Anti-coccidial efficacy of Enteromorpha prolifera polysaccharide in indigenous chickens of Northwest Ethiopia.

BACKGROUND: A variety of bioactive compounds isolated from various botanical sources have been found to have therapeutic and immunotherapeutic effects on chicken coccidiosis. AIM: This study aimed to evaluate the anti-coccidial potential of Enteromorpha prolifera polysaccharide (EP) in indigenous chickens in Northwest Ethiopia. MATERIALS AND METHODS: A total of 78 male indigenous chickens were used for this study. The study had two treatment groups: (1) the EP non-supplemented group (those fed on diets without EP and Eimeria oocyst inoculated) and (2) the EP group (those receiving diets supplemented with 400 mg EP/kg diet and Eimeria oocyst inoculated). Each treatment group had five replications. Following fourteen days of EP supplementation, 1.5 × 104 oocysts of mixed Eimeria species were inoculated into individual birds. RESULTS: EP-supplemented chicken showed significantly lower (p < 0.05) oocyst counts compared to non-supplemented ones on 9 and 11 days post-challenge. In addition, chickens in the EP-supplemented group showed less severe lesion scores, with an average score of 1.33. Chickens that received EP showed a maximum of 27.27% protection against lesions. In contrast, the non-supplemented chickens had a lower percentage of protection (19.83%). The maximum anti-coccidial index value (146.98) was obtained from EP-supplemented chickens. Chickens in the EP-supplemented group exhibited a significantly higher (p < 0.05) weight gain. CONCLUSION: Overall, the inclusion of EP in chickens' diets shows promise as a potential anti-coccidial strategy. However, additional research is required to explore the mechanisms by which EP in chickens' diet could involve in increasing the protection ability of chickens against coccidiosis.

Effect of ecotype and Enteromorpha polysaccharide supplementation on the growth performance of indigenous chickens in Northwest Ethiopia.

The study was conducted to compare the growth performance of indigenous chickens and evaluate the effect of Enteromorpha prolifera (EP) supplementation on the growth of chickens. A total of 180 indigenous chicken ecotypes (Sinan, Dembecha, North Achefer, and Jawi) were used in the study. Chicken ecotype and sex had a highly significant (p < 0.001) effect on body weight and average daily gain (ADG). The highest final body weight (1811.5 ± 16.6 g) and ADG at twenty weeks of age (12.76 ± 0.12 g) were recorded for the Jawi ecotype, followed by the North Achefer. A significantly higher body weight and ADG in male chickens than female chickens were observed. The EP supplemented (EP +) chickens showed a significantly (P < 0.05) higher body weight and ADG than the non-supplemented (EP-) chickens. The interaction effect of ecotype and feed type was not statistically significant on body weight in the starter and grower phases, except at week 9. In the first four weeks, the highest (100%) and lowest (91.7%) survivability rates were recorded for the Sinan ecotype and the Jawi ecotype, respectively. In general, the Jawi and North Achefer ecotypes had better growth performance, and the Sinan ecotype relatively showed better survivability. EP supplementation could improve the growth performance of chickens.

Effects of genotype and Phytolacca dodecandra (Endod) supplementation on growth performance, carcass traits, blood profiles, and breast meat quality of chickens.

In this study, we investigated the effects of genotype and Phytolacca dodecandra (Endod) supplementation on the growth, carcass traits, blood profiles, and breast meat quality of chickens. The study lasted for 18 weeks and involved 360 unsexed day-old chicks divided into nine groups with 40 chicks each, replicated four times with 10 chicks per replication. The genotypes studied were Naked-neck * Tetra H, Normal-feathered * Tetra H, crosses and Tetra H * Tetra H, while the diets included a standard commercial ration (C), Phytolacca dodecandra (Endod) at 1 g/kg (C+1), and Phytolacca dodecandra (Endod) at 2 g/kg (C+2). Results showed that both diet and genotype influenced growth performance indicators like final body weight, body weight change, average daily gain, and feed conversion ratio, particularly during the grower and entire phases. When compared to the control diet, the Phytolacca dodecandra (Endod) chicks supplemented at 1 g/kg showed better performances. The genotypes also affected dressing percentage, breast, thigh, keel bone, and gizzard components, with higher values found in the Naked-neck by Tetra H cross. The supplemented chicken group exhibited an improvement in the dressing percentage and breast muscle in comparison to the control. Blood parameters were also significantly influenced (P < 0.01) by genotype, diet, and their interaction. Supplementation significantly (P < 0.01) increased protein levels while reducing the cholesterol and triglyceride levels in the blood. Incorporating Phytolacca dodecandra (Endod) at a rate of 1 g/kg into the diet of chickens brought a significant improvement in the protein content, and a reduction in the fat content, of their breast muscles. In general, the study indicates that adding up to 2 g/kg of Phytolacca dodecandra (endod) to chicken feed enhances growth performance traits, carcass traits, blood profiles, and breast muscle protein levels, without any negative consequences.

Stepwise co-fermented traditional Chinese medicine byproducts improve antioxidant and anti-inflammatory effects in a piglet model.

BACKGROUND: Lianhua Qingwen capsule is a traditional Chinese medicine (TCM) formula having antiviral and anti-inflammatory activities. During capsule production, a large amount of byproducts will be yielded and disposed of as waste by burying. Resourceful utilization of these kinds of TCM byproducts as feed additives through stage-based co-fermentation using enzyme and probiotics could reduce environmental stress and resource shortage. The in vitro characterization and the supplementary effects of fermented TCM byproducts (FTCM) for weaned piglets (initial body weight: 7.23 ± 0.33 kg; dose: basal diet + 300 mg kg-1 FTCM) were investigated. RESULTS: Higher reducing sugar content, total flavonoid content, flavonoid compounds (e.g. tectoridin, tricetin, flavone, apigenin, naringenin) and total antioxidant activity were determined in the FTCM compared to spontaneously fermented and unfermented materials. Supplementation of the FTCM to piglets did not significantly affect the feed intake, body weight gain and feed/gain ratio, but significantly decreased a proinflammatory cytokine, IL-8, and increased intestinal total antioxidant activity (TAC) and superoxide dismutase (SOD) activity. Moreover, FTCM supplementation increased α-diversity of the colonic microbiota accompanied with increased abundance of Prevotella genus and Treponema berlinense species. Correlation analysis indicates that T. berlinense is responsible for the decreased IL-8 level and enhanced intestinal TAC and SOD activities which might be mediated by a homoserine lactone molecule (3-oxo-C14). CONCLUSION: Overall, the stepwise co-fermentation enriched bioactive compounds within the TCM byproducts and their dietary supplementation did not generate any side effect on growth performance but displayed beneficial effects on enrichment of potential probiotic T. berlinense and relevant functions. © 2023 Society of Chemical Industry.

Advances on novel iron saccharide-iron (III) complexes as nutritional supplements.

Iron deficiency is prevalent worldwide, and iron supplementation is a promising strategy to address iron needs of the body. However, traditional oral supplements such as ferrous sulfate, ferrous succinate, and ferrous gluconate are absorbed in the form of ferrous ions, leading to lipid peroxidation and side effects due to other reasons. In recent years, saccharide-iron (III) complexes (SICs) as novel iron supplements have aroused attention for the high iron absorption rate and no gastrointestinal irritation at oral doses. In addition, research on the biological activities of SICs revealed that they also exhibited good abilities in treating anemia, eliminating free radicals, and regulating the immune response. This review focused on the preparation, structural characterization, and bioactivities of these new iron supplements, as promising candidates for the prevention and treatment of iron deficiency.

Structural characteristics and immunomodulatory effects of sulfated polysaccharides derived from marine algae.

Marine algae are becoming an important source of valuable candidates of functional food that remain unexplored. Compositional analysis showed that marine algae contain essential nutrients, such as carbohydrates, proteins, fats, and minerals, of which polysaccharides are the main bioactive component. Depending on the source, marine algae polysaccharides are sulfated, which have diverse structures and compositions that influence their biological activities. A growing body of evidence has demonstrated that sulfated polysaccharides derived from marine algae (SPs) exhibit various bioactivities, especially immunomodulation. This review aims at summarizing the structural characteristics of SPs, their immunomodulatory effects, and the structural-immunomodulatory activity relationships between them from articles in recent decade, in order to provide a theoretical basis for the further applications of SPs as promising food or feed additives and possible health products to modulate the immune response.

Impact of dietary supplementation with N-carbamoyl-aspartic acid on serum metabolites and intestinal microflora of sows.

BACKGROUND: N-Carbamoyl-aspartic acid (NCA) is a critical precursor for de novo biosynthesis of pyrimidine nucleotides. To investigate the cumulative effects of maternal supplementation with NCA on the productive performance, serum metabolites and intestinal microbiota of sows, 40 pregnant sows (∼day 80) were assigned into two groups: (1) the control (CON) and (2) treatment (NCA, 50 g t-1 NCA). RESULTS: Results showed that piglets from the NCA group had heavier birth weight than those in the CON group (P < 0.05). In addition, maternal supplementation with NCA decreased the backfat loss of sows during lactation (P < 0.05). Furthermore,16S-rRNA sequencing results revealed that maternal NCA supplementation decreased the abundance of Cellulosilyticum, Fournierella, Anaerovibrio, and Oribacterium genera of sows during late pregnancy (P < 0.05). Similarly, on the 14th day of lactation, maternal supplementation with NCA reduced the diversity of fecal microbes of sows as evidenced by significantly lower observed species, Chao1, and Ace indexes, and decreased the abundance of Lachnospire, Faecalibacterium, and Anaerovorax genera, while enriched the abundance of Catenisphaera (P < 0.05). Untargeted metabolomics showed that a total of 48 differentially abundant biomarkers were identified, which were mainly involved in metabolic pathways of arginine/proline metabolism, phenylalanine/tyrosine metabolism, and fatty acid biosynthesis, etc. CONCLUSION: Overall, the results indicated that NCA supplementation regulated intestinal microbial composition of sows and serum differential metabolites related to arginine, proline, phenylalanine, tyrosine, and fatty acids metabolism that may contribute to regulating the backfat loss of sows, and the birth weight and diarrhea rate of piglets. © 2022 Society of Chemical Industry.

Maternal catalase supplementation regulates fatty acid metabolism and antioxidant ability of lactating sows and their offspring.

Introduction and methods: As a crucial antioxidant enzyme, catalase (CAT) could destroy the cellular hydrogen peroxide to mitigate oxidative stress. The current study aimed to investigate the effects of maternal CAT supplementation from late gestation to day 14 of lactation on antioxidant ability and fatty acids metabolism with regard to the sow-piglet-axis. On day 95 of gestation, forty sows were divided into control (CON) group (fed a basal diet) and CAT group (fed a basal diet supplemented with 660 mg/kg CAT), the feeding experiment ended on day 14 of lactation. Results: The lactating sows in the CAT group produced more milk, and had higher antioxidant enzymes activity including POD and GSH-Px (P < 0.05), lower content of serum LDL as well as plasmic C18:3n3 content (P < 0.05). Additionally, maternal CAT supplementation improved offspring's body weight at day 14 of nursing period and ADG (P < 0.05), and regulated the antioxidant ability as evidenced by decreased related enzymes activity such as T-AOC and CAT and changed genes expression level. It significantly affected lipid metabolism of suckling piglets manifested by increasing the serum ALT, CHOL, and LDL (P < 0.05) level and modulating plasma medium- and long-chain fatty acids (MCFAs and LCFAs), as well as regulating the genes expression involved in lipid metabolism. Conclusion: Maternal CAT supplementation could regulate the fatty acid composition and enhance the antioxidant ability of sows and offspring during the lactating period and further promote the growth of suckling piglets. These findings might provide a reference value for the utilization of CAT as supplement for mother from late pregnancy to lactation period to promote the fatty acid metabolism of offspring.

New trends in immunocastration and its potential to improve animal welfare: a mini review.

Castration is frequently used to reduce aggressive behavior and improve the meat quality of animals. Traditionally, surgical and mechanical castration are used to sterilize the animals, but these approaches are associated with a high level of pain, stress, long recovery periods, and post-operative infections. Immunocastration is a new animal-friendly, painless alternative castration technique that is used to prevent undesired sexual behavior, reduce aggressive behavior, prevent unwanted pregnancy, control wildlife populations and wandering species, enhance growth performance, improve meat quality, and treat various sex hormone-dependent disorders. The mechanism of immunocastration includes the immunological block of the hypothalamic-pituitary-gonadal axis (HPG axis) which inhibits gonadotropin secretions, causes atrophy of gonadal tissues, and inhibits gametogenesis, resulting in infertility in both female and male mammals. By the mid-1990s, various immunocastration vaccines have been tested in different animal models to achieve successful castration effects. Recently, genetic immunocastration especially DNA vaccine has gained increasing attention due to its safety, being animal-friendly, and being easy to use. This review aims to evaluate the potential of traditional castration methods, as well as the current status of immunocastration vaccines, their effects, and future prospective.

Microbiome-metabolome analysis reveals alterations in the composition and metabolism of caecal microbiota and metabolites with dietary Enteromorpha polysaccharide and Yeast glycoprotein in chickens.

The intestinal microbiome is responsible for the fermentation of complex carbohydrates and orchestrates the immune system through gut microbiota-derived metabolites. In our previous study, we reported that supplementation of Enteromorpha polysaccharide (EP) and yeast glycoprotein (YG) in combination synergistically improved antioxidant activities, serum lipid profile, and fatty acid metabolism in chicken. However, the mechanism of action of these polysaccharides remains elusive. The present study used an integrated 16S-rRNA sequencing technology and untargeted metabolomics technique to reveal the mechanism of action of EP+YG supplementation in broiler chickens fed basal diet or diets supplemented with EP+YG (200mg/kg EP + 200mg/kg YG). The results showed that EP+YG supplementation altered the overall structure of caecal microbiota as evidenced by ß diversities analysis. Besides, EP+YG supplementation changed the microbiota composition by altering the community profile at the phylum and genus levels. Furthermore, Spearman correlation analysis indicated a significant correlation between altered microbiota genera vs serum cytokine levels and microbiota genera vs volatile fatty acids production. Predicted functional analysis showed that EP+YG supplementation significantly enriched amino acid metabolism, nucleotide metabolism, glycan biosynthesis and metabolism, energy metabolism, and carbohydrate metabolism. Metabolomics analysis confirmed that EP+YG supplementation modulates a myriad of caecal metabolites by increasing some metabolites, including pyruvic acid, pyridoxine, spermidine, spermine, and dopamine, and decreasing metabolites related to lipid metabolisms such as malonic acid, oleic acid, and docosahexaenoic acid. The quantitative enrichment analysis results further showed that glycolysis/gluconeogenesis, citric acid cycle, tyrosine metabolism, glycine, serine, and threonine metabolism, and cysteine and methionine metabolism were the most important enriched pathways identified with enrichment ratio >11, whereas, fatty acid biosynthesis and biosynthesis of unsaturated fatty acids pathways were suppressed. Together, the 16S-rRNA and untargeted metabolomics results uncovered that EP+YG supplementation modulates intestinal microbiota and their metabolites, thereby influencing the important metabolism pathways, suggesting a potential feed additive.

Maternal pyrimidine nucleoside supplementation regulates fatty acid, amino acid and glucose metabolism of neonatal piglets.

Pyrimidine nucleosides (PN) are abundant in mammalian milk and mainly involved in glycogen deposition and lipid metabolism. To investigate the effects of maternal supplementation with pyrimidine nucleoside on glucose, fatty acids (FAs), and amino acids (AAs) metabolism in neonatal piglets. Forty pregnant sows were randomly assigned into the control (CON) group (fed a basal diet, n = 20) or the PN group (fed a basal diet supplemented with PN at 150 g/t, n = 20). Litter size, born alive and birth litter weight were recorded. The serum and placenta of sows, and jejunum and liver of neonatal piglets were sampled. The results indicated that supplementing sow diets with PN decreased birth mortality and increased the birth weight of piglets (P < 0.05). In addition, neonates from sows supplemented with PN had higher glucose levels in serum and liver compared with the CON group (P < 0.05). Moreover, maternal PN supplementation regulated the ratio of saturated FAs and polyunsaturated FAs, and AAs content in serum and liver of piglets (P < 0.05). Furthermore, an up-regulation of mRNA expression of genes related to glucose and AA transport were observed in the neonatal jejunum from the PN group (P < 0.05). Additionally, hepatic protein expressions of phosphorylated hormone-sensitive lipase (P-HSL), HSL, sterol regulatory element-binding transcription factor 1c (SREBP-1c), and phosphorylated protein kinase B (P-AKT) was higher in the piglets from the PN group than the CON group (P < 0.05). Together, maternal PN supplementation may regulate nutrient metabolism of neonatal piglets by modulating the gene expression of glucose and AA transporters in placenta and jejunum, and the gene and protein expression of key enzymes related to lipid metabolism in liver of neonatal piglets, which may improve the reproductive performance of sows.

Enteromorpha polysaccharide and yeast glycoprotein mixture improves growth, antioxidant activity, serum lipid profile and regulates lipid metabolism in broiler chickens.

This study aimed to analyze the growth performance, antioxidant activity, serum lipid profile, meat quality, and lipid metabolism of broiler chickens fed mixtures containing Enteromorpha polysaccharide (EP) and yeast glycoprotein (YG). A total of 400 one-day-old broiler chickens were randomly divided into 4 treatment groups of 10 replicates with 10 birds each replicate. The dietary treatments consisted of the control group (fed basal diet), and diets supplemented with Enteromorpha polysaccharide (EP; 400 mg/kg), yeast glycoprotein (YG;400 mg/kg), and EP+YG (200 mg/kg EP + 200 mg/kg YG). Compared with the control group, EP+YG supplementation enhanced growth performance and significantly reduced (P < 0.05) serum total triglyceride (TG), cholesterol (CHOL), and low-density lipoprotein LDL levels, and increased high-density lipoprotein (HDL) levels. Besides, birds fed EP+YG supplemented diet exhibited higher (P < 0.05) serum catalase (CAT), total antioxidant capacity, superoxide dismutase (SOD), and lower malonaldehyde (MDA) activities, and upregulated expressions of related genes, such as nuclear factor-erythroid factor 2-related factor 2 (NRF2), SOD1, and glutathione peroxidase 4 (GPX4) in the liver and intestinal tissues than the control group. Interestingly, higher (P < 0.05) serum SOD and lower MDA contents were observed in the EP+YG group than in either EP or YG group, suggesting a synergetic effect. Breast meat from EP+YG supplemented group had significantly higher redness value (a*), and lower pH24, total saturated fatty acid profiles, C14:0, C16:0, C18:0 fatty acid, atherogenic index, and thrombogenicity index than meat from the control group (P < 0.05). Furthermore, the mRNA expressions of fatty acid synthesis genes were downregulated (P < 0.05), whereas lipid ß-oxidation-related genes were upregulated (P < 0.05) in the liver of the EP+YG supplemented group than in the control group. Overall, our data suggest that dietary EP+YG inclusion may have a synergistic effect, and therefore improve growth performance, regulate serum biochemical indexes, enhance antioxidant activity, and modulate lipid metabolism in broilers, indicating that it is a potential feed additive for chickens.

Potential Feed Additives as Antibiotic Alternatives in Broiler Production.

This article aimed to describe the current use scenario, alternative feed additives, modes of action and ameliorative effects in broiler production. Alternative feed additives have promising importance in broiler production due to the ban on the use of certain antibiotics. The most used antibiotic alternatives in broiler production are phytogenics, organic acids, prebiotics, probiotics, enzymes, and their derivatives. Antibiotic alternatives have been reported to increase feed intake, stimulate digestion, improve feed efficiency, increase growth performance, and reduce the incidence of diseases by modulating the intestinal microbiota and immune system, inhibiting pathogens, and improving intestinal integrity. Simply, the gut microbiota is the target to raise the health benefits and growth-promoting effects of feed additives on broilers. Therefore, naturally available feed additives are promising antibiotic alternatives for broilers. Then, summarizing the category, mode of action, and ameliorative effects of potential antibiotic alternatives on broiler production may provide more informed decisions for broiler nutritionists, researchers, feed manufacturers, and producers.

Curcumin and Intestinal Oxidative Stress of Pigs With Intrauterine Growth Retardation: A Review.

Intrauterine growth restriction (IUGR) refers to the slow growth and development of a mammalian embryo/fetus or fetal organs during pregnancy, which is popular in swine production and causes considerable economic losses. Nutritional strategies have been reported to improve the health status and growth performance of IUGR piglets, among which dietary curcumin supplementation is an efficient alternative. Curcumin is a natural lipophilic polyphenol derived from the rhizome of Curcuma longa with many biological activities. It has been demonstrated that curcumin promotes intestinal development and alleviates intestinal oxidative damage. However, due to its low bioavailability caused by poor solubility, chemical instability, and rapid degradation, the application of curcumin in animal production is rare. In this manuscript, the structural-activity relationship to enhance the bioavailability, and the nutritional effects of curcumin on intestinal health from the aspect of protecting piglets from IUGR associated intestinal oxidative damage were summarized to provide new insight into the application of curcumin in animal production.

Effect of Maternal Catalase Supplementation on Reproductive Performance, Antioxidant Activity and Mineral Transport in Sows and Piglets.

This experiment was conducted to investigate the effects of maternal catalase (CAT) supplementation on reproductive performance, antioxidant enzyme activities, mineral transport, and mRNA expression of related genes in sows and offspring. A total of 40 pregnant sows at 95 days of gestation with similar parity (3−5 parities) and back-fat thickness were assigned randomly and equally into the control (CON) group (fed a basal diet) and CAT group (fed a basal diet supplemented with 660 mg/kg CAT; CAT activity, 280 U/g). The reproductive performance was recorded, and the placenta and blood samples of sows and neonatal piglets, as well as the jejunum and ileum samples from neonatal boars (eight replicates per group), were collected. Results showed that dietary supplementation with CAT significantly decreased the intrauterine growth restriction (IUGR) rate and increased the activity of serum CAT in neonatal piglets and umbilical cords (p < 0.05). In addition, CAT supplementation tended to improve total antioxidant capacity (T-AOC) levels in the maternal serum (p = 0.089) and umbilical cords of piglets (p = 0.051). The serum calcium (Ca), manganese (Mn), and zinc (Zn) of farrowing sows and Mn concentration in the umbilical cord, and serum Ca, magnesium (Mg), copper (Cu), and Mn of neonatal piglets were significantly increased (p < 0.05) in the CAT group. CAT supplementation downregulated mRNA expression of TRPV6 and CTR1 (p < 0.05), Cu/Zn SOD (p = 0.086) in the placenta and tended to increase the mRNA expression of the glutathione peroxidase 1 (GPX1) (p = 0.084), glutathione peroxidase 4 (GPX4) (p = 0.063), and CAT (p = 0.052) genes in the ileum of piglets. These results showed that the maternal CAT supplementation improved fetal growth by decreasing the IUGR rate, and modulated antioxidant activity, as well as mineral elements in the pregnant sows and their piglets.

Immunocastration with gene vaccine (KISS1) induces a cell-mediated immune response in ram testis: A transcriptome evaluation.

Immunocastration vaccines achieve their effects through neutralization of the endogenous hormone by the humoral antibody produced against the immunized genes, but there is little information regarding cell-mediated immune response on the gonadal function of the immunized model is available. In this study, we used ram as a model animal to identify the cellular immune response in testicular tissues of rams immunized with intranasal KISS1 gene vaccine. The immune castration model was evaluated by sexual behaviours, spermatogenesis and serum hormone profiles after the KISS1 gene immunization. Transcriptome analysis of testicular tissues was carried out to identify the expressions of protein-coding genes involved in cellular immunity. The results showed that we successfully constructed the KISS1 immune castration ram model, in which testicular growth and development, testosterone and kisspeptin-54 levels, and sexual function were suppressed in immunized rams (p < .05). Using Hiseq™ 2000 high sequencing for ram testicular, we identified 21 differentially expressed genes (DEGs) related to cellular immunity, of which, 14 genes were upregulated and seven genes were downregulated in the testis of the immunized group (p < .05). The Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment showed that these differentially expressed genes were enriched in the antigen presentation process mediated by MHC class I and the cytotoxic pathway mediated by natural killer cells. It is concluded that KISS1 gene vaccine induced the cell-mediated immune response in testicular tissue to suppress reproductive activities in rams.

Dietary Enteromorpha polysaccharide-Zn supplementation regulates amino acid and fatty acid metabolism by improving the antioxidant activity in chicken.

BACKGROUND: Enteromorpha prolifera (E. prolifera) polysaccharide has become a promising feed additive with a variety of physiological activities, such as anti-oxidant, anti-cancer, anti-diabetic, immunomodulatory, hypolipidemic, and cation chelating ability. However, whether Enteromorpha polysaccharide-trace element complex supplementation regulates amino acid and fatty acid metabolism in chicken is largely unknown. This study was conducted to investigate the effects of E. prolifera polysaccharide (EP)-Zn supplementation on growth performance, amino acid, and fatty acid metabolism in chicken. METHODS: A total of 184 one-day-old Ross-308 broiler chickens were randomly divided into two treatment groups with 8 replicates, 12 chickens per replicate, and fed either the basal diet (control group) or basal diet plus E. prolifera polysaccharide-Zinc (400 mg EP-Zn/kg diet). RESULTS: Dietary EP-Zn supplementation significantly increased (P < 0.05) the body weight, average daily gain, muscle antioxidant activity, serum HDL level, and reduced serum TG and LDL concentration. In addition, dietary EP-Zn supplementation could modulate ileal amino acid digestibility and upregulate the mRNA expression of amino acid transporter genes in the jejunum, ileum, breast muscle, and liver tissues (P < 0.05). Compared with the control group, breast meat from chickens fed EP-Zn had higher (P < 0.05) Pro and Asp content, and lower (P < 0.05) Val, Phe, Gly, and Cys free amino acid content. Furthermore, EP-Zn supplementation upregulated (P < 0.05) the mRNA expressions of mTOR and anti-oxidant related genes, while down-regulated protein degradation related genes in the breast muscle. Breast meat from EP-Zn supplemented group had significantly lower (P < 0.05) proportions of Σn-3 PUFA, and a higher percentage of Σn-6 PUFA and the ratio of n-6/n-3 PUFA. Besides, EP-Zn supplementation regulated lipid metabolism by inhibiting the gene expression of key enzymes involved in the fatty acid synthesis and activating genes that participated in fatty acid oxidation in the liver tissue. CONCLUSIONS: It is concluded that EP-Zn complex supplementation regulates apparent ileal amino acid digestibility, enhances amino acid metabolism, and decreases oxidative stress-associated protein breakdown, thereby improving the growth performance. Furthermore, it promotes fatty acid oxidation and restrains fat synthesis through modulating lipid metabolism-related gene expression.

Enteromorpha prolifera polysaccharide-zinc complex modulates the immune response and alleviates LPS-induced intestinal inflammation via inhibiting the TLR4/NF-κB signaling pathway.

Enteromorpha prolifera polysaccharide-zinc (EP-Zn), a kind of polysaccharide-zinc complex, has been shown to improve the immune response and reduce the inflammatory factors in weaned piglets. Yet, the molecular mechanism remains unclear. The present study was conducted to investigate the immunomodulating activity and anti-inflammatory mechanism of EP-Zn in mice. Different doses (350 mg kg-1, 700 mg kg-1, 1050 mg kg-1 and 1400 mg kg-1) of EP-Zn were administered to C57BL/6J mice for 28 days. The results showed that under physiological conditions, 350 mg kg-1 EP-Zn stimulated cytokine (TNF-α, IL-1ß, IL-6 and IL-10) secrection, regulated the intestinal microbiota, and reduced the levels of short-chain fatty acids (SCFAs) (acetic acid and propionic acid). In addition, in the LPS-induced inflammation model, EP-Zn pretreatment effectively alleviated LPS-induced shortening of colonic length and increased MPO and DAO contents, improved intestinal physical barrier function by modulating mucosal structure, and attenuated intestinal inflammation via inhibiting the TLR4/NF-κB signaling pathway. These findings suggested that EP-Zn exerted immunomodulatory and anti-inflammatory activities under physiological and inflammatory conditions, respectively.

Dietary Enteromorpha Polysaccharide Enhances Intestinal Immune Response, Integrity, and Caecal Microbial Activity of Broiler Chickens.

Marine algae polysaccharides have been shown to regulate various biological activities, such as immune modulation, antioxidant, antidiabetic, and hypolipidemic. However, litter is known about the interaction of these polysaccharides with the gut microbiota. This study aimed to evaluate the effects of marine algae Enteromorpha (Ulva) prolifera polysaccharide (EP) supplementation on growth performance, immune response, and caecal microbiota of broiler chickens. A total of 200 1-day-old Ross-308 broiler chickens were randomly divided into two treatment groups with ten replications of ten chickens in each replication. The dietary treatments consisted of the control group (fed basal diet), and EP group (received diet supplemented with 400 mg EP/kg diet). Results showed that chickens fed EP exhibited significantly higher (P < 0.05) body weight and average daily gain than the chicken-fed basal diet. In addition, significantly longer villus height, shorter crypt depth, and higher villus height to crypt depth ratio were observed in the jejunal and ileal tissues of chickens fed EP. EP supplementation upregulated the mRNA expression of NF-κB, TLR4, MyD88, IL-2, IFN-α, and IL-1ß in the ileal and jejunal tissues (P < 0.05). Besides, we observed significantly higher (P < 0.05) short-chain volatile fatty acids (SCFAs) levels in the caecal contents of the EP group than in the control group. Furthermore, 16S-rRNA analysis revealed that EP supplementation altered gut microbiota and caused an abundance shift at the phylum and genus level in broiler chicken. Interestingly, we observed an association between microbiota and SCFAs production. Overall, this study demonstrated that supplementation of diet with EP promotes growth performance, improves intestinal immune response and integrity, and modulates the caecal microbiota of broiler chickens. This study highlighted the application of marine algae polysaccharides as an antibiotic alternative for chickens. Furthermore, it provides insight to develop marine algae polysaccharide-based functional food and therapeutic agent.

Dietary Amylose/Amylopectin Ratio Modulates Cecal Microbiota and Metabolites in Weaned Goats.

Increasing the ratio of amylose in the diet can increase the quantity of starch that flows to the large intestine for microbial fermentation. This leads to the alteration of microbiota and metabolite of the hindgut, where the underlying mechanism is not clearly understood. The present study used a combination of 16S amplicon sequencing technology and metabolomics technique to reveal the effects of increasing ratios of amylose/amylopectin on cecal mucosa- and digesta-associated microbiota and their metabolites in young goats. Twenty-seven Xiangdong black female goats with average body weights (9.00 ± 1.12 kg) were used in this study. The goats were randomly allocated to one of the three diets containing starch with 0% amylose corn (T1), 50% high amylose corn (T2), and 100% high amylose corn (T3) for 35 days. Results showed that cecal valerate concentration was higher (P < 0.05) in the T2 group than those in the T1 and T3 groups. The levels of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 were decreased (P < 0.05) in cecal tissue while IL-10 was increased (P < 0.05) in the T2 group when compared with T1 or T3 groups. At the phylum level, the proportion of mucosa-associated Spirochaetes was increased (P < 0.05), while Proteobacteria was deceased by feeding high amylose ratios (P < 0.05). The abundance of Verrucomicrobia was decreased (P < 0.05) in the T3 group compared with the T1 and T2 groups. The abundance of digesta-associated Firmicutes was increased (P < 0.05) while Verrucomicrobia and Tenericutes were deceased (P < 0.05) with the increment of amylose/amylopectin ratios. The LEfSe analysis showed that a diet with 50% high amylose enriched the abundance of beneficial bacteria such as Faecalibacterium and Lactobacillus in the digesta and Akkermansia in the mucosa compared with the T1 diet. The metabolomics results revealed that feeding a diet containing 50% high amylose decreased the concentration of fatty acyls-related metabolites, including dodecanedioic acid, heptadecanoic acid, and stearidonic acid ethyl ester compared with the T1 diet. The results suggested that a diet consisting of 50% high amylose could maintain a better cecal microbiota composition and host immune function.