Combined supplementation with isochlorogenic acid and quercetagetin ameliorates dexamethasone-induced intestinal injury via attenuation of oxidative stress and inflammation

The aim of this study was to evaluate the effects of anti-stress agents on the growth performance and immune function of broilers under immune stress conditions induced by vaccination. A total of 128, 1-day-old Arbor Acres broilers were randomly divided into four groups. Group normal control (NC) was the control group. Group vaccination control (VC), T 0.5%, and T 1% were the treatment groups, which were nasally vaccinated with two doses of the Newcastle disease virus (NDV) vaccine. The chicks in groups T 0.5% and T 1% were fed conventional diets containing 0.5% and 1% anti-stress agents. Thereafter, these broilers were slaughtered on 1, 7, 14, and 21 days post-vaccination. The results indicated that anti-stress agents could significantly reduce serum adrenocorticotropic hormone (ACTH) (P < 0.01) and cortisol (CORT) (P < 0.05) levels, and improve the growth performance (P < 0.05) and immune function of broilers (P < 0.05); However, the levels of malondialdehyde (MDA) (P < 0.05) were decreased, and the decreased total antioxidant capacity (T-AOC) (P < 0.01) levels mediated by vaccination were markedly improved. In addition, anti-stress agents could attenuate apoptosis in spleen lymphocytes (P < 0.01) by upregulating the ratio of Bcl-2 to BAX (P < 0.01) and downregulating the expression of caspase-3 and -9 (P < 0.01), which might be attributed to the inhibition of the enzymatic activities of caspase-3 and -9 (P < 0.05). In conclusion, anti-stress agents may improve growth performance and immune function in broilers under immune-stress conditions. RESEARCH HIGHLIGHTS Investigation of effects and mechanism of immune stress induced by vaccination. Beneficial effect of anti-stress agents on growth performance, immune function, oxidative stress, and regulation of lymphocyte apoptosis. Demonstration of the effects of apoptosis on immune function in the organism.

Glutamine alleviates heat stress-induced impairment of intestinal morphology, intestinal inflammatory response, and barrier integrity in broilers

Chlorogenic acid protects against intestinal inflammation and injury by inactivating the mtDNA–cGAS–STING signaling pathway in broilers under necrotic enteritis challenge

Evaluation of stimbiotic on growth performance and intestinal development of broilers fed corn- or wheat-based diets

The aim of this study was to investigate the effects of aspirin eugenol ester (AEE) on ileal immune function in broilers under lipopolysaccharide (LPS)-induced immune stress. Two hundred and forty one-day-old male Arbor Acres chicks were randomly divided into four groups (saline, LPS, saline + AEE and LPS + AEE) with six replicates of ten broilers each. The saline group and LPS group were fed the normal diet, while the other two groups received normal diet plus 0.1 g/kg AEE. Broilers in the LPS and LPS + AEE groups were injected intraperitoneally with 0.5 mg/kg B.W LPS in saline for seven consecutive days beginning at 14 days of age, while broilers in the saline and saline + AEE groups were injected with saline only. The results showed that AEE improved the ileal morphology and increased the ratio of villus height to crypt depth of immune-stressed broilers. LPS-induced immune stress significantly reduced the expression of the genes for the tight junction proteins occludin, zonula occludens-1 (ZO-1), claudin-1 and claudin-2, in the ileum, while AEE significantly up-regulated the expression of these genes. Compared with the saline group, the LPS-treated chickens showed significantly increased mRNA expression of the inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), cyclooxygenase-2 (COX-2), and microsomal Prostaglandin E Synthesase-1 (mPGES-1) in the ileum, while they were significantly decreased by AEE supplementation. In addition, analysis of the ileal bacterial composition showed that compared with saline and LPS + AEE groups, the proportion of Firmicutes and Lactobacillus in the LPS group was lower, while the proportion of Proteobacteria and Escherichia-Shigella was higher. Similarly, Line Discriminant Analysis Effect Size (LEfSe) analysis showed that compared with the LPS group, Brevibacillus was dominant in the saline group, while the LPS + AEE group was rich in Rhizobium, Lachnoclostridium, Ruminococcaceae, Faecalibacterium, Negativibacillus, Oscillospiraceae, and Flavonifractor. These results indicate that dietary supplementation with 0.1 g/kg AEE could protect the intestinal health by improving the intestinal villus morphology, enhancing the expression of tight junction genes and alleviating inflammation to resist the immune stress caused by LPS stimulation in broilers, and the mechanism may involve COX-2-related signal transduction and improved intestinal microbiota composition.

The current study aimed to determine the impact of acidified feed on apparent ileal starch digestibility, intestinal transport and barrier function and intestinal glucose transporter expression. The experiment included a control group and a treatment group with broilers fed a standard diet without or with 1.5% of a commercial organic acid product (64% formic acid, 25% propionic acid, 11% water). Broilers were fed with the experimental diets from hatching until days 32-35. Starch digestibility was determined using 0.2% titanium dioxide as ingestible marker. Gene expressions of the intestinal sodium glucose transporter 1 (SGLT-1) and glucose transporter 2 (GLUT-2) were analysed using qPCR analysis. Additionally, SGLT-1 function and chloride secretion were analysed in Ussing chamber experiments. Jejunal samples were sequentially exposed to 10 mm glucose, 100 μm phloridzin, 100 μm histamine and 100 μm carbachol. Apparent ileal starch digestibility (±SEM) of the control group (97.5 ± 0.35%) and the acid-treated group (97.0 ± 0.59%) did not differ (p = 0.674). The mean tissue conductance of intestinal samples obtained from the control group and the treatment group was similar [10.6 mS/cm(2) (±0.68) and 9.4 mS/cm(2) (±0.80) respectively (p = 0.147)]. The mean short-circuit currents (ΔIsc ) of the samples exposed to glucose, phloridzin, histamine and carbachol did not differ (p > 0.05). Additionally, no differences in the expression of SGLT-1 and GLUT-2 could be observed (p = 0.942, p = 0.413). Based on this study, the consumption of feed supplemented with organic acids was not associated with effects on ileal starch digestibility and functional traits of jejunal tissues, indicating that these additives have no major impact on the small intestinal function in broilers.

Effect of chronic hypoxia on the pulmonary arterial blood pressure of the chicken

Effects of hesperidin, thymol, rosmarinic acid and their combined effect on growth performance, intestinal barrier function and cecal microbiota in broilers

This experiment aimed to investigate the effects of bacteria-enzyme co-fermented Chinese herbal medicine on growth performance, apparent nutrient digestibility, meat quality, and immune function in broilers. Four hundred one-day-old, uniformly healthy Arbor Acres broiler chicks were randomly divided into 5 groups with 8 replicates of 10 chicks each. Using a single-factor randomized design, the control group received a basal diet, the unfermented herbs group received the basal diet supplemented with 1% unfermented Chinese herbal medicine, and three treatment groups received the basal diet supplemented with 0.5, 1, and 1.5% bacteria-enzyme co-fermented Chinese herbal medicine, respectively. The feeding trial lasted 42 days. Upon completion, three broilers were randomly selected from each replicate for a 4-day metabolism trial to determine apparent nutrient digestibility. Results showed that compared to the control group, the final body weight and average daily gain were significantly increased (p < 0.05), and the feed-to-gain ratio was significantly decreased (p < 0.05) in the groups supplemented with 1 and 1.5% co-fermented herbs. The apparent digestibility of dry matter, crude ash, and gross energy was significantly higher (p < 0.05) in the 1 and 1.5% co-fermented herbs groups than in the control group. All three co-fermented herbs supplementation groups exhibited significantly higher apparent digestibility of crude protein, ether extract, and crude fiber compared to the control group (p < 0.05). Breast muscle drip loss and shear force were significantly reduced (p < 0.05) in the 1 and 1.5% co-fermented herbs groups compared to the control, with no significant difference between these two groups (p > 0.05). All herbs-supplemented groups showed significantly higher serum IgA, IgG, and IL-2 levels and significantly lower IL-1β levels than the control group (p < 0.05). In conclusion, supplementing Arbor Acres broiler diets with bacteria-enzyme co-fermented Chinese herbal medicine effectively enhanced growth performance and apparent nutrient digestibility, improved meat quality, and boosted immune function. Comprehensive consideration suggests that the recommended inclusion level of bacteria-enzyme co-fermented Chinese herbal medicine in Arbor Acres broiler diets under this experimental condition is 1%.

Effects of yucca extract (YE) on feed efficiency, immune and antioxidative function in Arbor Acres broilers were studied. One hundred and twenty-eight fourteen-day-old broiler chickens were randomly divided into four treatments with four replicates of 8 birds each. These four diets were formulated by adding 0, 100, 200 and 300 mg/kg YE to the basal diet. The results showed that: diets supplemented with 100 and 200 mg/kg YE increased average body weight gain, feed efficiency, IgG, IgM, T-AOC, CAT and SOD levels, and have positive effects on inducing immune organs' maturation. In addition, 100 mg treatment mainly improved the feed efficiency whereas 200 mg treatment mainly acted on immunity and anti-oxidation. In conclusion, YE can be used as a feed additive due to its capability to improve feed efficiency, immune and antioxidative function in broilers.

This study was conducted to investigate the effects of Artemisia annua L. aqueous extract (AAE) on intestinal immune and antioxidative function of broilers. A total of 200 one-day-old Arbor Acre broilers were randomly allotted into five dietary treatment groups, with five replicates per treatment and eight broilers per replicate. The five treatment diets were formulated by adding, respectively, 0 (control group), 0.5, 1.0, 1.5, and 2.0 g/kg AAE in the basal diet. The results showed that dietary inclusion of AAE quadratically decreased interleukin (IL)-1β content, linearly decreased IL-6 content in the small intestine through regulating the nuclear factor-kappa B signal pathway, and quadratically increased immunoglobulin (Ig)M and sIgA content in ileum and jejunum. Besides, there was a quadratic decrease in the gene expression of IL-1β, IL-6, and toll like receptor 4 (TLR4) in ileum on day 21, and the gene expression of IL-6 and TLR4 in duodenum on day 42, thereby improving small intestinal immune function in broilers. Additionally, dietary inclusion of AAE improves antioxidative function through the nuclear factor-erythroid 2-related factor 2 (Nrf2) signal pathway in the small intestinal mucosa of broilers, especially, quadratically increased catalase (CAT) and superoxidase dismutase activity in ileum, and total antioxidant capacity and glutathione peroxidase activity in duodenum, and quadratically decreased malondialdehyde concentration in ileum, besides, linearly increased heme oxygenase-1 and Nrf2 gene expression in jejunum and ileum on day 42, quadratically increased CAT gene expression in the small intestine. Furthermore, regression analyses of the above parameters showed that the optimal dose range of AAE in the diet of broilers was 1.12–1.38 g/kg.

This study aimed to investigate the effects of dietary zinc-loaded montmorillonite (Zn-MMT) on performance, Zn transporter expression, metal deposition, antioxidant capacity, and intestinal function in broilers. A total of 144 one-day-old male Cobb broilers were randomly divided into three treatment groups. The broilers in the control group (CK) were fed a corn–soybean meal basal diet, while the experimental groups were fed a basal diet supplemented with 40 mg/kg Zn-MMT and ZnSO4 (in terms of Zn content). The results showed that Zn-MMT had no significant (p > 0.05) effect on average daily gain (ADG), average daily feed intake (ADFI), or carcass parameters, but it significantly (p < 0.05) reduced the feed-to-gain (F: G) ratio. Dietary Zn supplementation increased (p < 0.05) the expression of Zn transporter 1 (ZnT-1), Zn transporter 5 (ZnT-5), metallothionein (MT), and MTF-1 mRNA in the jejunum and the Zn content in the tibia and whole blood. In addition, it increased (p < 0.05) total antioxidant capacity (T-AOC) and Cu/Zn-SOD while reducing (p < 0.05) malondialdehyde (MDA) levels in the liver and jejunum. However, no significant effect (p > 0.05) was observed on the microbial population in the cecum. Furthermore, compared to the CK and ZnSO4 groups, Zn-MMT significantly (p < 0.05) increased the mRNA expression of MT-3 and divalent metal transporter 1 (DMT-1) in the jejunum and promoted the storage of Zn in the liver and pancreas. It also significantly (p < 0.05) increased villus height (VH) and the villus heightto-crypt depth (VH/CD) ratio in the duodenum and jejunum, increased the VH/CD ratio in the ileum, and reduced CD in the duodenum. In conclusion, supplementation with Zn-MMT in a corn–soybean meal basal diet can increase the expression of metal transporters, promote Zn deposition, enhance antioxidant capacity, improve intestinal tissue parameters, and increase Zn utilization.

To investigate the effects of Bacillus coagulans (BC) and tributyrin (TB) on Danzhou chickens, a 2 × 2 factorial design was adopted. A total of 480 chickens were randomly assigned to four dietary treatments, consisting of two BC levels (0 and 1.5 g/kg) and two TB levels (0 and 1.0 g/kg), for a 35-day trial. The results showed that supplementation with BC or TB alone significantly increased the average daily gain (ADG), serum immune parameters (immunoglobulin A, immunoglobulin G, and anti-inflammatory cytokines interleukin-4 and interleukin-10), total antioxidant capacity, and catalase activity, while reducing pro-inflammatory cytokine levels and the feed-to-gain ratio (p < 0.05). In addition, individual supplementation with BC or TB also enhanced digestive enzyme activities in the intestine, increased villus height in the small intestine, and optimized the structure of the cecal microbiota (p < 0.05). More importantly, significant synergistic interactions between BC and TB were observed across multiple parameters (p < 0.05). Combined supplementation further increased ADG, serum immunoglobulin M levels, superoxide dismutase activity, lipase activity in the ileum, and villus height in the jejunum (p < 0.05). Meanwhile, the combined supplementation also significantly elevated the abundance of beneficial bacteria such as Bacteroides, Eubacterium_brachy_group, and Negativibacillus. In conclusion, supplementation with BC or TB effectively improved the growth performance, antioxidant status, immune function, intestinal morphology, and cecal microbiota composition of Danzhou chickens, and the combined supplementation demonstrated superior effects compared to individual supplementation.

This study investigated the effects of Glycyrrhiza uralensis extract (GUE), Lactobacillus acidophilus (Lac), and their combination on production performance, immune and antioxidant functions, and intestinal health in broilers. A total of 420 one-day-old male Liangfenghua broilers were randomly assigned to four groups and fed with basal diet, GUE diet with 0.1% GUE, Lac diet with 4.5 × 10⁷ CFU/kg Lac, or GUE+Lac diet with 0.1% GUE and 4.5 × 10⁷ CFU/kg Lac. The experiment lasted 84 days. The results demonstrated that both GUE and Lac enhanced health by increasing immune organ indices, serum levels of IFN-γ, IL-2, IgA, and IgG, and activities of GSH-Px and SOD (p < 0.05). They also improved intestinal morphology and barrier function by increasing villus height and the villus height to crypt depth ratio (VH/CD), upregulating expression of Zonula occludens-1 (ZO-1), mucin-2 (MUC2), and Occludin (OCLN), and reducing expression of IL-1β, TLR4, and TNF-α (p < 0.05), which increased nutrient metabolic rates (p < 0.05). These changes ultimately resulted in improved production performance, evidenced by increased body weight and decreased abdominal fat rate (p < 0.05). Notably, the combined GUE+Lac exhibited positive synergistic effects, leading to enhanced immune function as shown by increased serum levels of IL-2, IFN-γ, IgA, and IgG; improved antioxidant capacity indicated by elevated GSH-Px activity in serum and liver; and enhanced intestinal morphology and barrier function by increased villus height and VH/CD ratio, upregulated expression of ZO-1, MUC2, and OCLN, and reduced expression of IL-1β and TLR4, TNF-α (p < 0.05) compared to both GUE and Lac alone. This synergism between GUE and Lac significantly increased body weight and nutrient metabolic rates while decreasing abdominal fat rate in broilers. Altogether, we demonstrated the synergistic enhancement of production performance, immunity, antioxidation and intestinal health in broilers by combining GUE and Lactobacillus acidophilus. These findings provide robust scientific support for the future development and application of feed additive.

Dietary zinc oxide nanoparticle (ZnO NP) possessing multiple biological activities might be a potential substitute for the combination of ZnSO4 and antibiotic growth promoter in broiler diets. Therefore, this study was conducted to investigate the efficacy of dietary ZnO NP as a substitute to the combination of ZnSO4 and xanthomycin for growth, antioxidant capacity, immunity, intestinal barrier and liver function in broilers. Arbor Acres chicks (n = 320) were assigned to 5 treatments with 8 replicates. Birds received a basal diet supplemented with 80 mg/kg ZnSO4 plus 5 mg/kg xanthomycin (ZnSO4 + Xanthomycin) or 0 (negative control, NC), 40, 80, and 160 mg/kg ZnO NP for 42 days. The average daily gain, average daily feed intake and feed-to-gain ratio showed dose-dependent increases with the increasing level of dietary ZnO NP during the 21–42 day and 1–42 day stages. The final body weight (42 d) and serum concentrations of insulin-like growth factor 1 and growth hormone increased linearly with the increasing level of dietary ZnO NP. In addition, 80 mg/kg ZnO NP increased the serum concentrations of IgA, IgG, IgM, andinterleukin-10 and peroxidase activity, the jejunal mucosal villus height, villus width and goblet cell numbers. Dietary 80 or 160 mg/kg ZnO NP significantly altered mRNA abundances of genes related to antioxidant status, intestinal barrier and immunity in the jejunal mucosa. These results indicated that dietary supplementation with 40–160 mg/kg ZnO NP caused no obvious negative effects on liver function, but effectively improved growth performance, intestinal barrier function, immunity and antioxidant capacity. Highlights Dietary 40–160 mg/kg zinc oxide nanoparticle (ZnO NP) improved growth performance and enhanced immunity of broilers without obvious negative effects on liver function. Dietary 40–160 mg/kg ZnO NP improved intestinal barrier and intestinal morphology, and enhanced antioxidant capacity via Nrf2/HO-1 pathway. Doses of 40–80 mg/kg ZnO NP were suggested to alternate the combination of 80 mg/kg ZnSO4 and 5 mg/kg xanthomycin in diets of broilers.