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1. This trial investigated the effect on embryo injected with ochratoxin A (OTA) and the growth performance, jejunal morphology and barrier of ducklings to 21 d old.2. Two hundred forty, fertilised eggs were individually weighed and randomly assigned to two groups, a control (CON) and the OTA treatment, according to average egg weight. On d 13 of embryonic development, the treatment group was injected with 8 ng OTA/g egg and the CON group was injected with NaHCO3 solution as a placebo. All newly hatched ducklings were assigned to the CON or OTA group based on the different treatments. Each treatment consisted of six replicates and each included 10 ducklings and the experiment lasted until 21 d of age.3. The results showed that embryos injected with OTA affected the 21 d body weight (BW) and average daily gain (ADG) of ducklings (p < 0.05). OTA exposure increased the relative weights of the liver, pancreas, gizzard, proventriculus and jejunum (p < 0.05); and decreased the relative length of the jejunum of ducklings (p < 0.05). Moreover, jejunal crypt depth increased (p < 0.05) and the villus height-to-crypt depth ratio (Vh/Cd) decreased in the OTA-injected group (p < 0.05). Compared with those in the CON group, the mRNA expression of Zonula Occludens-1; (ZO-1) (p = 0.0582) and Occludin; (p = 0.0687) in the OTA treatment group was downregulated.4. The findings demonstrated that a single low-dose injection of OTA increased body weight and daily gain in ducklings. Moreover, embryo exposure to OTA had negative effects with increased relative weight of organs and the jejunal crypt depth, decreased relative length of the intestine and mRNA expression of tight junctions (ZO-1, Occludin).

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Growth in chickens, especially meat-type chickens (broilers), is extremely rapid, but studies on the regulatory mechanism of intestinal glucose absorption with growth are few, contradictory, and unclear. Here, we investigated the regulation of intestinal glucose absorption with growth in broiler chickens using oral glucose gavage, intestinal Evans blue transit, intestinal glucose absorption, scanning electron microscopy, and glucose absorption- and cell junction-related gene expression analyses. Peak blood glucose levels after oral glucose gavage occurred at 10 and 50 min in chickens at 1 wk (C1W) and 5 wk (C5W) of age, respectively. The area under the curve for glucose levels was greater for the C5W than the C1W (P = 0.035). The stain ratio in the small intestine in the C5W was lower than that in the C1W (P = 0.01), but there were no differences in the tissue regions stained with Evans blue and the migration distance of Evans blue from Meckel's diverticulum. In everted sac and Ussing chamber experiments, we observed reduced intestinal glucose uptake and electrogenic glucose absorption in the jejunum of the C5W. Phloridzin, an inhibitor of sodium/glucose cotransporter 1 (SGLT1), suppressed the glucose-induced short-circuit current in the C1W (P = 0.016) but not the C5W. Although the addition of NaCl solution stimulated the glucose-induced short-circuit current in the C1W, no differences between the treatments were observed (P = 0.056), which was also the case in the C5W. Additionally, tissue conductance was diminished in the C5W compared with that in the C1W. Moreover, in the C5W, the intestinal tract was more developed and the jejunal villi were enlarged. In conclusion, glucose absorption throughout the intestine could be greater in C5W than in C1W; however, reduced SGLT1 sensitivity, decreased ion permeability, and intestinal overdevelopment lead to decreased local glucose absorption in the jejunum with growth in broiler chickens. These data provide a detailed analysis of intestinal glucose absorption in growing broiler chickens, and can contribute to the development of novel feeds.

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Sodium chloride (NaCl) is usually added to diets to meet the Na and Cl requirements of broilers in the Chinese poultry industry, but the optimal dietary NaCl supplemental level was not well-established. The present study was conducted to estimate the optimal dietary NaCl supplemental level of broilers fed a corn-soybean meal diet from 1 to 21 days of age. A total of 490, 1-day-old Arbor Acres male broilers were fed a NaCl-unsupplemented corn-soybean meal basal diet (control) and the basal diet supplemented with 0.10, 0.20, 0.30, 0.40, 0.50 or 0.60% NaCl for 21 days. Regression analysis was conducted to evaluate the optimal dietary NaCl level using the best fitted broken-line or asymptotic models. As dietary supplemental NaCl levels increased, average daily gain (ADG), average daily feed intake (ADFI), blood partial pressure of CO2, total CO2, base excess and anion gap, blood concentrations of HCO3, Na and Cl, serum Na concentration, jejunal villus height (VH) and tibia ash content increased linearly and quadratically (P < 0.05), while feed/gain ratio, relative weights of heart, liver and kidney, blood K concentration, serum concentrations of K, uric acid and glucose, and osmotic pressure decreased linearly and quadratically (P < 0.05). The estimates of optimal dietary NaCl levels were 0.20-0.22% based on the best fitted broken-line or asymptotic models (P < 0.0001) of ADG, ADFI and feed/gain ratio, and 0.08-0.24% based on the best fitted broken-line or asymptotic models (P < 0.0001) of blood gas indices, serum parameters, jejunal VH, tibia ash content and organ indices. These results suggested that the optimal dietary NaCl supplemental level would be 0.24% for broilers fed the corn-soybean meal diet from 1 to 21 days of age, which is lower than the current dietary NaCl supplemental level (0.30%) in the Chinese broiler production.

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This study was conducted to investigate the effects of Clostridium butyricum and Enterococcus faecalis on growth performance, immune function, inflammation-related pathways, and microflora community in weaned piglets challenged with lipopolysaccharide (LPS). One hundred and eighty 28-d-old weaned piglets were randomly divided into 3 treatments groups: piglets fed with a basal diet (Con), piglets fed with a basal diet containing 6 × 109 CFU C. butyricum·kg-1 (CB), and piglets fed with a basal diet containing 2 × 1010 CFU E. faecali·kg-1 (EF). At the end of trial, 1 pig was randomly selected from for each pen (6 pigs per treatment group) and these 18 piglets were orally challenged with LPS 25 µg·kg-1 body weight. The result showed that piglets fed C. butyricum and E. faecalis had greater final BW compared with the control piglets (P < 0.05). The C. butyricum and E. faecalis fed piglets had lower levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), IL-1ß, tumor inflammatory factor-α (TNF-α), and had greater level of serum interferon-γ (IFN-γ) than control piglets at 1.5 and 3 h after injection with LPS (P < 0.05). Furthermore, piglets in the C. butyricum or E. faecalis treatment groups had a greater ratio of jejunal villus height to crypt depth (V/C) compared with control piglets after challenge with LPS for 3 h (P < 0.05). Compared with the control treatment, the CB and EF treatments significantly decreased the expression of inflammation-related pathway factors (TLR4, MyD88, and NF-κB) after challenge with LPS for 3 h (P < 0.05). High-throughput sequencing revealed that C. butyricum and E. faecalis modulated bacterial diversity in the colon. The species richness and alpha diversity (Shannon) of bacterial samples in CB or EF piglets challenged with LPS were higher than those in LPS-challenged control piglets. Furthermore, the relative abundance of Bacteroidales-Rikenellanceae in the CB group was higher than that in the control group (P < 0.05), whereas EF piglets had a higher relative abundance of Lactobacillus amylovorus and Lactobacillus gasseri (P < 0.05). In conclusion, dietary supplementation with C. butyricum or E. faecalis promoted growth performance, improved immunity, relieved intestinal villus damage and inflammation, and optimized the intestinal flora in LPS-challenged weaned piglets.

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The aim of the study was to test two encapsulated regimens containing organic acids and/or zinc oxide (ZnO) on weaned piglet performance and jejunal mucosa morphology and immunity. For that, weaned piglets were allocated to treatments including control, supplemented with encapsulated organic acids (ACID group), and supplemented with organic acids and ZnO, both encapsulated (ACIDplus group). Antibiotics were used at similar concentrations in all groups during the first two weeks, but withdrawn from the ACIDplus group during the last three weeks of the experiment. ZnO was given with feed in the Control and ACID groups only during the first two weeks. The experimental period lasted 5 weeks. Piglets from the ACID group exhibited higher average daily gain compared to other groups during the last 3 weeks of the experiment (P<0.05). The ACIDplus group performed similarly with controls. The mucosal height of jejunum was higher in both ACID (P<0.01) and ACIDplus groups compared to controls (P<0.05). Immunohistochemical analysis of jejunal mucosa, showed higher numbers of neutrophils in ACID and ACIDplus groups compared to controls (P<0.01 and P<0.001, respectively). Treatments had the opposite effect on mucosal regulatory T-cells (Foxp3-positive cells) in jejunum, being higher (P<0.001) in control group compared to ACID and ACIDplus groups. The number of CD3-positive cells was higher (P<0.05) in the ACIDplus and control groups compared to the ACID group. In conclusion, the encapsulated products used had beneficial effects on growth performance coexisting with improvements on jejunal histomorphology and modulation of mucosal immunity.

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This study was conducted to investigate the effect of dietary supplementation of silymarin on performance, jejunal morphology and ileal bacterial population in broiler chicks intoxicated with a mix of aflatoxins. A total of three hundred thirty six 7-day-old Ross broiler chicks were randomly distributed between seven experimental groups with four replicates of 12 birds each. Experimental treatments consisted of a control group (unchallenged), and a 2 × 3 factorial arrangement, including two aflatoxin levels (0.5 and 2 ppm) and three levels of silymarin (0, 500 and 1000 ppm). Birds were challenged with a mix of aflatoxins from 7 to 28 days of age. Results showed that increasing aflatoxin level resulted in decreased average daily feed intake (ADFI) and weight gain (ADWG), consequently impaired feed conversion ratio (FCR) throughout the trial period. Dietary supplementation of silymarin resulted in the marked increases in ADFI and ADWG, and improved FCR values in aflatoxin-challenged chicks. Ileal bacterial populations at days 28 and 42 of age were increased by incremental levels of aflatoxins. On the other hand, dietary silymarin supplementation suppressed ileal populations of Escherichia coli, Salmonella, Klebsiella and total negative bacteria in aflatoxicated birds. Increase in dietary aflatoxin level resulted in the decreased villi height, villi height-to-crypt depth ratio (VH:CD), villi surface area and apparent villi absorptive area, while it increased crypt depth, goblet cell count and lymphoid follicular diameter. Feeding silymarin at the level of 1000 ppm increased villi height and VH:CD in aflatoxicated birds. Present results indicate that dietary inclusion of silymarin could improve performance by suppressing ileal bacteria and enhancing absorptive surface area in aflatoxin-challenged broiler chicks.

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This study was carried out to assess the effects of different levels of sanguinarine on antioxidant indices, immunological responses, serum biochemical parameters, ileal microbial counts and jejunal morphology of laying hens fed on diets with different levels of crude protein (CP). A total of 180 laying hens were subjected into nine dietary treatments with four cages of five birds each. Experimental treatments consisted of three levels of CP (85.0, 92.5 and 100% of Hy-Line W36 manual recommendation) and three levels of sanguinarine (0.00, 3.75 and 7.50 mg/kg) as a 3 × 3 factorial arrangement of laying hens which fed during a 70-day feeding trial. The in vitro study showed that sanguinarine exhibited sevenfold and threefold decreased antioxidant activities to inhibit 2-2-diphenyl-1-picric hydrazyl free radical as well as ferric ion reducing rather than butylated hydroxyl toluene. Although using the decremental levels of CP caused the increase in heterophil-to-lymphocyte ratio (p < 0.01), dietary administration of sanguinarine could suppress the serum cholesterol and malondialdehyde concentrations as well as heterophil-to-lymphocyte ratio (p < 0.05). Additionally, decreasing CP content resulted in the decreased percentage of albumin (p < 0.05); however, it had no negative effects on humoral immunity. Nonetheless, feeding of at least 3.75 mg/kg sanguinarine led to the remarkable increases in serum gamma globulin concentration (p < 0.01) and secondary (p < 0.05) antibody titres against sheep red blood cells. Moreover, a decline in dietary CP content led to higher villi height and crypt depth (p < 0.05; p < 0.001) and consequently decreased villi height-to-crypt depth ratio (p < 0.001) than the optimum level (100% CP). In spite of the effects of sanguinarine on the suppression of Escherichia coli and Salmonella counts (p < 0.05), it markedly enhanced villi height-to-crypt depth ratio as well as lamina propria lymphatic follicles extent, simultaneously (p < 0.001). Therefore, in spite of the detrimental effects of feeding low-CP diets on lymphocytes and serum albumin percentages, and villi height-to-crypt depth ratio, the administration of incremental levels of sanguinarine could improve cellular and humoral immunity, decrease ileal microbial counts and in turn improve the intestinal health indices in laying hens.

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An experiment was conducted to investigate the effects of dietary nanoselenium supplementation at 0, 0.6 and 1.2 mg/kg of diet on growth performance, serum biochemical parameters, immune response, antioxidant capacity, and jejunal morphology of 29-d-old male broilers subjected to heat stress at 37 ± 1°C for 14 d. Broilers were fed for 42 d on the experimental diets. The results showed that nanoselenium supplementation had no effect on growth performance, but it supplementation at the rate of 1.2 mg/kg diet decreased the serum concentration of cholesterol prior to the heat exposure. Further, dietary nanoselenium supplementation linearly increased the high-density lipoprotein cholesterol concentration, while linearly decreased those of low-density lipoprotein cholesterol and aspartate aminotransferase in the serum before applying heat stress. Compared with thermoneutral temperature, heat stress reduced body mass gain, feed intake, percentages of carcass, breast, leg, abdominal fat, bursa of Fabricius, thymus, antibody response against sheep red blood cells, serum concentration of protein, erythrocyte activities of glutathione peroxidase and superoxide dismutase, jejunal villus height, and villus height to crypt depth ratio, while increased feed conversion ratio, percentages of liver, gizzard, pancreas, gallbladder, heart, and the concentrations of aspartate aminotransferase and malondialdehyde. Dietary supplementation of nanoselenium linearly reduced the abdominal fat and liver percentages, while linearly increased the activity of glutathione peroxidase and villus height in heat-stressed broilers. Furthermore, the lower level of nanoselenium decreased the percentages of gizzard and heart in broilers under heat stress. The diet supplemented with 1.2 mg/kg nanoselenium improved feed conversion ratio and increased antibody response against sheep red blood cells, activity of superoxide dismutase, and villus height to crypt depth ratio, but decreased the serum concentrations of cholesterol, low-density lipoprotein cholesterol, and malondialdehyde in heat-stressed broilers. The results suggest that supplemental nanoselenium improved growth performance, internal organs health, immune response, and jejunal morphology by alleviating the oxidative stress induced by heat stress.

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