Improving gut functions and egg nutrition with stevia residue in laying hens.

This study aimed to investigate the effect of stevia residue (STER) on the production performance, egg quality and nutrition, antioxidant ability, immune responses, gut morphology and microbiota of laying hens during the peak laying period. A total of 270 Yikoujingfen NO. 8 laying hens (35 wk of age) were randomly divided into 5 treatments. The control group fed a basal diet and groups supplemented with 2, 4, 6, and 8% STER. The results showed that STER significantly increased egg production, the content of amino acids (alanine, proline, valine, ornithine, asparagine, aspartic acid, and cysteine) in egg whites, and decreased the yolk color (P < 0.05). Additionally, STER significantly increased acetate, HOMOγ linolenic acid and cis-13, 16-docosadienoic acid levels in egg yolk (P < 0.05). IL-2, IL-4, and IL-10 levels in serum significantly increased by STER (P < 0.05), while IL-1ß significantly decreased (P < 0.05). STER also increased total antioxidant activity (T-AOC) in the liver and estradiol level in the oviduct (P < 0.05), but decreased the cortisol level in the oviduct (P < 0.05). For the intestinal morphology, the jejunal villus height and crypt-to-villus (V:C) significantly increased by STER (P < 0.05). STER increased the relative abundance of Actinobacteriota (P < 0.05), while deceased Proteobacteria, Desulfobacterota, and Synergistota (P < 0.05). In conclusion, STER improved egg production, quality and nutrition, improved the immune responses, antioxidant capabilities, estrogen level, gut morphology, and increased the relative abundance of beneficial bacteria while decreased the harmful bacteria. Among all treatments, 4 and 6% STER supplementation yielded the most favorable results in terms of enhancing production performance, egg nutrition, gut health, and immune capabilities in laying hens.

Effects of a combination of lauric acid monoglyceride and cinnamaldehyde on growth performance, gut morphology, and gut microbiota of yellow-feathered broilers.

A total of 480 one-day-old male yellow-feathered broilers were randomly divided into 4 groups with 6 replicates of 20 chicks per replicate. A basal diet was administered to the control group (CON), whereas CML350, CML500, and CML1000 groups were fed with basal diet supplemented with 350, 500, and 1,000 mg/kg of lauric acid monoglyceride and cinnamaldehyde complex, respectively. However, adding 500 mg/kg of lauric acid monoglyceride and cinnamaldehyde complex improved weight gain (P < 0.01), enhanced intestinal morphology, increased serum total protein and albumin content, and total antioxidant capacity (P < 0.01), and significantly increased the Chao1 and Ace indices (P < 0.01), indicating an increase in the richness of the gut microbiota. At the phylum level, CML500 group reduced the abundance of Fusobacteriota at 21 d and Proteobacteria at 42 d (P < 0.01). At the genus level, CML500 group increased the abundance of Faecalibacterium and Alistipes at 42 d (P < 0.01) and decreased the abundance of Escherichia-Shigella (P < 0.01). At the species level, CML500 group reduced the abundance of Escherichia coli at 42 d (P < 0.01) and increased the abundance of Alistipes_sp_CHKCI003 at 42 d (P < 0.01). According to these results, adding 500 mg/kg of lauric acid monoglyceride and cinnamaldehyde complex in feed can improve the growth performance, intestinal morphology, and gut microbiota of yellow-feathered broilers.

Review: A systematic review of the effects of functional amino acids on small intestine barrier function and immunity in piglets.

The need to reduce the use of antibiotics and zinc oxide at the pharmacological level, while preserving the performance of postweaning piglets, involves finding adequate nutritional strategies which, coupled with other preventive strategies, act to improve the sustainability of the piglet-rearing system. Amino acids (AAs) are the building blocks of proteins; however, they also have many other functions within the body. AA supplementation, above the suggested nutritional requirement for piglets, has been investigated in the diets of postweaning piglets to limit the detrimental consequences occurring during this stressful period. A systematic review was carried out to summarise the effects of AAs on gut barrier function and immunity, two of the parameters contributing to gut health. An initial manual literature search was completed using an organised search strategy on PubMed, utilising the search term " AND ". These searches yielded 302 articles (published before October 2021); 59 were selected. Based on the method for extracting data (synthesis of evidence), this review showed that L-Arginine, L-Glutamine and L-Glutamate are important functional AAs playing major roles in gut morphology and immune functions. Additional benefits of AA supplementation, refereed to a supplementation above the suggested nutritional requirement for piglets, could also be observed; however, data are needed to provide consistent evidence. Taken together, this review showed that supplementation with AAs during the weaning phase supported a plethora of the physiological functions of piglets. In addition, the data reported confirmed that each amino acid targets different parameters related to gut health, suggesting the existence of potential synergies among them.

Effect of Monovalent Copper Oxide and Potentiated Zinc Oxide on Growth Performance and Gut Morphology of Broiler Chickens Challenged with Coccidiosis.

An experiment was conducted to evaluate the effect of copper oxide (Cu2O) and potentiated zinc oxide (ZnO) on performance, intestinal morphology, oocyst excretion, coccidial lesion scores, and antioxidant properties in broilers during an Eimeria spp. challenge. A total of 288 1-day-old male broiler chickens (Ross 308) were divided into 18 treatments. Treatments included three levels of Cu (0, 15, or 150 mg/kg) from Cu2O and three levels of Zn (0, 80, or 160 mg/kg) from potentiated ZnO which were added to the basal diet and fed to broilers with or without challenge, using a completely randomized design in a factorial arrangement for 42 days. Live body weight, feed intake, mortality, and the cause of death were recorded weekly and histomorphology of jejunum was measured at the end of the experiment. Results showed that birds fed Cu and Zn linearly decreased (P < 0.0001) oocyst shedding. The number of excreted oocysts was reduced eight times in broilers fed a diet containing 150 mg/kg copper from Cu2O and 160 mg/kg zinc from potentiated ZnO, compared to the infected group without Cu and Zn supplementation (P < 0.0001). Microscopic features of both non-challenged and challenged broiler jejunum revealed significant improvement along with increased Cu2O and potentiated ZnO doses. Supplementation of Cu2O and potentiated ZnO decreased the jejunum structure damages and intestinal lesion score (P < 0.002). Eimeria caused a decrease (P < 0.006) in total antioxidant capacity. Superoxide dismutase increased by dietary zinc supplementation (P < 0.05). Results suggested that a combination of Cu2O and potentiated ZnO could exhibit efficient anticoccidial activity.

Effects of two host-associated probiotics Bacillus mojavensis B191 and Bacillus subtilis MRS11 on growth performance, intestinal morphology, expression of immune-related genes and disease resistance of Nile tilapia (Oreochromis niloticus) against Streptococcusiniae.

The intensification and diversification of production systems have increased the incidence of diseases, which are usually treated with antibiotics. However, its use should be restricted due to the increasing prevalence of antibiotic-resistant bacteria. Probiotics represent therefore an alternative environmentally friendly strategy for improving growth and disease resistance in aquaculture. Considering that host-derived probiotics may offer greater advantages than those from other environments in terms of safety and efficacy, two potential host-associated probiotic strains (Bacillus mojavensis B191 and Bacillus subtilis MRS11) were used in the present study, which were previously isolated from intestinal mucus of Nile tilapia (Oreochromis niloticus). This study was conducted to assess the effects of dietary administration of two Bacillus strains on growth performance, intestinal morphology, immunity, and disease resistance of Nile tilapia. A total of 375 fish were randomly divided into five groups in triplicate. Nile tilapia were fed a basal diet (control group) or a basal diet supplemented with Bacillus mojavensis B191 (BM) or Bacillus subtilis MRS11 (BS) spores at different concentrations of 1 × 106 (BM6 and BS6, respectively) and 1 × 108 (BM8 and BS8, respectively) CFU/g of feed for 60 days. Moreover, the survival rate of tilapia upon challenge with Streptococcus iniae was determined following the feeding trial. After the feeding trial, the growth performances were significantly improved in all probiotic-fed groups, with the BS8 group being the highest. Light and electron microscopy observations revealed elevated goblet cells, intestinal villus length (except BM8), microvilli length, microvilli density, and perimeter ratio increase in the intestine of all probiotic-fed groups compared with the control group. Regarding the expression analysis, HSP70 gene was only up-regulated in the BM8 group and a general trend of up-regulation of some immune-related cytokines (TGF-ß, IL-10, TNF-α and IL-1ß) was observed in all probiotic-fed groups. Likewise, the best protection against Streptococcus iniae was observed in the BS8 group, followed by BS6, BM6 and BM8 groups. Altogether, dietary probiotic supplementation with BS8 and BM6 may improve growth performance, intestinal morphology, immunity, and disease resistance in Nile tilapia.

Suitability of dried olive pulp in slow-growing broilers: performance, meat quality, oxidation products, and intestinal mucosa features.

To assess the effect of dietary dried olive pulp (DOP) on growth performance, meat traits and oxidation, and intestinal mucosa features, a total of 180 male slow-growing broiler chickens (Hubbard) were divided into 3 groups and fed 3 isonitrogenous and isoenergetic diets from 14 d of age until slaughter (49 d). The treatments varied according to 3 DOP levels: a control diet without DOP (DOP0, 0%) and 2 test diets containing 5 and 10% of DOP (DOP5 and DOP10, respectively). Duodenal morphometric indices were measured at the end of the feeding period and included: villus height, crypt depth, villus-to-crypt ratio, and villus surface area. Dietary DOP had no adverse effect on growth performance, dressing percentage, or breast yield of broilers. The breast muscle pH at 24 h was significantly higher in birds fed DOP10 diet compared to those on DOP0 and DOP5 diets. Meat color was also affected by dietary treatments. Feeding DOP did not influence breast meat fatty acid composition, whereas meat from DOP-fed broilers resulted less susceptible to lipid and protein oxidation compared to control diet. Including DOP up to 10% in diet resulted in higher duodenal villus height, crypt depth, and villus height to crypt depth ratio as well as villus surface area. Based on our findings, dietary DOP supported productive traits of slow-growing broilers preserving meat from oxidation and improving intestinal morphometric features. As a result, the current study assessed that olive by-product can be used in broiler ration, resulting in a valuable ingredient as replacement for conventional feeds, which could reduce feeding costs due to the low cost of the olive by-product. Thus, using olive by-products as poultry feed may become economically feasible for producers where the olive oil industries play an important economic role.

Effects of an emulsifier blend supplementation on growth performance, nutrient digestibility, intestinal morphology, and muscle fatty acid profile of broiler chickens fed with different levels of energy and protein.

The effects of emulsifier blend (EB) supplementation of diets with various levels of metabolizable energy (ME) and crude protein (CP) on broiler performance, digestibility, gut morphology, and muscle fatty acid profile were investigated over a 42-d period. Diets were arranged factorially (2 × 2 × 3) and consisted of 2 levels of ME (normal [commercially recommended levels] and low [100 kcal/kg reduction in dietary ME]), 2 levels of CP and limiting amino acids (normal [commercially recommended levels] and low [95% of the normal CP level]), and 3 levels of EB supplementation (0, 1, and 2 g/kg of diet). A total of 1,200 one-day-old male broiler chickens (Ross 308) were randomly assigned to 12 treatment groups (5 pens/treatment with 20 birds/pen). Supplemental EB linearly improved (P < 0.05) final body weight, overall average daily gain, and feed conversion ratio, but the magnitude of the responses was greater in low-ME and low-CP treatments, resulting in significant ME × CP × EB interactions. Similarly, the inclusion of EB in the diet, particularly at 2 g/kg, increased the ileal digestibility of crude protein and crude fat, as well as the AMEn value (P < 0.05), but the response was greater at lower ME concentration, indicating significant ME × EB interactions. Additionally, there were CP × EB interactions (P < 0.05) for duodenal villus height and villus height/crypt depth ratio, indicating that the effect of EB on these responses was more marked at lower dietary CP levels. An increase in dietary EB levels was accompanied by a linear increase in the concentration of total saturated fatty acids and a linear decrease (P < 0.05) in the concentrations of total polyunsaturated fatty acids in both breast and thigh meat. In conclusion, the positive effects of EB supplementation, particularly at a dietary inclusion level of 2 g/kg, were clearly evident in broiler chickens fed with low nutrient diets (-100 Kcal/kg ME and/or -5% CP and limiting amino acids) in terms of growth performance, nutrient digestibility, and gut morphology.

Lipid Compositions of Total Parenteral Nutrition Affect Gut Peyer's Patches and Morphology in Mice.

INTRODUCTION: Although parenteral nutrition (PN) is the only option for providing adequate nutrition to patients who cannot tolerate oral ingestion, it severely impairs intestinal barrier function in terms of morphology and immunity. While addition of either soybean oil (SO) or fish oil (FO) to PN partially reverses these defects, the effects of the oil composition (FO/SO ratio) on morphology and gut-associated lymphoid tissues (GALT) have yet to be elucidated. We focused on the effects of the FO/SO ratio in PN on the number of lymphocytes in Peyer's patches, immunoglobulin A levels, and intestinal structures. METHODS: Male ICR mice (n = 61) were randomized into five groups; oral nutrition (Chow, n = 14) and four groups receiving PN without oral nutrition. PN solutions contained fat emulsions with the following FO:SO ratios: 0:1 (SO, n = 12), 1:11.5 (11.5FSO, n = 17),1:2 (1:2FSO, n = 13) and 1:0 (FO, n = 5). All mice underwent jugular vein catheter insertion. The PN groups were given isocaloric and isonitrogenous nutritional support with 20% of total calories from fat emulsions with equivalent fat delivery in 11.9 g/kg/d. After 5 d of each feeding, Peyer's patches lymphocytes were isolated from the small intestine, counted and analyzed with flowcytometry for determination of their phenotypes (αßTCR+, γδTCR+, CD4+, CD8+ and B cells). Villus height and crypt depth of the jejunum and ileum were evaluated with hematoxylin-eosin staining. Immunoglobulin A levels in the intestinal washings were also determined. RESULTS: Numbers of total lymphocytes and B lymphocytes in PP were increased in the 1:2 FSO-PN but neither in the 1:11.5 FSO nor the FO group, as compared to the SO group. There were no marked differences among the groups in numbers neither of total T cells nor in any of T cell phenotypes determined. The 1:2 FSO group showed significantly greater villus height and crypt depth than the SO group. IgA levels did not differ significantly among the four PN groups. CONCLUSIONS: The PN with 1:2 FSO (FO:SO = 1:2) maintained lymphocyte numbers in PP and intestinal villus morphology at levels nearly the same as those obtained with chow feeding. An appropriate ratio of FO to SO in PN is expected to prevent immunological impairment and morphological atrophy of the gut associated with lack of oral nutrition.

Sophorolipid protects against early-weaning syndrome by improving the gut microenvironment in early-weaned piglets.

BACKGROUND: In animals, weaning stress is the first and most critical stress. Weaning can negatively affect the growth performance of animals physically, psychologically, and pathologically. Our previous studies on the HT-29 cell line and early-weaned rats demonstrated that adequate sophorolipid (SPL) supplementation in feed could enhance the mucin-producing and wound healing capacities of the gut defense system by modulating gut microbiota. METHODS: We conducted an experiment with one hundred forty 21-day-old early weaned piglets (L x Y x D). They were allocated into 4 treatment and 7 replications (4 pigs per pen) according to their initial body weight. Body weight and feed intake were measured biweekly during experimental period. After 6 weeks, 28 pigs were randomly selected and sacrificed to collect plasma, jejunum, and cecal content samples. RESULTS: Dietary SPL supplementation at 5 and 10 mg/kg quadratically increased the average daily gain during the experimental period in the treatment groups when compared with the control group. The albumin levels of piglets fed with the SPL supplemented diet were downregulated to the normal range. Moreover, in feed, SPL supplementation at 5 and 10 mg/kg improved jejunal histological indices and gene expression levels related to mucin secretion and local inflammation markers. Consistent with these results, adequate SPL supplementation (5 and 10 mg/kg) increased the population of Prevotella, a beneficial bacterium, and its short-chain fatty acid production in the ceca of piglets. CONCLUSIONS: The occurrence of diarrhea after weaning in piglets could be reduced by feeding a 10 ppm of SPL supplemented diet which improves the gut defense system by improving the microbial population and enhancing mucin layer integrity.

Longitudinal investigations of anatomical and morphological development of the gastrointestinal tract in goats from colostrum to postweaning.

The digestive tract development in goat kids around weaning is vital to the establishment of digestion and absorption function, growth, and health of adults. The objective was to explore the effects of age and solid feed on the anatomical and morphological development of the gastrointestinal tract of Laiwu Black goat kids. Forty-eight female Laiwu Black goats at 8 ages (1, 7, 14, 28, 42, 56, 70, and 84 d; 6 goats per group) were selected and killed for anatomical and morphological analysis. The goats experienced the following 4 diet phases: maternal colostrum (MC; d 1, d 7), maternal milk (MM; d 14, d 28), maternal milk plus solid diet (MMSD; d 42, d 56) and only solid diet (OSD; d 70, d 84). The body and carcass weights were not significantly changed during MC and MM phases but changed during the MMSD phase. The absolute growth of body and carcass weights were higher in the MMSD phase than in MM phase. In addition, the dressing percentage was the highest in the MMSD phase. The body size indices evolved progressively and increased over time. The percentage of internal and external organs to body weight decreased over time, whereas the percentage to complex stomach percentage increased. The rumen and omasum weight experienced synchronous absolute growth over time, especially in the OSD phase. In contrast, the absolute growth of the reticulum and abomasum was the highest in MMSD and MC phases, respectively. After weaning, the goats showed the highest papillae height, lamina propria, muscle layer thickness, and epithelial thickness. The OSD phase showed the highest colonic mucosa thickness, ileal villus height, and ileal muscle layer thickness. The crypt depth was higher in the MMSD phase than in the MM phase. Moreover, the crypt depth and muscle layer thickness of jejunum increased over time. Furthermore, duodenal crypt depth, muscle layer thickness, and epithelial thickness increased in the OSD phase compared with other stages. In conclusion, the histological investigation supports the improvement of the morphological development of the digestive tract and the growth performance in the solid feed phase. It is recommended to add solid food as early as 4 wk old.

Supplementation of Mixed Organic Acids Improves Growth Performance, Meat Quality, Gut Morphology and Volatile Fatty Acids of Broiler Chicken.

Background: Organic acid as a green feed additive is increasingly favoured by enterprises and scholars, but little emphasis has been placed on the effect of organic acids on broiler meat quality. Methods: A total of 192 male chicks (one-day-old, weighted 48.40 ± 0.64 g) were selected to investigate the effect of mixed organic acids (MOA) on growth performance, meat quality as well as fatty acids profile. Chicks were randomly allocated to three treatments with eight replicates and eight chicks per replicate, including a corn-soybean basal diet with 0 (CON), 3000 mg/kg (low MOA; LMOA), and 6000 mg/kg (high MOA; HMOA) MOA. The experiment was divided into starter (d 1-d 21) and grower (d 22-d 42) phases. Results: Broilers supplemented with LMOA and HMOA enhanced (p < 0.05) the final body weight and average daily gain in the grower and overall phases. An improved (p < 0.05) feed conversion ratio in the grower and overall phases was observed in broilers supplemented with LMOA. The breast and thigh muscles pH24h were higher (p < 0.05) in broilers fed with HMOA and the redness in thigh meat was also improved (p < 0.05). Additionally, supplementing LMOA increased (p < 0.05) the saturated fatty acids, unsaturated fatty acids and the ratio of polyunsaturated fatty acids to saturated fatty acids in breast meat. A positive effect occurred (p < 0.05) on jejunal villus height and ileal crypt depth in 21 d broilers supplemented with HMOA. Conclusion: Our findings indicated that dietary supplementation of MOA could improve the growth performance, meat quality, and fatty acids profile, as well as intestinal morphology. Furthermore, diets supplemented with mixed organic acids at 3000 mg/kg may be more desirable, considering the overall experimental results in broilers.

Dietary Supplementation of Carob and Whey Modulates Gut Morphology, Hemato-Biochemical Indices, and Antioxidant Biomarkers in Rabbits.

This study aimed to evaluate the influence of the carob powder (CP) and sweet whey powder (WhP) inclusion into weaning feed on the gut morphology, hemato-biochemical parameters, and antioxidant biomarkers. The addition of 10 g/kg (basal diet +10 g/kg of CP, of WhP) or the mixture (5 g/kg of CP and 5 g/kg of WhP) in the rabbit's standard diet was assessed. A total of 40 weaned New Zealand White rabbits (4 weeks old) was distributed according to body weight (BW) into four treatments (n = 10) and the feed additives were provided for 7 weeks. Tissue samples and blood were obtained after slaughter. Final BW, daily weight gain, feed conversion ratio, intestinal morphology, and carcass dressing were positively affected by CP-WhP treatments compared with the control diet. Also, CP-WhP treatments significantly increased total proteins, calcium and iron levels, fecal cholesterol excretion, total antioxidants capacity, superoxide dismutase, and catalase in different tissues and significantly decreased total cholesterol, triglycerides, and glucose in blood serum. These changes were associated with a diminution of blood tumor necrosis factor alpha, lipid peroxidation, and carbonyl proteins in rabbit tissues. Both the additives separately and especially in the mix may enhance productive performance, protein profile, gut function, immunity, and antioxidant activity, with reducing lipid peroxidation, essential inflammatory mediator, and protein-carbonyl residues of growing rabbits. These findings suggest that CP-WhP dietary supplementation provides novel insights into a variety of bioactive compound mixtures with different beneficial modes of actions.

The effects of cellulose and soybean hulls as sources of dietary fiber on the growth performance, organ growth, gut histomorphology, and nutrient digestibility of broiler chickens.

This study evaluated the effects of dietary fiber provided as purified cellulose (Solka-Floc, SF) or soybean hulls (SH) on the growth performance, organ growth, intestinal histomorphology, and nutrient digestibility. A total of 420 one-day-old Cobb male broilers were randomly assigned to 7 dietary treatments and reared to 20 d of age in battery cages (n = 6 replicates per treatment). The control group consisted of a simple corn and soybean-meal-based diet. The 6 fiber treatments had increasing amounts of SF or SH to achieve 4, 6, and 8% crude fiber (CF). Chromium oxide was added as an indigestible marker at 0.3% in all treatment diets from 14 to 20 d for nutrient digestibility analyses. Weights for digestive organs were taken on day 20. Growth performance was measured weekly. Birds fed 4% SH diet had a higher day 20 body weight gain than those fed 8% CF regardless of fiber sources (P = 0.0118). Control and 4% SH groups had the best feed conversion ratio among the treatments at 7, 14, and 20 d (P < 0.05). SH-containing diets had heavier relative gizzard and intestine weights (P < 0.001). Birds fed 8% SH diets had the highest duodenal villi height among the treatments (P < 0.001). Birds fed control and 4% SH had the highest jejunal villi height among the treatments (P < 0.001). Birds fed 4% SF and 4% SH had the highest ileal villi height among the treatments (P < 0.001). Dry matter digestibility was higher in 6% SF than in 8% SH (P = 0.0105). In general, birds fed high-SH diets had higher amino acid digestibility (P < 0.001). In conclusion, the study suggests that fiber type and inclusion level are crucial factors regulating intestinal development, nutrient digestion, and growth performance.

Influence of bacterial organic selenium on blood parameters, immune response, selenium retention and intestinal morphology of broiler chickens.

BACKGROUND: Several studies indicated that dietary organic selenium (Se) usually absorbed better than an inorganic source, with high retention and bioavailability. Dietary Se as an antioxidant element affects the immune system and hematological status in animals. Therefore, the aim of this study was to evaluate the effect of dietary supplementation of bacterial selenium as an organic source on hematology, immunity response, selenium retention, and gut morphology in broiler chickens. RESULTS: The present results revealed that supplementation of inorganic Se was associated with the lowest level of RBC, HB, and PCV with significant difference than ADS18-Se. In the starter stage, both T2 and T5 were associated with the significantly highest IgG level compared to the basal diet, while all supplemented groups showed higher IgM levels compared to the control group. In the finisher phase, all Se supplemented groups showed significant (P ˂ 0.05) increases in IgG, IgA, and IgM levels compared to T1. Birds fed bacterial-Se showed high intestinal villus height and better Se retention more than sodium selenite. The organic selenium of ADS18 had a superior action in improving Se retention compared to ADS1 and ADS2 bacterial Se. CONCLUSIONS: Bacterial organic Se had a beneficial effect on the villus height of small intestine led to high Se absorption and retention. Thus, it caused a better effect of Se on hematological parameters and immunity response.

Withania somnifera dietary supplementation improves lipid profile, intestinal histomorphology in healthy Nile tilapia (Oreochromis niloticus), and modulates cytokines response to Streptococcus infection.

Despite Withania somnifera (WS), stimulating effects have been investigated on many animal species, its role on lipid profile and intestinal histomorphology in healthy animals, and its modulating role on pro-inflammatory cytokines following infection in fish are yet scarce. In this context, lipid profile, liver, and intestinal histomorphology were measured in Nile tilapia fed with a basal diet or diets containing 2.5 and 5% of supplementary WS for 60 days. Besides, cytokines response was measured at 1, 3,7, and 14 days following Streptococcus iniae (S. iniae) infection after the feeding trial. All lipid profile parameters were nominally lowered, excluding high-density lipoprotein (HDL) that exhibited a significant increase in WS 5% group compared to other groups. Improved gut health integrity was observed, especially in WS 5% group in terms of increased goblet cell numbers, villous height, the width of lamina propria in all parts of the intestine, and a decrease in the diameter of the intestinal lumen of the distal intestine only. A significant down-regulation in the mRNA transcript level of cytokine genes (interleukin 1ß/IL-1ß, tumor necrosis factor α/TNFα, and interleukin 6/IL-6) was demonstrated in the kidney and spleen of WS-supplemented groups following S. iniae infection compared with the control infected (positive control/PC) group. Our findings give new insights for the potential roles of WS dietary inclusion not only on lipid profile and intestinal health integrity improvement in healthy fish under normal rearing but also as a prophylactic against the infection. Thus, WS can be incorporated as a promising nutraceutical in aquaculture.

Interactive effects of zinc and copper sources and phytase on growth performance, mineral digestibility, bone mineral concentrations, oxidative status, and gut morphology in nursery pigs.

This study investigated the interactive effects of zinc (Zn) and copper (Cu) sources and phytase on growth performance, oxidative status, mineral digestibility, tissue mineral concentrations, and gut morphology in nursery pigs. A total of 288 weaning barrows [body weight (BW) = 5.71 ± 0.81 kg], blocked by initial BW, were randomly allotted to one of eight dietary treatments, with nine pens per treatment and four pigs per pen. The eight dietary treatments were arranged in 2 × 2 × 2 factorial design, with two Zn sources [2,000, 2,000, and 100 mg/kg Zn from zinc oxide (ZnO) during phase 1 (days 1-14) and phase 2 (days 15-28), and phase 3 (days 29-42), respectively; 100 mg/kg Zn from zinc methionine hydroxy analogue chelate (Zn-MHAC) from phases 1 to 3], two Cu sources [150, 80, and 80 mg/kg Cu from copper sulfate (CuSO4) or copper methionine hydroxy analogue chelate (Cu-MHAC) during phases 1-3, respectively], and two phytase inclusion levels (0 or 500 FTU/kg). Results showed that ZnO supplementation at 2,000 mg/kg Zn significantly increased average daily feed intake (ADFI; P = 0.01) and average daily gain (ADG; P = 0.03) during phase 1 compared to Zn-MHAC group; however, Zn-MHAC supplementation tended (P = 0.06) to improve gain to feed ratio (G:F) during phase 2 compared to ZnO group. There were no differences (P > 0.10) between ZnO and Zn-MHAC groups in terms of ADG, ADFI, and G:F during the entire nursery period. Compared with CuSO4, Cu-MHAC tended to increase ADG (P = 0.07) and G:F (P = 0.08) during the entire nursery period. Phytase supplementation significantly increased ADG (P < 0.01), ADFI (P < 0.01), and G:F (P < 0.01) during the entire nursery period compared with no phytase supplementation. There was a significant interaction (P < 0.01) between Zn source and phytase on standardized total tract digestibility (STTD) of phosphorus (P), whereas there was no interaction (P = 0.21) between Cu sources and phytase on STTD of P. However, there was a significant interaction between Cu sources and phytase on calcium (Ca; P = 0.02) and P (P = 0.03) concentrations in metacarpal bones and G:F in phase 2 (P = 0.09). Furthermore, pigs fed diets containing Zn-MHAC tended to have lower ileum villus width (P = 0.07), compared with those fed diets containing ZnO, and pigs fed diets containing Cu-MHAC tended to have lower plasma malondialdehyde concentration (P = 0.10) compared with those fed diets containing CuSO4. In conclusion, under the conditions of the current study, ZnO supplementation at 2,000 mg/kg Zn was only effective in the first 2 wk postweaning, whereas Zn-MHAC supplementation at 100 mg/kg Zn could achieve better feed efficiency during phase 2 compared to pharmacological levels of ZnO, therefore, leading to no difference of growth performance in the entire nursery period. Low levels of Zn-MHAC may improve phytase efficacy on degrading phytate P compared to pharmacological levels of ZnO. Cu-MHAC may be more effective to promote growth compared to CuSO4, which may be partially driven by reduced oxidative stress. Results also indicated that Cu-MHAC might exert a synergistic effect with phytase on improving feed efficiency and bone mineralization.

A Comprehensive Evaluation of the Impact of Bovine Milk Containing Different Beta-Casein Profiles on Gut Health of Ageing Mice.

Ageing is often characterised by nutritional deficiencies and functional alterations of the digestive and immune system. The aim of the present study was to analyse the impact of consumption of conventional milk with A1/A2 beta-casein, compared to milk containing only the A2 beta-casein variant, characterised by a protein profile favouring gut health. Twenty-four ageing Balb-c mice (20 months old) were fed for 4 weeks, with either a control diet (CTRL), a diet supplemented with bovine milk containing A1/A2 beta-casein (A1A2) or a diet containing A2/A2 beta-casein (A2A2). Lymphocyte subpopulations, enzymatic activities, cytokine secretion, gut morphology and histopathological alterations were measured in different gut segments, while short-chain fatty acids (SCFAs) content and microbiota composition were evaluated in faecal samples. The A2A2 group showed higher content of faecal SCFAs (in particular, isobutyrate) of intestinal CD4+ and CD19+ lymphocytes in the intraepithelial compartment and improved villi tropism. The A1A2 group showed higher percentages of intestinal TCRγδ+ lymphocytes. Faecal microbiota identified Deferribacteriaceae and Desulfovibrionaceae as the most discriminant families for the A2A2 group, while Ruminococcaceae were associated to the A1A2 group. Taken together, these results suggest a positive role of milk, in particular when containing exclusively A2 beta-casein, on gut immunology and morphology of an ageing mice model.

Intestinal morphology, immunity and microbiota response to dietary fibers in largemouth bass, Micropterus salmoide.

This study is aimed at identifying the effects of dietary fiber on gut health, as well as the association between that understanding and fiber consumption in fish. A total of 300 juvenile largemouth bass (micropterus salmoides, initial average weight: 15.38 ± 0.16g) were randomly divided into three treatment groups (4 replicates per group). Fish were fed with isoproteic and isolipidic diets containing 0% (low fiber, LF), 4% (moderate fiber, MF) and 8% (high fiber, HF) soybean fiber, respectively. The intestine and intestinal content of test fish per treatment group after 56 days of treatment were sampled. The results showed that the anterior intestinal sections had normal histological architecture, and no considerable damage or inflammation was observed in any histological section from all subjects examined. Curiously, fish fed the MF diet had better histological alterations than the other treatments. Meanwhile, the intestinal antioxidant capacity in the MF group was significantly promoted when compared to the other groups, as well as up-regulated expression of antioxidant-related genes including sod, cat and gpx with increasing dietary fiber concentrations. Importantly, the administrations of MF diet remarkably elevated largemouth bass innate immune parameters include intestinal inducible nitric oxide synthase (iNOS) activity, nitric oxide (NO) and total protein content. Similarly, dietary administrations of fiber down-regulated notablely the expression of pro-inflammatory cytokines including IL-8, IL-1ß and TNFα, whereas up-regulated tolerogenic cytokine IL-10 and TGF-ß1 mRNA levels. In addition, dietary fibers also modulated the community structure of the intestinal microbiota by significantly altering bacterial diversity. Dietary supplemental fibers regulated intestinal microbiota in largemouth bass, characterized by a reduced abundance of Fusobacteria along with increased abundances of Proteobacteria and Firmicutes. Taken together, the present results suggested that moderate fiber supplementation was beneficial to promoting intestinal health status of fish through antioxidant and anti-inflammatory effects, which could be at least partially responsible by the modulation of gut microbial composition.

Interactive effects of threonine levels and protein source on growth performance and carcass traits, gut morphology, ileal digestibility of protein and amino acids, and immunity in broilers.

An experiment was executed to test the hypothesis that supplementation of dietary threonine (d-Thr), above NRC recommendation to diets containing poorly digestible protein source (PS) may compensate its detrimental effects on overall performance of broilers. In total, nine hundred 1-day-old mixed sex broilers (Ross-308) were randomly distributed over 6 (2 × 3) experimental diets comprising 5 replicates of 30 broilers each for 35 d. The experimental diets contain either soybean meal (SBM) or canola meal (CM) with 3 levels (100, 110, and 120% of NRC recommendation) of d-Thr. During the course of the trial (0 to 35 D), interactions (P < 0.05) between PS and d-Thr were observed for feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), carcass, and gut health parameters. The broilers fed recommended level (100%) of d-Thr had 7 and 5% poorer FCR compared with those fed diets with 110 and 120% d-Thr, respectively. For villus height (VH), an interaction (P = 0.007) was found between PS and d-Thr level. Broilers consuming SBM diets had 22% longer villi, 10% deeper crypts, and 30% greater VH to crypt depth ratio (VCR) compared to those fed CM. The broilers fed 110% d-Thr diets had 9% lower crypt depth (CD) and 15% greater VCR compared with those fed diets containing NRC recommended levels. CM resulted in 9% lower protein digestibility with lower (P < 0.05) of some AA, whereas it was improved by 7% in broilers fed 120% d-Thr supplemented diets. The bursa and spleen weights were positively affected (P < 0.001) by PS. Threonine supplementation (10%) resulted in 25% greater thymus, 18% heavier bursa, and 30% greater infectious bursal disease titer. In conclusion, supplementation of d-Thr, above NRC recommendation, resulted in a better growth performance and carcass traits, improved ileal digestibility of protein and amino acids, better gut health, and immunity in broilers.

Effects of inulin supplementation on intestinal barrier function and immunity in specific pathogen-free chickens with Salmonella infection.

We investigated the effects of inulin on intestinal barrier function and mucosal immunity in Salmonella enterica serovar Enteritidis (SE)-infected specific pathogen-free (SPF) chickens. SPF chickens (n = 240, 1-d-old) were divided into 4 groups (6 replicates per group, 10 chickens per replicate): a control group (CON) fed a basal diet without inulin supplementation and 3 SE-infected groups fed a basal diet supplemented with inulin 0% (SE group), 0.5% (0.5% InSE group), and 1% (1% InSE group), respectively. At 28 d of age, the chickens in SE-infected groups were orally infected with SE and in CON group were administrated with phosphated-buffered saline (PBS). Intestinal morphology, mucosal immunity, and intestinal barrier function-related gene expression were analyzed at 1- and 3-d post-infection (dpi). SE challenge significantly increased the mucosal gene expression, such as interleukin-1ß (IL-1ß), lipopolysaccharide-induced tumor necrosis factor factor (LITAF), interferon-γ (IFN-γ), and interleukin-6 (IL-6), and increased serum IFN-γ, secretory IgA (sIgA), and IgG concentration, and significantly decreased the gene expression levels of mucin 2 (MUC2) and claudin-1 at 3 dpi compared with the CON group (P < 0.05). Inulin supplementation improved the expression levels of these immunity- and intestinal barrier function-related genes, increased villus height (VH), and decreased crypt depth (CD) in the duodenum, jejunum, and ileum at 1 and 3 dpi within the SE-challenged groups (P < 0.05). SE challenge significantly increased ileal Toll-like receptor 4 (TLR4) mRNA at 1 and 3 dpi, suppressor of cytokine signaling 3 (SOCS3) mRNA at 1 dpi, and phospho-signal transducer and activator of transcription 3 (p-STAT3) and Janus kinase1 (JAK1) protein expression at 3 dpi compared with the CON group (P < 0.05). Inulin supplementation suppressed p-STAT3 and JAK1 protein expression and promoted ileal TLR4 and SOCS3 mRNA expression at 3 dpi compared with SE group (P < 0.05). In conclusion, inulin alleviated SE-induced gut injury by decreasing the proinflammatory response and enhancing mucosal immunity in chickens.