues to affect early microbial colonization via birth and breastfeeding. Compelling evidence indicates that the maternal microbiome is involved in the regulation of immune and brain development and affects the risk of related diseases. Modulating offspring development by maternal diet and probiotic intervention during pregnancy and breastfeeding could be a promising therapy in the future. In this review, we summarize and discuss the current understanding of maternal microbiota development, perinatal microbial metabolite transfer, mother-to-infant microbial transmission during/after birth and its association with immune and brain development as well as corresponding diseases.

Nano-selenium and Macleaya cordata Extracts Improved Immune Function and Reduced Oxidative Damage of Sows and IUGR Piglets After Heat Stress of Sows in Late Gestation

To investigate the effects of nano-selenium (nano-Se) and Macleaya cordata extracts (MCE) on immune function and oxidative damage of sows and intrauterine growth retardation (IUGR) piglets exposed to heat stress (HS) in large-scale farms, a 2 × 2 factorial design was adopted in this test, and the two factors were nano-Se (0, 0.50 mg/kg) and MCE (0, 500 mg/kg). A total of 80 sows ([Landrace × Yorkshire] × Duroc, parity 2) were used in a 25-day trial from day 90 of gestation to delivery with 20 replications per group and 1 sow per replication. The dietary treatments of sows were as follows: (1) CON group, basic diet (0.30 mg/kg added Se, sodium selenite); (2) Nano-Se group, basic diet (0.00 mg/kg added Se) + 0.50 mg/kg added nano-Se; (3) MCE group, basic diet (0.00 mg/kg added Se) + 500 mg/kg added MCE; and (4) Combined group, basic diet (0.00 mg/kg added Se) + 0.50 mg/kg added nano-Se and 500 mg/kg added MCE. The activities of serum SOD, CAT, and GSH-Px of sows and IUGR piglets were significantly increased in MCE group and combined group, and the MDA content was extremely decreased. There were extreme differences in serum IgG level of sows and IUGR piglets, colostrum, and serum IgM level of IUGR piglets in MCE group and combined group compared with CON group. Maternal combined diets increased greatly the levels of serum IL-10 and IFN-γ of sows and IUGR piglets, and decreased extremely the contents of serum IL-1β and TNF-α. MCE alone or combination with nano-Se in sow diets decreased greatly mRNA level of Hsp70 and increased mRNA level of Hsp27 in sows and IUGR piglets. In conclusion, nano-Se and/or MCE can be added to sow diets for the amelioration of HS-induced oxidative damage through improving immune function.

An important polysaccharide from fermentum

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Extraction, structure and modification of polysaccharides from fermentum were summarized.

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Structure-activity relationship and application of polysaccharides from fermentum were reviewed.

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It provided a strong basis for the development and application of polysaccharides from fermentum.

Fermentum is a common unicellular fungus with many biological activities attributed to β-polysaccharides. Different in vivo and in vivo experimental studies have long proven that fermentum β-polysaccharides have antioxidant, anti-tumor, and fungal toxin adsorption properties. However, there are many uncertainties regarding the relationship between the structure and biological activity of fermentum β-polysaccharides, and a systematic summary of fermentum β-polysaccharides is still lacking. Herein, we reviewed the research progress about the extraction, structure and modification, structure–activity relationship, activity and application of fermentum β-polysaccharides, compared the extraction methods of fermentum β-polysaccharide, and paid special attention to the structure–activity relationship and application of fermentum β-polysaccharide, which provided a strong basis for the development and application of fermentum β-polysaccharide.

Maternal Dietary Forsythia suspensa Extract Supplementation Induces Changes in Offspring Antioxidant Status, Inflammatory Responses, Intestinal Development, and Microbial Community of Sows

This experiment aims to investigate the effect of maternal diet supplemented with Forsythia suspensa extract (FSE) on the performance, antioxidant status, inflammatory responses, intestinal development, and microbial community of sows. A total of 24 gestating sows (Landrace × Yorkshire) were assigned to 2 treatments with 12 sows per treatment. From d 107 of gestation to d 21 of lactation, sows were supplemented with a basal diet as control (CON) or an FSE diet (basal diet + 100 mg/kg FSE). Compared with CON, sows fed FSE showed lower (P &lt; 0.05) wean-to-estrus interval, body weight loss, and higher (P &lt; 0.05) average daily gain of suckling piglet. Sows fed FSE had reduced (P &lt; 0.05) serum malondialdehyde (MDA) content and enhanced (P &lt; 0.05) catalase and glutathione peroxidase (GSH-Px) contents at farrowing and weaning compared with CON. The suckling piglets of FSE-fed sows had increased (P &lt; 0.05) mRNA expressions of nuclear factor erythroid-2 related factor 2, heme oxygenase-1 in the liver, and lower (P &lt; 0.05) serum MDA content on d 0, 7, and 14 of lactation. Sows fed FSE had lower (P &lt; 0.05) serum tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) contents at farrowing and reduced (P &lt; 0.05) serum IL-6 and IL-8 contents at weaning compared with CON. Piglets from FSE-fed sows had enhanced (P ≤ 0.05) villus height and villus height to crypt depth ratio in the jejunum, and higher (P &lt; 0.05) protein expression of Occludin in jejunal mucosa compared with CON. Sows fed FSE tended to have higher (P = 0.09) relative abundance of Lactobacillus at genus level in feces at weaning compared with CON. Our results showed maternal diet supplemented with FSE in lactating sows could effectively induce improvement of performance, antioxidant status, anti-inflammatory function, intestinal morphology, barrier function, and microbial community.

Maternal and/or direct supplementation with a combination of a casein hydrolysate and yeast β-glucan on post-weaning performance and intestinal health in the pig

A 2 × 2 factorial experiment was conducted to investigate the effect of maternal supplementation from day 83 of gestation and/or direct supplementation from weaning of a bovine casein hydrolysate plus a yeast β-glucan (CH-YBG) on pig performance and intestinal health on day ten post-weaning. Twenty cross bred gilts (Large White × Landrace) were randomly assigned to one of two dietary groups (n = 10 gilts/group): basal diet (basal sows) and basal diet supplemented with CH-YBG (supplemented sows) from day 83 of gestation until weaning (2g/sow/day). At weaning, 120 pigs (6 pigs/sow) were selected. The two dam groups were further divided, resulting in four experimental groups (10 replicates/group; 3 pigs/pen) as follows: 1) BB (basal sows + basal pigs); 2) BS (basal sows + supplemented pigs); 3) SB (supplemented sows + basal pigs); 4) SS (supplemented sows + supplemented pigs). Supplemented pigs were offered 0.5g CH-YBG/kg of feed for 10 days post-weaning. On day 10 post-weaning, 1 pig/pen was humanely sacrificed and samples were taken from the gastrointestinal tract for analysis. Pigs weaned from supplemented sows (SS, SB) had reduced faecal scores and incidence of diarrhoea (P<0.05) compared to pigs weaned from basal sows (BB, BS), with SS pigs not displaying the transient rise in faecal scores seen in the other three groups from day 3 to day 10 post-weaning (P<0.05). Pigs weaned from supplemented sows had reduced feed intake (P<0.05), improved feed efficiency (P<0.05), increased butyrate concentrations (P<0.05), increased abundance of Lactobacillus (P<0.05) and decreased abundance of Enterobacteriaceae and Campylobacteraceae (P<0.05) compared to pigs weaned from basal sows. In conclusion, maternal supplementation increased the abundance of Lactobacillus and decreased the abundance of Enterobacteriaceae and Campylobacteraceae while also increasing butyrate concentrations. The combination of maternal and direct supplementation led to pigs having the lowest faecal scores compared to all other groups.

The Prebiotic Effect of Australian Seaweeds on Commensal Bacteria and Short Chain Fatty Acid Production in a Simulated Gut Model

Diet is known to affect the composition and metabolite production of the human gut microbial community, which in turn is linked with the health and immune status of the host. Whole seaweeds (WH) and their extracts contain prebiotic components such as polysaccharides (PS) and polyphenols (PP). In this study, the Australian seaweeds, Phyllospora comosa, Ecklonia radiata, Ulva ohnoi, and their PS and PP extracts were assessed for potential prebiotic activities using an in vitro gut model that included fresh human faecal inoculum. 16S rRNA sequencing post gut simulation treatment revealed that the abundance of several taxa of commensal bacteria within the phylum Firmicutes linked with short chain fatty acid (SCFA) production, and gut and immune function, including the lactic acid producing order Lactobacillales and the chief butyrate-producing genera Faecalibacteria, Roseburia, Blautia, and Butyricicoccus were significantly enhanced by the inclusion of WH, PS and PP extracts. After 24 h fermentation, the abundance of total Firmicutes ranged from 57.35−81.55% in the WH, PS and PP samples, which was significantly greater (p ≤ 0.01) than the inulin (INU) polysaccharide control (32.50%) and the epigallocatechingallate (EGCG) polyphenol control (67.13%); with the exception of P. comosa PP (57.35%), which was significantly greater than INU only. However, all WH, PS and PP samples also increased the abundance of the phylum Proteobacteria; while the abundance of the phylum Actinobacteria was decreased by WH and PS samples. After 24 h incubation, the total and individual SCFAs present, including butyric, acetic and propionic acids produced by bacteria fermented with E. radiata and U. ohnoi, were significantly greater than the SCFAs identified in the INU and EGCG controls. Most notably, total SCFAs in the E. radiata PS and U. ohnoi WH samples were 227.53 and 208.68 µmol/mL, respectively, compared to only 71.05 µmol/mL in INU and 7.76 µmol/mL in the EGCG samples. This study demonstrates that whole seaweeds and their extracts have potential as functional food ingredients to support normal gut and immune function.

Potential of Oral Nanoparticles Containing Cytokines as Intestinal Mucosal Immunostimulants in Pigs: A Pilot Study

Simple Summary

Antibiotics are essential compounds to cope with bacterial infections. However, their inadequate and excessive use has triggered the rapid arising of antimicrobial-resistant bacteria. In this scenario, immunostimulants, which are molecules that boost the immune system, open up a new approach to face this problem, enhancing treatment efficacy and preventing infections by immune system response. Cytokines are central effector molecules of the immune system, and their recombinant production and administration in animals could be an interesting immune modulation strategy. The aim of this study was the development of a highly stable nanoparticle of porcine cytokines to achieve the immunostimulation of intestinal mucosa in piglets. The outcomes of the present study prove this approach is able to stimulate swine intestinal cells and macrophages in vitro and tends to modulate inflammatory responses in vivo, although further studies are required to definitively evaluate their potential in animals.

Abstract

Antimicrobial resistance is a global threat that is worryingly rising in the livestock sector. Among the proposed strategies, immunostimulant development appears an interesting approach to increase animal resilience at critical production points. The use of nanoparticles based on cytokine aggregates, called inclusion bodies (IBs), has been demonstrated as a new source of immunostimulants in aquaculture. Aiming to go a step further, the objective of this study was to produce cytokine nanoparticles using a food-grade microorganism and to test their applicability to stimulate intestinal mucosa in swine. Four cytokines (IL-1β, IL-6, IL-8, and TNF-α) involved in inflammatory response were produced recombinantly in Lactococcus lactis in the form of protein nanoparticles (IBs). They were able to stimulate inflammatory responses in a porcine enterocyte cell line (IPEC-J2) and alveolar macrophages, maintaining high stability at low pH and high temperature. In addition, an in vivo assay was conducted involving 20 piglets housed individually as a preliminary exploration of the potential effects of IL-1β nanoparticles in piglet intestinal mucosa after a 7 d oral administration. The treated animals tended to have greater levels of TNF-α in the blood, indicating that the tested dose of nanoparticles tended to generate an inflammatory response in the animals. Whether this response is sufficient to increase animal resilience needs further evaluation.

Antioxidant effects of seaweeds and their active compounds on animal health and production - A Review

Natural antioxidants applied as feed additives can improve not only animals’ health and overall performance but also increase their resistance to environmental stress such as heat stress, bad housing conditions, diseases, etc. Marine organisms, for example seaweeds – red, brown, and green macroalgae contain a plethora of biologically active substances, including phenolic compounds, polysaccharides, pigments, vitamins, micro- and macroelements, and proteins known for their antioxidant activity, which can help in the maintenance of appropriate redox status in animals and show pleiotropic effects for enhancing good health, and productivity. The dysregulated production of free radicals is a marked characteristic of several clinical conditions, and antioxidant machinery plays a pivotal role in scavenging the excessive free radicals, thereby preventing and treating infections in animals. Supplementation of seaweeds to animal diet can boost antioxidant activity, immunity, and the gut environment. Dietary supplementation of seaweeds can also enhance meat quality due to the deposition of marine-derived antioxidant components in muscles. The use of natural antioxidants in the meat industry is a practical approach to minimize or prevent lipid oxidation. However, overconsumption of seaweeds, especially brown macroalgae, should be avoided because of their high iodine content. An important point to consider when including seaweeds in animal feed is their variable composition which depends on the species, habitat, location, harvest time, growing conditions such as nutrient concentration in water, light intensity, temperature, etc. This review highlights the beneficial applications of seaweeds and their extracted compounds, which have antioxidant properties as feed additives and impact animal health and production.

Maternal Nutrition During Late Gestation and Lactation: Association With Immunity and the Inflammatory Response in the Offspring

The immature immune system at birth and environmental stress increase the risk of infection in nursing pigs. Severe infection subsequently induces intestinal and respiratory diseases and even cause death of pigs. The nutritional and physiological conditions of sows directly affect the growth, development and disease resistance of the fetus and newborn. Many studies have shown that providing sows with nutrients such as functional oligosaccharides, oils, antioxidants, and trace elements could regulate immunity and the inflammatory response of piglets. Here, we reviewed the positive effects of certain nutrients on milk quality, immunoglobulin inflammatory response, oxidative stress, and intestinal microflora of sows, and further discuss the effects of these nutrients on immunity and the inflammatory response in the offspring.

Feeding Marine Polysaccharides to Alleviate the Negative Effects Associated with Weaning in Pigs

In young pigs, the challenge of weaning frequently leads to dysbiosis. This predisposes pigs to intestinal infection such as post-weaning diarrhoea (PWD). Dietary interventions to reduce PWD have centred on dietary inclusion of antibiotic growth promoters (AGP) and antimicrobials in pig diets, or high concentrations of zinc oxide. These interventions are under scrutiny because of their role in promoting multidrug resistant bacteria and the accumulation of minerals in the environment. There are significant efforts being made to identify natural alternatives. Marine polysaccharides, such as laminarin and fucoidan from macroalgae and chitosan and chito-oligosaccharides from chitin, are an interesting group of marine dietary supplements, due to their prebiotic, antibacterial, anti-oxidant, and immunomodulatory activities. However, natural variability exists in the quantity, structure, and bioactivity of these polysaccharides between different macroalgae species and harvest seasons, while the wide range of available extraction methodologies and conditions results in further variation. This review will discuss the development of the gastrointestinal tract in the pig during the post-weaning period and how feeding marine polysaccharides in both the maternal and the post-weaned pig diet, can be used to alleviate the negative effects associated with weaning.

Effects of dietary Forsythia suspensa extract supplementation to lactating sows and nursery pigs on post-weaning performance, antioxidant capacity, nutrient digestibility, immunoglobulins, and intestinal health

The aim of this study was to determine the effect of dietary Forsythia suspensa extract (FSE) supplementation to lactating sows and nursery pigs on post-weaning performance, antioxidant capacity, immunoglobulins, and intestinal health. Based on backfat, body weight (BW), and parity, 24 gestating sows (Landrace × Yorkshire) with average parity of 3.38 ± 0.61 and BW of 234 ± 6.81 kg were allotted into two dietary treatments (control vs. 100 mg/kg FSE) with 12 sows per treatment from day 107 of gestation to day 21 of lactation. After weaning, based on the initial BW and source litter, 192 nursery pigs (Duroc × [Landrace × Yorkshire], average BW of 6.98 ± 0.32 kg, weaned at day 21) were allotted into four dietary treatments with eight replicate pens per treatment, six pigs per pen for a 4-wk study. The treatments included the following: 1) CC (sows and their piglets both fed control diet); 2) CF (sows fed control diet and their piglets fed FSE diet [containing 100 mg/kg FSE]); 3) FC (sows fed FSE diet and their piglets fed control diet); and 4) FF (sows and their piglets both fed FSE diet). The MIXED procedures of SAS for a split-plot arrangement with sow diet as the whole plot and nursery diet as split plot were used to analyze the data. After weaning, piglets from FSE-fed sows had improved (P < 0.05) average daily gain and feed efficiency, and lower (P < 0.05) diarrhea rate in overall (day 1 to 28) compared with those from sows fed control diet. Piglets from FSE-fed sows also had higher (P < 0.05) contents of immunoglobulin G (IgG), growth hormone, superoxide dismutase (SOD), total antioxidant capacity in serum, villus height in ileum, and villus height to crypt depth ratio in jejunum, as well as lower (P < 0.05) content of malondialdehyde (MDA) in serum and crypt depth in ileum compared with those from sows fed control diet. Piglets fed FSE during nursery had increased (P < 0.05) concentrations of IgG, SOD, and catalase, and decreased (P < 0.05) MDA and tumor nuclear factor-α levels in serum compared with those fed control diet during nursery. Piglets from FC group had increased (P < 0.05) protein expression of occludin in jejunal mucosa and relative abundance of Lactobacillus on genus level in colon compared with those from CC group. In conclusion, for the performance and intestinal health, diets supplemented with FSE during lactation phase seemed more efficient to alleviate weaning stress than the nursery phase. In terms of the antioxidant status and immunoglobulins, FSE supplemented in both phases were efficient for nursery pigs.

Brown Seaweed Food Supplementation: Effects on Allergy and Inflammation and Its Consequences

Multiple health benefits have been ascribed to brown seaweeds that are used traditionally as dietary component mostly in Asia. This systematic review summarizes information on the impact of brown seaweeds or components on inflammation, and inflammation-related pathologies, such as allergies, diabetes mellitus and obesity. We focus on oral supplementation thus intending the use of brown seaweeds as food additives. Despite the great diversity of experimental systems in which distinct species and compounds were tested for their effects on inflammation and immunity, a remarkably homogeneous picture arises. The predominant effects of consumption of brown seaweeds or compounds can be classified into three categories: (1) inhibition of reactive oxygen species, known to be important drivers of inflammation; (2) regulation, i.e., in most cases inhibition of proinflammatory NF-κB signaling; (3) modulation of adaptive immune responses, in particular by interfering with T-helper cell polarization. Over the last decades, several inflammation-related diseases have increased substantially. These include allergies and autoimmune diseases as well as morbidities associated with lifestyle and aging. In this light, further development of brown seaweeds and seaweed compounds as functional foods and nutriceuticals might contribute to combat these challenges.

Seaweed Components as Potential Modulators of the Gut Microbiota

Macroalgae, or seaweeds, are a rich source of components which may exert beneficial effects on the mammalian gut microbiota through the enhancement of bacterial diversity and abundance. An imbalance of gut bacteria has been linked to the development of disorders such as inflammatory bowel disease, immunodeficiency, hypertension, type-2-diabetes, obesity, and cancer. This review outlines current knowledge from in vitro and in vivo studies concerning the potential therapeutic application of seaweed-derived polysaccharides, polyphenols and peptides to modulate the gut microbiota through diet. Polysaccharides such as fucoidan, laminarin, alginate, ulvan and porphyran are unique to seaweeds. Several studies have shown their potential to act as prebiotics and to positively modulate the gut microbiota. Prebiotics enhance bacterial populations and often their production of short chain fatty acids, which are the energy source for gastrointestinal epithelial cells, provide protection against pathogens, influence immunomodulation, and induce apoptosis of colon cancer cells. The oral bioaccessibility and bioavailability of seaweed components is also discussed, including the advantages and limitations of static and dynamic in vitro gastrointestinal models versus ex vivo and in vivo methods. Seaweed bioactives show potential for use in prevention and, in some instances, treatment of human disease. However, it is also necessary to confirm these potential, therapeutic effects in large-scale clinical trials. Where possible, we have cited information concerning these trials.

Prebiotic Effects of Seaweed Polysaccharides in Pigs

To ensure environmental sustainability, according to the European Green Deal and to boost the One Health concept, it is essential to improve animals' health and adopt sustainable and natural feed ingredients. Over the past decade, prebiotics have been used as an alternative approach in order to reduce the use of antimicrobials, by positively affecting the gut microbiota and decreasing the onset of several enteric diseases in pig. However, dietary supplementation with seaweed polysaccharides as prebiotics has gained attention in recent years. Seaweeds or marine macroalgae contain several polysaccharides: laminarin, fucoidan, and alginates are found in brown seaweeds, carrageenan in red seaweeds, and ulvan in green seaweeds. The present review focuses on studies evaluating dietary seaweed polysaccharide supplementation in pig used as prebiotics to positively modulate gut health and microbiota composition.

Seaweed polysaccharide mitigates intestinal barrier dysfunction induced by enterotoxigenic Escherichia coli through NF-κB pathway suppression in porcine intestinal epithelial cells

This study aimed to investigate the protective effects and underlying mechanism of seaweed polysaccharide (SWP) on intestinal epithelial barrier dysfunction induced by E. coli in an IPEC-J2 model. A preliminary study was done to screen optimum SWP concentrations by cell viability, cytotoxicity, apoptosis and proliferation evaluation. The regular study was conducted to evaluate the protective effects of SWP against E. coli challenge via the analysis of transepithelial electrical resistance (TEER), tight junction proteins, NF-κB signalling pathway, proinflammatory cytokines and the E. coli adhesion and invasion. Our results show that 4 h E. coli challenge down-regulated tight junction proteins expression, decreased TEER, activated NF-κB signalling pathway and increased proinflammatory response, which indicates that the E. coli infection model was well-established. Pre-treatment with 240 μg/ml SWP for 24 h alleviated the 4 h E. coli -induced intestinal epithelial barrier dysfunction, as evidenced by the up-regulated expression of Occludin, Claudin-1 and ZO-1 at both mRNA and protein level and the increased TEER of IPEC-J2 cells. Pre-incubation with 240 μg/ml SWP for 24 h inhibited the activation of the NF-κB signalling pathway by 4 h E. coli challenge, including the decreased mRNA expression of TLR-4, MyD88, IκBα, p-65, as well as the reduced ratio of protein expression of p-p65/p65. Also, pre-treatment with 240 μg/ml SWP for 24 h decreased proinflammatory response (IL-6 and TNF-α) induced by 4 h E. coli challenge and decreased the E. coli adhesion and invasion. In conclusion, SWP mitigated intestinal barrier dysfunction caused by E. coli through NF-κB pathway in IPEC-J2 cells and 240 μg/ml SWP exhibited better effect. Our results also provide a fundamental basis for SWP in reducing post-weaning diarrhoea of weaned piglets, especially under E. coli -infected or in-feed antibiotic-free conditions.

Effect of Supplementing Seaweed Extracts to Pigs until d35 Post-Weaning on Performance and Aspects of Intestinal Health

The objective of this study was to examine the effects of feeding laminarin (LAM) and fucoidan (FUC) enriched seaweed extracts up to d35 post-weaning on measures of animal performance, intestinal microbial and transcriptome profiles. 75 pigs were assigned to one of three groups: (1) basal diet; (2) basal diet + 250 ppm fucoidan; (3) basal diet + 300 ppm laminarin with 7 replicates per treatment group. Measures of performance were collected weekly and animals sacrificed on d35 post-weaning for the sampling of gastrointestinal tissue and digesta. Animal performance was similar between the basal group and the groups supplemented with FUC and LAM (P > 0.05). Pigs fed the basal diet had higher alpha diversity compared to both the LAM and FUC supplemented pigs (P < 0.05). Supplementation with LAM and FUC increased the production of butyric acid compared to basal fed pigs (P < 0.05). At genus level pigs fed the LAM supplemented diet had the greatest abundance of Faecalbacterium, Roseburia and the lowest Campylobacter of the three experimental treatments (P< 0.05). While neither extract had beneficial effects on animal performance, LAM supplementation had a positive influence on intestinal health through alterations in the gastrointestinal microbiome and increased butyrate production.

Aquaculture Production of the Brown Seaweeds Laminaria digitata and Macrocystis pyrifera: Applications in Food and Pharmaceuticals

Seaweeds have a long history of use as food, as flavouring agents, and find use in traditional folk medicine. Seaweed products range from food, feed, and dietary supplements to pharmaceuticals, and from bioenergy intermediates to materials. At present, 98% of the seaweed required by the seaweed industry is provided by five genera and only ten species. The two brown kelp seaweeds Laminaria digitata, a native Irish species, and Macrocystis pyrifera, a native New Zealand species, are not included in these eleven species, although they have been used as dietary supplements and as animal and fish feed. The properties associated with the polysaccharides and proteins from these two species have resulted in increased interest in them, enabling their use as functional foods. Improvements and optimisations in aquaculture methods and bioproduct extractions are essential to realise the commercial potential of these seaweeds. Recent advances in optimising these processes are outlined in this review, as well as potential future applications of L. digitata and, to a greater extent, M. pyrifera which, to date, has been predominately only wild-harvested. These include bio-refinery processing to produce ingredients for nutricosmetics, functional foods, cosmeceuticals, and bioplastics. Areas that currently limit the commercial potential of these two species are highlighted.

Effects of Wheat Bran Applied to Maternal Diet on the Intestinal Architecture and Immune Gene Expression in Suckling Piglets

Simple Summary

This research was committed to revealing the potential effects of the use of a high percentage of wheat bran (WB) in the sow’s diets on the offspring’s growth and health, by measuring the bodyweight gain, the morphology of the intestine, as well as the expression levels of immune-related genes in the mucosa of the ileum and colon. Results indicate that adding 25% of wheat bran to the sow’s gestation and 14% to the lactation diet can affect the intestinal architecture and the expression of some inflammation genes, to some extent, in the ileal mucosa in the progeny.

Abstract

The strategy of improving the growth and health of piglets through maternal fiber diet intervention has attracted increasing attention. Therefore, 15 sows were conducted to a wheat bran (WB) group, in which the sows’ diets included 25% of WB in gestation and 14% in lactation, and a control (CON) group, in which the sows’ diets at all stages of reproduction did not contain WB. The results show that maternal high WB intervention seems not to have an impact on the growth of the offspring or the villus height of the duodenum, and the ratio of villi/crypts in the duodenum and jejunum were all higher in piglets born from WB sows, which may indicate that WB piglets had a larger absorption area and capacity for nutrients. The peroxisome proliferator-activated receptor gamma (PPARγ) and interleukin 6 (IL6) expression levels were notably upregulated in the ileal mucosa of WB piglets, while no immune-related genes in the colonic mucosa were affected by the maternal WB supplementation. In conclusion, adding a high proportion of wheat bran to the sow’s gestation and lactation diet can affect the intestinal architecture and the expression of some inflammation genes, to some extent, in the ileal mucosa in the progeny.

Seaweeds in Pig Nutrition

Seaweeds are macroalgae, with different sizes, colors and composition. They consist of brown algae, red algae and green algae, which all have a different chemical composition and bioactive molecule content. The polysaccharides, laminarin and fucoidan are commonly present in brown seaweeds, ulvans are found in green seaweeds and, red algae contain a large amount of carrageenans. These bioactive compounds may have several positive effects on health in livestock. In order to reduce the antimicrobials used in livestock, research has recently focused on finding natural and sustainable molecules that boost animal performance and health. The present study thus summarizes research on the dietary integration of seaweeds in swine. In particular the influence on growth performance, nutrients digestibility, prebiotic, antioxidant, anti-inflammatory, and immunomodulatory activities were considered. The review highlights that brown seaweeds seem to be a promising dietary intervention in pigs in order to boost the immune system, antioxidant status and gut health. Data on the use of green seaweeds as a dietary supplementation seems to be lacking at present and merit further investigation.

Dietary Fiber and Intestinal Health of Monogastric Animals

Animal performance, feed efficiency, and overall health are heavily dependent on gut health. Changes in animal production systems and feed regulations away from the use of antibiotic growth promoters (AGP) have necessitated the identification of strategies to optimize gut health in novel and effective ways. Among alternatives to AGP, the inclusion of dietary fibers (DF) in monogastric diets has been attempted with some success. Alternative feedstuffs and coproducts are typically rich in fiber and can be used in the diets to reduce feed costs and optimize gut health. DF are naturally occurring compounds with a diverse composition and are present in all plant-based feedstuffs. DF stimulate the growth of health-promoting gut bacteria, are fermented in the distal small intestine and large intestine to short-chain fatty acids and have beneficial effects on the immune system. Maternal DF supplementation is one novel strategy suggested to have a beneficial programming effect on the microbial and immune development of their offspring. One mechanism by which DF improves gut health is through maintenance of an anaerobic intestinal environment that subsequently prevents facultative anaerobic pathogens from flourishing. Studies with pigs and poultry have shown that fermentation characteristics and their beneficial effects on gut health vary widely based on type, form, and the physico-chemical properties of the DF. Therefore, it is important to have information on the different types of DF and their role in optimizing gut health. This review will provide information and updates on different types of DF used in monogastric nutrition and its contribution to gut health including microbiology, fermentation characteristics, and innate and adaptive immune responses.

Immunomodulating effect of a seaweed extract from Ulva armoricana in pig: Specific IgG and total IgA in colostrum, milk, and blood

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MSP extract increased IgG anti-Bordetella titers with the highest dosage.

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Improved IgG anti-Bordetella transudation from the blood to the colostrum.

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MSP extract increased total IgA titers in the milk, 7 days after farrowing.

The transfer of passive immunity from sows to piglets can be improved through the administration of immuno-stimulating products before farrowing. This study evaluated the immuno-stimulating effect of an algal sulfated polysaccharide extract (MSP extract) from the green algae Ulva armoricana when administrated orally to sows at the end of gestation. Four diets were tested: Control (no MSP extract), MSP1 (2 g/day of MSP extract), MSP2 (8 g/day), and MSP3 (16 g/day). The experimental diets were provided in two periods: before the last atrophic rhinitis vaccine booster, and a week before farrowing. Anti-Bordetella IgG antibodies were recorded in blood, colostrum, and milk, and total IgA were measured in colostrum and milk. Titer kinetics between the blood sampled before farrowing and colostrum displayed an increase in specific IgG for MSP3. Moreover, the MSP2 diet increased the level of total IgA in milk compared to the control group. Although the immuno-stimulating effect of MSP extract on piglet performance was not concurrent across the different supplementation levels, the present study supports the use of natural algae extract (MSP) as an immunomodulating solution in swine production.

Marine macroalgae as sources of protein and bioactive compounds in feed for monogastric animals

Marine macroalgae are considered as promising sustainable alternatives to conventional terrestrial animal feed resources. The advantages include high growth rate, potential cultivation in saltwater, and no occupation of arable land. Macroalgae are broadly classified as brown (Phaeophyta), red (Rhodophyta) and green (Chlorophyta) algae, and are a diverse group of marine organisms. The nutritional value of macroalgae is highly variable. The protein and essential amino acid content can be low, especially in brown species, and indigestible polysaccharides adversely affect the energy value. Optimal use of macroalgae in feeds requires suitable processing, and biorefinery approaches may increase protein content and improve nutrient availability. Macroalgae are rich in unique bioactive components and there is a growing interest in the potentially beneficial health effects of compounds such as laminarin and fucoidan in different macroalgal and macroalgal products. This review summarizes current literature on different aspects of the use of macroalgae as sources of protein and health-promoting bioactive compounds in feed for monogastric animal species. © 2018 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Effects of inulin supplementation to piglets in the suckling period on growth performance, postileal microbial and immunological traits in the suckling period and three weeks after weaning

The aim of this study was to investigate the effect of inulin (IN) supplementation to suckling piglets at and 3 weeks post-weaning. A total of 72 newborn piglets were used. Twenty-four piglets per group received different amounts of IN during the suckling period: (a) CON: no IN; (b) IN-0.5: 0.5 g IN/d on the 1st week, 1 g IN/d on the 2nd week, 1.5 g IN/d on the 3rd week and 2 g IN/d on the 4th week, or (c) IN-0.75: 0.75 g IN/d on the 1st week, 1.5 g IN/d on the 2nd week, 2.25 g IN/d on the 3rd week and 3 g IN/d on the 4th week. Starting at 28 d of age, piglets were weaned and received a post-weaning diet without inulin during the following 3 weeks. At both 28 d and 49 d of age, piglets were euthanised for sampling. Piglets of group IN-0.5 had the highest body weight starting from the 3rd week (p < 0.05), concomitant with the highest villus height and the ratio of villus height/crypt depth in the jejunum and ileum on both sampling days (p < 0.05). At 28 d of age, an increased concentration of propionate, iso-butyrate or total short chain fatty acids was observed between treatment IN-0.5 and the other groups in the caecum or colon (p < 0.05). Moreover, the relative abundance of Escherichia coli (p = 0.05) and Enterobacteriaceae (p = 0.01) in colonic digesta were reduced in IN-0.5-treated piglets, and in both IN-supplemented groups, colonic interleukin-8, tumor necrosis factor-α and toll-like receptor-4 mRNA abundance were decreased compared to the CON group (p < 0.05). However, at 49 d of age, most of these differences disappeared. In conclusion, treatment IN-0.5 improved during the suckling period of piglets development of intestine, but these beneficial effects were not lasting after weaning, when IN supplementation was terminated. Treatment IN-0.75, however, did not display a prebiotic effect.

Feeding sows resistant starch during gestation and lactation impacts their faecal microbiota and milk composition but shows limited effects on their progeny

Background

Establishment of a beneficial microbiota profile for piglets as early in life as possible is important as it will impact their future health. In the current study, we hypothesized that resistant starch (RS) provided in the maternal diet during gestation and lactation will be fermented in their hindgut, which would favourably modify their milk and/or gut microbiota composition and that it would in turn affect piglets’ microbiota profile and their absorptive and immune abilities.

Methods

In this experiment, 33% of pea starch was used in the diet of gestating and lactating sows and compared to control sows. Their faecal microbiota and milk composition were determined and the colonic microbiota, short-chain fatty acids (SCFA) production and gut health related parameters of the piglets were measured two days before weaning. In addition, their overall performances and post-weaning faecal score were also assessed.

Results

The RS diet modulated the faecal microbiota of the sows during gestation, increasing the Firmicutes:Bacteroidetes ratio and the relative abundance of beneficial genera like Bifidobacterium but these differences disappeared during lactation and maternal diets did not impact the colonic microbiota of their progeny. Milk protein concentration decreased with RS diet and lactose concentration increased within the first weeks of lactation while decreased the week before weaning with the RS diet. No effect of the dietary treatment, on piglets’ bodyweight or diarrhoea frequency post-weaning was observed. Moreover, the intestinal morphology measured as villus height and crypt depths, and the inflammatory cytokines in the intestine of the piglets were not differentially expressed between maternal treatments. Only zonula occludens 1 (ZO-1) was more expressed in the ileum of piglets born from RS sows, suggesting a better closure of the mucosa tight junctions.

Conclusion

Changes in the microbiota transferred from mother to piglets due to the inclusion of RS in the maternal diet are rather limited even though milk composition was affected.

Overview of &#946;-Glucans from Laminaria spp.: Immunomodulation Properties and Applications on Biologic Models

Glucans are a group of glucose polymers that are found in bacteria, algae, fungi, and plants. While their properties are well known, their biochemical and solubility characteristics vary considerably, and glucans obtained from different sources can have different applications. Research has described the bioactivity of β-glucans extracted from the algae of the Laminaria genus, including in vivo and in vitro studies assessing pro- and anti-inflammatory cytokines, vaccine production, inhibition of cell proliferation, and anti- and pro-oxidant activity. Thus, the objective of this article was to review the potential application of β-glucans from Laminaria spp. in terms of their immunomodulatory properties, microorganism host interaction, anti-cancer activity and vaccine development.

Modulation of piglets' microbiota: differential effects by a high wheat bran maternal diet during gestation and lactation

Reaching a beneficial intestinal microbiota early in life is desirable for piglets, as microbiota will impact their future health. One strategy to achieve this is the addition of prebiotics to sows’ diet, as their microbiota will be transferred. Transmission of microbiota to the offspring occurs at birth and during lactation but a transfer might also occur during gestation. The objectives of this study were to determine whether and when (before and/or after birth) a maternal transfer of the microbiota occurs, and to observe the impact of wheat bran (WB) in sows’ diet on their faecal microbiota, their offspring’s microbiota and fermentation profile. Sequencing was performed on DNA extracted from umbilical cord blood, meconium, sows’ faeces and piglets’ colon content. Short-chain fatty acid production was determined in piglets’ distal gut. Different bacteria (mostly Proteobacteria, followed by Firmicutes) were found in the umbilical cord blood, suggesting a maternal transfer occurring already during gestation. Less butyrate was produced in the caecum of WB piglets and a lower concentration of valerate was observed in all intestinal parts of WB piglets. Maternal wheat bran supplementation affected microbiota of sows and piglets differently.

The influence of in ovo injection with the prebiotic DiNovo® on the development of histomorphological parameters of the duodenum, body mass and productivity in large-scale poultry production conditions

Background

Among various feed additives currently used in poultry nutrition, an important role is played by bioactive substances, including prebiotics. The beneficial effect of these bioactive substances on the gastrointestinal tract and immune system give rise to improvements in broiler health and performance nutrition, thus increasing the productivity of these birds. An innovative method for introducing bioactive substances into chickens is the in ovo injection into eggs intended for hatching. The aim of the study was to evaluate the development of histomorphological parameters of the duodenum and productivity in chickens injected in ovo with the prebiotic DiNovo® (extract of Laminaria species of seaweed, BioAtlantis Ltd., Ireland) on d 12 of incubation, under large - scale, high density poultry production conditions.

Results

There was no significant impact of the injection of DiNovo® prebiotic on the production parameters of broiler chickens (body weight, FCR, EBI and mortality) obtained on d 42 of rearing. No significant impact of the DiNovo® injection on the duodenum weight and length was observed, as well as on the CSA, diameter and muscular layer thickness of the duodenum. The in ovo injection of DiNovo® significantly increased the width of the duodenal villi (P < 0.05) and crypt depth (P < 0.01) of chickens on d 21 of rearing. Other histomorphological parameters of duodenal villi at d 42 of chickens rearing such as: the height, width, and cross section area of villi were significantly greater in chickens from the control group compared to those from the DiNovo® group (P < 0.05 and P < 0.01).

Conclusions

In conclusion, this study demonstrates that injection of DiNovo® prebiotic into the air chamber of egg significantly influences the histomorphological parameters on d 21 of rearing without negatively affecting productivity in chickens at the end of rearing.

Plant Immunity Inducer Development and Application

Plant immunity inducers represent a new and rapidly developing field in plant-protection research. In this paper, we discuss recent research on plant immunity inducers and their development and applications in China. Plant immunity inducers include plant immunity-inducing proteins, chitosan oligosaccharides, and microbial inducers. These compounds and microorganisms can trigger defense responses and confer disease resistance in plants. We also describe the mechanisms of plant immunity inducers and how they promote plant health. Furthermore, we summarize the current situation in plant immunity inducer development in China and the global marketplace. Finally, we also deeply analyze the development trends and application prospects of plant immunity inducers in environmental protection and food safety.

Novel marine polysaccharides and maternal nutrition to stimulate gut health and performance in post-weaned pigs

Post-weaning complications in piglets are characterised by a reduction in feed intake and growth, atrophy of small-intestine architecture, upregulation of intestinal inflammatory cytokines, alterations in gastrointestinal microflora, diarrhoea and heightened susceptibility to infection. Traditional measures to reduce weaning-associated intestinal dysfunction have centred on dietary inclusion of antibiotic growth promoters in weaning pig diets, or high concentrations of dietary minerals in the form of zinc oxide. However, these strategies are under scrutiny because of their role in promoting multi-drug resistant bacteria and the accumulation of minerals in the environment. Up to recently, the main focus on finding alternatives to in-feed antibiotic growth promoters has been on dietary manipulations post-weaning, through the use of feed additives in the post-weaning diet. However, there are also other strategies that could enhance the growth and health of the newly weaned pig. One of these strategies is the use of maternal nutrition to improve growth and health in her offspring. The development of the immune system begins in utero and is further developed after the colonisation of the gastrointestinal tract with microbiota during birth and post-natal life. The early establishment of this relationship is fundamental to the development and long-term maintenance of gut homeostasis. There are significant efforts being made to identify natural alternatives to support the development of the piglet gastrointestinal tract, in particular during the weaning period. Chemodiversity in nature, including microorganisms, terrestrial plants, seaweeds and marine organisms, offers a valuable source of novel bioactives. This review will discuss the development of the intestinal tract in the pig during gestation, lactation and post-weaning periods and the factors that influence intestinal health post-weaning. It will also discuss how feeding marine bioactives in both the maternal diet and the piglet diet can be used to alleviate the negative effects associated with weaning.

Comparison of Saccharina japonica-Undaria pinnatifida Mixture and Minoxidil on Hair Growth Promoting Effect in Mice

BACKGROUND

Algae have traditionally been used for promotion of hair growth. Use of hair regrowth drugs, such as minoxidil, is limited due to side effects. The aim of this study was to examine a mixture of Saccharina japonica and Undaria pinnatifida (L-U mixture) on hair growth and to compare the promoting effect of hair growth by a 3% minoxidil and a L-U mixture.

METHODS

To evaluate the hair growth-promoting activity, saline, 50% ethanol, 3% minoxidil, and the L-U mixture were applied 2 times a day for a total of 14 days on the dorsal skin of C57BL/6 mice after depilation. Analysis was determined by using a high-resolution hair analysis system, real-time polymerase chain reaction, and H&E staining.

RESULTS

On day 14, the hair growth effect of the L-U mixture was the same as that of the 3% minoxidil treatment. The L-U mixture significantly (P<0.05) stimulated hair growth-promoting genes, as vascular endothelial growth factor (VEGF) and insulin-like growth factor -1. Increase of VEGF was observed in the L-U mixture group compared with minoxidil and the negative control. In contrast, the L-U mixture suppressed the expression of transforming growth factor-β1, which is the hair loss-related gene. In histological examination in the L-U mixture and minoxidil groups, the induction of an anagen stage of hair follicles was faster than that of control groups.

CONCLUSIONS

This study provides evidence that the L-U mixture can promote hair growth in mice, similar to the effect from minoxidil, and suggests that there is potential application for hair loss treatments.

Marine macroalgal extracts to maintain gut homeostasis in the weaning piglet

The mammalian gastrointestinal tract (GIT) is a dynamic environment, where a symbiotic relationship exists between the resident microbiota and the digestive and immune systems of the host. The development of the immune system begins in-utero and is further developed after the colonization of the GIT with microbiota during birth and postnatal life. The early establishment of this relationship is fundamental to the development and long-term maintenance of gut homeostasis. Regulatory mechanisms ensure an appropriate level of immune reactivity in the gut to accommodate the presence of beneficial and dietary microorganisms, whereas allowing effective immune responses to clear pathogens. However, unfavorable alterations in the composition of the microbiota, known as dysbiosis, have been implicated in many conditions including post-weaning diarrhea in pigs. Weaning is a major critical period in pig husbandry. It involves complex dietary, social, and environmental stresses that interfere with gut development. Post-weaning complications in piglets are characterized by a reduction in-feed intake and growth, atrophy of small intestine architecture, upregulation of intestinal inflammatory cytokines, alterations in GIT microflora, diarrhea, and heightened susceptibility to infection. These challenges have been controlled with in-feed prophylactic antibiotics and dietary minerals. However, these strategies are under scrutiny because of their role in promoting multidrug resistant bacteria and the accumulation of minerals in the environment, respectively. Therefore, significant efforts are being made to identify natural alternatives to support homeostasis in the piglet GIT, in particular during the weaning period. Chemodiversity in nature; including microorganisms, terrestrial plants, seaweeds, and marine organisms, offers a valuable source for novel bioactives. In this review, we discuss the advances in our understanding of the immune mechanisms by which the dynamic interplay of the intestinal microbiota and its host normally favors a homeostatic, symbiotic relationship, and how feeding macroalgal bioactives in both the maternal diet and the piglet diet, can be used to support this symbiotic relationship in times of challenge.

Fucoidan Extracted from Hijiki Protects Brain Microvessel Endothelial Cells Against Diesel Exhaust Particle Exposure-Induced Disruption

This study was performed to evaluate the protective effects of fucoidan against the decreased function of primary cultured bovine brain microvessel endothelial cells (BBMECs) after exposure to diesel exhaust particles (DEPs). BBMECs were extracted from bovine brains and cultured until confluent. To evaluate the function of BBMECs, we performed a permeability test using cell-by-cell equipment and by Western blot analysis for zonular occludens-1 (ZO-1), which is a tight junction protein of BMECs, and evaluated oxidative stress in BBMECs using the DCFH-DA assay and the CUPRAC-BCS assay. The increased oxidative stress in BBMECs following DEP exposure was suppressed by fucoidan. In addition, permeability of BBMECs induced by DEP exposure was decreased by fucoidan treatment. Our results showed that fucoidan protects against BBMEC disruption induced by DEP exposure. This study provides evidence that fucoidan might protect the central nervous system (CNS) against DEP exposure.

Maternal supplementation of seaweed-derived polysaccharides improves intestinal health and immune status of suckling piglets

The experiment investigated the effect of maternal dietary supplementation of seaweed-derived polysaccharides (SDP) (-SDP v. +SDP, n   20) from day 83 of gestation until weaning (day 28) on selected sow faeces and piglet digesta microbiota populations, piglet small-intestinal morphology, and intestinal nutrient transporter and inflammatory cytokine gene expression at birth, 48 h after birth and weaning. The effect of maternal dietary treatment on the piglet gene expression profile of inflammatory cytokines in the colon following a lipopolysaccharide (LPS) challenge was also investigated. Dietary SDP reduced sow faecal Enterobacteriaceae gene numbers at parturition. Small-intestinal morphology, nutrient transporter and cytokine gene expression in newborn piglets did not differ between maternal dietary treatments (P > 0·10). At 48 h after birth, sodium-glucose-linked transporter 1 gene expression was down-regulated in the ileum of piglets suckling the SDP-supplemented sows compared with those suckling the basal sows (P = 0·050). There was a SDP × LPS challenge interaction on IL-1 and IL-6 gene expression in the colon of piglets (P < 0·05). The gene expression of IL-1 and IL-6 was down-regulated in the LPS-challenged colon of piglets suckling the SDP sows compared with those suckling the basal sows (P < 0·05). However, there was no difference in IL-1 and IL-6 gene expression in the unchallenged colon between treatment groups. At weaning, piglets suckling the SDP-supplemented sows had increased villus height in the jejunum and ileum compared with those suckling the basal-fed sows (P < 0·05). In conclusion, maternal dietary SDP supplementation enhanced the immune response of suckling piglets and improved gut morphology, making them more immune competent to deal with post-weaning adversities.

Influence of dietary supplementation with flaxseed and lactobacilli on the cells of local innate immunity response in the jejunal mucosa in piglets after weaning

A histological study was designed to determine the influence of flaxseed and/or lactobacilli inclusion in the diet of piglets from 10 days before to 21 days after weaning. The selected inflammatory cell population incidence in the piglet jejunal mucosa was investigated. Significantly higher numbers of myeloperoxidase-positive (P<0.01) and CD163-positive (P<0.001) cells in the jejunal mucosa were recorded on the weaning day and for 7 days after (P<0.001 and P<0.01, respectively) in the flaxseed group compared with the basal diet. The number of intraepithelial lymphocytes was also significantly increased until 3 days after weaning (P<0.001). A prolonged significant increase in the myeloperoxidase-positive cells and intraepithelial lymphocyte numbers in the flaxseed+lactobacilli group was detected. In contrast, the number of CD163-positive cells in the flaxseed+lactobacilli group was significantly lower on the day of weaning (P<0.05) and 3 days after (P<0.01). The same effect was observed in the group with lactobacilli alone during the first 3 days after weaning (P<0.05 and P<0.01, respectively) and these findings indicate down-regulation of CD163 expression in the jejunal mucosa by lactobacilli. The presence of lactobacilli in the diet had a stimulatory effect on goblet cell quantity in the epithelium (P<0.001) and a distinct 50% reduction in the flaxseed group (P<0.01) compared with the basal diet was observed on the weaning day. A significant increase in myeloperoxidase-positive cell number in the jejunal mucosa in the flaxseed+lactobacilli group was the only significant difference (P<0.05 and P<0.01, respectively) found 21 days after weaning in comparison with all the other groups, indicating the pro-inflammatory effect of this feed additive combination. We conclude that dietary supplementation with flaxseed and lactobacilli on the cells of local innate immunity response in the jejunal mucosa in piglets after weaning might be linked with significant anti-inflammatory effects in the jejunal mucosa.

Effect of maternal supplementation with seaweed extracts on growth performance and aspects of gastrointestinal health of newly weaned piglets after challenge with enterotoxigenic Escherichia coli K88

In the present study, a 2 × 2 factorial arrangement was conducted to investigate the effect of maternal supplementation with seaweed extracts ( - SWE v. +SWE, n 20) from day 83 of gestation until weaning (day 28) on post-weaning (PW) growth performance, faecal score, faecal enterotoxigenic Escherichia coli (ETEC) toxin quantification, intestinal histology and cytokine mRNA of unchallenged and ETEC-challenged pigs. Pigs were ETEC challenged on day 9 PW. There was a maternal treatment × challenge (SWE × ETEC) interaction effect on growth performance and faecal score (P< 0.05). Pigs from SWE-supplemented sows and ETEC-challenged (SE) had higher average daily gain (ADG) during 0-13 d PW and reduced faecal score during 0-72 h post-challenge than those from basal-fed sows and ETEC-challenged (BE) (P< 0.05). However, there was no difference between unchallenged pigs from the SWE-supplemented sows (SC) and basal-fed sows (BC) (P>0.10). Pigs from the SWE-supplemented sows had reduced heat-labile enterotoxin gene copy numbers than those from the basal-fed sows (P< 0.05). Maternal SWE supplementation increased the villus height in the ileum of pigs (P< 0.05). There was a SWE × ETEC interaction effect (P< 0.05) on IL-6 mRNA and a SWE × gastrointestinal (GI) region interaction effect (P< 0.05) on transforming growth factor-β1 (TGF-β1) and TNF-α mRNA. IL-6 mRNA was down-regulated in SC pigs than BC pigs (P< 0.05). However, there was no difference in IL-6 mRNA between SE and BE pigs. The mRNA of TGF-β1 and TNF-α was down-regulated in the colon of pigs from the SWE-supplemented sows compared with those from the basal-fed sows (P< 0.05). However, there was no difference in TGF-β1 and TNF-α mRNA in the ileum between the pigs from the SWE-supplemented sows and basal-fed sows. In conclusion, maternal SWE supplementation improves ADG and the aspects of GI health of weaned pigs following an ETEC challenge.

Maturation of mouse bone marrow dendritic cells (BMDCs) induced by Laminaria japonica polysaccharides (LJP)

The seaweed Laminaria japonica has been investigated in a laboratory research for its medical significance and LJP has been purified now. The objective of present study was to look at effect of LJP on structural, phenotypic and functional maturation of murine BMDCs. The structural maturation of BMDCs induced by LJP was evaluated by transmission electron microscopy (TEM); The phenotypic maturation of BMDCs was studied by flow cytometry(FCM) and functional maturation of BMDCs was analyzed by FITC-dextran, acid phosphatase (ACP) activity and enzyme linked immunosorbent assay (ELISA). We hereby proved that LJP markedly induced maturation of BMDCs with the data of decreased the number of lysosomes, upregulated expression of CD80, CD83, CD86, CD40 and MHC II key membrane molecules on BMDCs, downregulated phagocytosis, enriched production of IL-12 and TNF-α secreted by BMDCs. Therefore it should be concluded that LJP was with strong ability to induce maturation of BMDCs. Our data provided direct evidence to suggest that LJP could be considered as an immune stimulant in improving immune handicapped situation and as a useful adjuvant in vaccine designing.