Bacillus amyloliquefaciens supplementation alleviates immunological stress in lipopolysaccharide-challenged broilers at early age

Zinc Glycine supplementation improves bone quality in meat geese by modulating gut microbiota, SCFA's, and gut barrier function through Wnt10b/NF-κB axis

Bone disorders are characterized by leg abnormalities and alterations in gut microbiota, which are linked with destruction of bone structure and increased risk of fractures. Zinc (Zn) plays a crucial role in normal bone homeostasis and has been proven to be highly effective against leg problems. The effects of different Zn sources on bone quality were evaluated in this study. A total of 300 one-d-old Wanpu mixed-sexed geese fed 2 basal diets added with best suited levels of 80 mg/kg inorganic zinc (ZnSO4), and 80 mg/kg Organic zinc (Zn-Glycine) for 60 d. Tibia bone mineral density (BMD), ash percentage, and tibia length increased with dietary Zn source (P < 0.05). Micro-computed tomography analysis revealed that Zn-Glycine improved bone mass, potentially due to an increased abundance of Firmicutes and higher SCFA production in the cecum. Dietary Zn Glycine addition reduced intestinal permeability, upregulated the protein expression of tight junction protein (Zonula Occludens-1, Claudin-1), downregulated diamine oxidase (DAO) levels, and increased the abundance of Lactobacillus and Bifidobacterium, which was accompanied by a reduction in inflammatory cytokines levels in the serum, tibia, and cecum. In terms of bone turnover, Zn-Glycine increased alkaline phosphatase (ALP) and other bone markers (Runt-related transcription factor 2- Runx2, Osteoprotegerin- OPG, Osteocalcin- OCN, Suppressor of mother against decapentaplegic- SMAD) expression, resulting in a decrease in osteoclast number and a reduction in serum bone resorption biomarkers, including serum tartrate-resistant acid phosphatase activity and tibia nuclear factor of activated T-cells (NFATC1) and tumor necrosis factor receptor associated factor 6 (TRAF-6) (P < 0.05). Zn-Glycine also enhanced antioxidant capacity by increasing catalase (CAT) and glutathione peroxidase (GSH-PX), resulting in reduced reactive oxygen species (ROS) and malondialdehyde (MDA) production (P<0.05). Zn-Glycine at 80mg/kg in the diet actively reduced (P<0.05) the expression of cell-death-associated proteins (Beclin-1, Caspase-3). Additionally, Zn-Glycine improved intestinal morphology (villus height, villus-to-crypt ratio), supporting efficient nutrient absorption. Immunofluorescence analysis of tibia showed higher expression of wingless type-10b (Wnt-10b) and reduced expression of nuclear factor-kappa B (NF-κB) in Zn-Glycine group compared to ZnSO4 group. These findings underscore the significance of the gut-bone axis and provide new insights into the effect of Zn-Glycine on bone health in meat geese through a key signaling pathway.

Betaine enhances hepatic antioxidant activity and thymus-associated immunity in lipopolysaccharide-challenged goslings

BACKGROUND

Betaine is an effective antioxidant and lipopolysaccharide (LPS) is an inflammatory stimulus that can disrupt the antioxidant system. However, the precise mechanisms of betaine's antioxidant activity remain undetermined. This study aimed to examine the impact of betaine on growth, antioxidant capacity, and inflammatory cytokine production in LPS-challenged goslings. In this study, 168 healthy Jiangnan White Goslings (males, 15 days old) were selected and randomly categorized into four groups. There were 7 goslings per replicate and 6 replicates for each treatment. This study employed a 2 × 2 factorial arrangement, the goslings were provided a diet containing 0% or 0.06% betaine and were injected with physiological saline or LPS.

RESULTS

Subsequent analyses revealed that on day 21 of LPS treatment, there was a significant decrease in gosling's ADFI, ADG, and BW, whereas dietary betaine supplementation improved ADFI and BW in LPS-stressed individuals (p = 0.08, p = 0.09). LPS challenge significantly upregulated pro-inflammatory interleukin-1β (IL-1β) mRNA (p < 0.05), whereas betaine significantly lowered these levels (p < 0.05). During the LPS stress period (days 16-21), the superoxide dismutase (SOD) activity and total antioxidant capacity (T-AOC) were significantly reduced, while malondialdehyde (MDA) levels were increased in the liver and jejunal mucosa (p < 0.05). Betaine administration reversed these changes and significantly increased SOD and T-AOC levels while decreasing the MDA content (p < 0.05). However, both LPS and betaine did not affect the mRNA levels of SOD1 or glutathione peroxidase 4 (GSH-Px4) in the liver or jejunal mucosa during the stress (days 16-21) or recovery (days 22-28) periods.

CONCLUSIONS

In summary, these analyses revealed that dietary betaine administration can effectively abrogate LPS-induced oxidative liver damage.

Protective effects of carnosic acid on growth performance, intestinal barrier, and cecal microbiota in yellow-feathered broilers under lipopolysaccharide challenge

This research was performed to investigate protective effects of carnosic acid on growth performance, intestinal barrier, and cecal microbiota of lipopolysaccharide-challenged broilers. Three hundred 1-day-old yellow-feathered broilers (male) were allocated randomly into 5 treatments, with 6 replicates per treatment, and 10 birds per replicate cage. Birds in both the control group (CON) and the lipopolysaccharide-challenged group were provided with a basal diet, while others were fed a basal diet supplemented with 20, 40, and 60 mg/kg carnosic acid (CA20, CA40, CA60), respectively. At 17, 19, and 21 days of age, birds were injected intraperitoneally with lipopolysaccharide (500 μg/kg body weight), except those in CON, which were injected with saline. Compared with challenged birds, the CA20, CA40, and CA60 increased (P < 0.05) the final body weight, average daily gain, and average daily feed intake, and the CA40 and CA60 also decreased diarrhea rate. Compared with challenged birds, carnosic acid reduced (P < 0.05) plasmal levels of D-lactic acid and endotoxin, increased (P < 0.05) the villus height to crypt depth ratio, and the number of goblet cells in duodenum. The CA40 and CA60 elevated (P < 0.05) relative expression of cell junction proteins (Claudin-1/-2 and ZO-1/-2/-3) and MUC-2 in duodenum, while decreased (P < 0.05) relative expression of TLR2, TLR4, and the concentrations of IL-6, IL-10, TNF-α, TGF-β1 in duodenum. CA40 also increased (P < 0.05) the α-diversity of the cecal microbiota and boosted (P < 0.05) the relative abundance of beneficial phyla and genera, particularly Firmicutes, Anaerofilum, and Papilibacter. In conclusion, dietary supplementation with carnosic acid showed protective effects on the growth performance and intestinal health in challenged broilers by down-regulating the expression of TLRs (TLR2/4) and inhibiting the production of inflammatory cytokines, strengthening the tight junction in intestinal epithelial cells, and enhancing the diversity of microbiota and the relative abundance of beneficial bacteria. When supplemented to diet of broilers, 40 mg/kg carnosic acid was recommended.

Effects of Different Levels of Lycium barbarum Flavonoids on Growth Performance, Immunity, Intestinal Barrier and Antioxidant Capacity of Meat Ducks

Background: In vitro findings on the biological functions of Lycium barbarum flavonoids (LBFs) as feed additives are limited. This study aimed to explore the effects of different concentrations of LBFs on the growth performance, immune function, intestinal barrier, and antioxidant capacity of meat ducks. A total of 240 one-day-old male meat ducks were randomly allocated to four groups, each receiving a basal diet supplemented with 0 (control), 250, 500, or 1000 mg/kg of LBFs for 42 d. Results: The results showed that dietary supplementation with 500 mg/kg of LBFs resulted in a significant increase in average daily feed intake, body weight, average daily gain, and feed conversion ratio. Dietary supplementation with 500 or 1000 mg/kg of LBFs resulted in significant decreases in serum levels of D-lactic acid and lipopolysaccharide. Dietary supplementation with 500 mg/kg LBFs significantly decreased diamine oxidase activity and enhanced the activities of catalase, total antioxidant capacity, and glutathione peroxidase in the jejunal mucosa, as well as the activity of total superoxide dismutase and the content of glutathione in the ileal mucosa, while significantly lowering the content of malondialdehyde in the ileal mucosa. Dietary supplementation with 500 mg/kg LBFs significantly up-regulated the mRNA expression of genes associated with intestinal barrier function and antioxidant capacity in the jejunal and ileal mucosa, as well as the protein expression of these antioxidant genes, and led to a significant reduction in the mRNA expression of pro-apoptotic and inflammatory-related genes. Conclusions: The addition of LBFs to the diet improved the growth performance, intestinal barrier function, immune response, and antioxidant capacity of the ducks, which may be closely associated with the activation of the Nrf2 signaling pathway and the inhibition of the NF-κB signaling pathway. The optimal dietary inclusion level of LBFs in ducks was 500 mg/kg.

Effect of lipopolysaccharides from pathogenic bacteria on broiler chickens' productivity: a meta-analysis

1. This meta-analysis investigated the impact of LPS and covariates (serotype, rearing period and administration route) on the productivity parameters of broiler chickens (average daily feed intake (ADFI), average daily gain (ADG) and feed conversion ratio (FCR)).2. Thirty-two eligible studies were included. Hedges' g effect size was determined using a random-effects model at 95% confidence interval.3. Results showed that LPS significantly decreased average daily feed intake (ADFI; p < 0.0001) and average daily gain (ADG; p < 0.0001) and increased FCR (p < 0.0001). The serotypes Escherichia coli 055: B5 (EC055: B5) and Escherichia coli 0127: B8 (EC 0127: B8) significantly reduced ADFI and ADG, and the serotype EC 055: B5 significantly increased the FCR (p < 0.05).4. The intraperitoneal administration of the LPS significantly reduced the productivity of broiler chickens (p < 0.05), but other administration routes did not show such effects. The reduction in ADFI and ADG was found in all rearing periods (p < 0.05), and the increase in FCR was observed in the starter (p = 0.0302) and grower periods (p = 0.0031).5. Exposure to LPS significantly reduced the productivity of broiler chickens (p < 0.05). However, no relationship was observed between LPS dosage and productivity as indicated by the meta-regression study.6. The findings indicated that LPS has detrimental effects on broiler chickens' ADFI, ADG and FCR across various LPS serotypes and rearing periods. These detrimental impacts of LPS remain consistent regardless of the administered dosage.

The impact of dietary supplementation of Quercetagetin on growth, antioxidant capacity, and gut microbiota of diquat-challenged broilers

This experiment aimed to investigate the effects of Quercetagetin (QG) on the growth performance, antioxidant capacity, and cecal microbiota of broilers. Two hundred and forty 21-day-old WOD168 broilers with similar body weights were randomly divided into five groups of six replicates each with eight chickens. The control group was fed a basal diet composed of corn and soybean meal, while the experimental groups received basal diets supplemented with 0, 10, 20, and 40 mg/kg QG, along with intraperitoneal injection of 20 mg/kg body weight Diquat (DQ). The experiment lasted for 21 days. The results showed that: (1) QG significantly alleviated the decrease in average daily feed intake and average daily gain induced by Diquat, reduced the elevation of serum ACTH content, and significantly increased GH content (P < 0.05); (2) QG supplementation significantly mitigated the decrease in serum CAT activity and duodenal GSH-Px activity induced by Diquat (P < 0.05), as well as the increase in MDA content (P < 0.05); additionally, QG significantly increased the gene expression levels of GSH-Px, Nrf2, and Keap1 (P < 0.05); (3) Alpha and Beta diversity analysis revealed that QG supplementation significantly increased the cecal microbial OTUs and Chao1 index of broilers (P < 0.05). At the phylum level, compared with the Diquat group, the LQG group significantly decreased the relative abundance of Firmicutes (P < 0.05) and significantly increased the relative abundance of Bacteroidota (P < 0.05). At the genus level, compared with the CON group, the Diquat group significantly decreased the abundance of Lactobacillus and Alistipes (P < 0.05), while QG supplementation significantly alleviated the decrease in the abundance of Lactobacillus and Alistipes (P < 0.05). In conclusion, the addition of an appropriate amount (20 mg/kg) of QG to the diet can promote the growth of broilers, enhance antioxidant capacity, and improve intestinal health.

Effect of supplementation with Lactobacillus rhamnosus GG powder on intestinal and liver damage in broiler chickens challenged by lipopolysaccharide

This study explores the effect of dietary along with Lactobacillus rhamnosus GG (LGG) powder on intestinal and liver damage in broiler chickens challenged by lipopolysaccharide (LPS). A total of 100 healthy 1-day-old Ross 308 broiler chickens were selected and randomly divided into two treatments: the control group and the LGG treatment group. There were five replicates for each group, with 10 chickens per replicate. The chickens in the control group were fed a basal diet, while LGG treatment was supplemented with 1,000 mg/kg LGG along with the basal diet. The experiment lasted 29 days, and the trial included two phases. During the first 27 days, the animals were weighed on the 14th and 27th days to calculate growth performance. Then, on day 29, 2 animals from each replicate were intraperitoneally injected with 1 mg/kg BW LPS, and another 2 animals were treated with an equal volume of saline. The chickens were slaughtered 3 h later for sampling and further analysis. (1) LGG addition to the diet did not affect growth performance, including average daily gain (ADG), average daily feed intake (ADFI), and feed-to-weight ratio (F/G) of broiler chickens; (2) LPS stimulation decreased villus height (VH), and caused oxidative stress and increased the amount of diamine oxidase (DAO) in plasma, and the relative expression of intestinal inflammation genes (interleukin-8 [IL-8], interleukin 1β [IL-1β], inducible nitric oxide synthase [iNOS], and tumor necrosis factor-α [TNF-α]) and the relative expression of liver injury genes (b-cell lymphoma 2 [BCL2], heat shock protein70 [HSP70], and matrix metallopeptidase 13 [MMP13]). (3) Supplementation of LGG increased VH and the relative expression of intestinal barrier genes (mucins 2 [Mucin2] and occludin [Occludin]) and decreased the amount of DAO in plasma and the relative expression of intestinal inflammatory factors (IL-8, iNOS, and IL-1β). LGG supplementation also increased the expression of liver injury-related genes (MMP13 and MMP9). In conclusion, LGG enhanced intestinal barrier function, improved intestinal morphology, and alleviated the intestines' inflammatory response in LPS-stimulated broiler chicken, and it has a slightly protective effect on liver damage.

Effects of Cashew Nuts (Anacardium occidentale L.) and Cashew Nut Oil on Intestinal Permeability and Inflammatory Markers during an Energy-Restricted 8-Week Intervention: A Randomized Controlled Trial (Brazilian Nuts Study)

Cashew nuts can contribute to improving intestinal permeability and inflammation as they contain essential nutrients and bioactive compounds, but no clinical trials have evaluated these potential effects. This randomized trial aimed to assess the effects of cashew nuts and their oil on intestinal permeability and inflammatory markers. Sixty-four adults with overweight or obesity were allocated into three groups receiving energy restriction (-500 kcal/day): control (CT, free nuts), cashew nuts (CN, 30 g/day), or cashew nut oil (OL, 30 mL/day). Urine lactulose and mannitol, plasma zonulin and the lipopolysaccharide-binding protein (LBP), plasma interleukins (IL-6, TNF-α, IL-10, IL-1β, IL-8, and IL-12p70), and C-reactive proteins were analyzed. Energy restriction reduced body fat and other indicators of adiposity without differences between the groups. Only the control group increased LBPs after an 8-week intervention. There were no statistically significant differences found between the groups in terms of intestinal permeability and inflammatory markers. In conclusion, incorporating cashew nuts or cashew nut oil into an energy-restricted 8-week dietary intervention did not change intestinal permeability and inflammatory markers. As studies evaluating cashew nuts on these markers remain scarce, further research is needed, perhaps with a longer study period and a higher concentration of cashew nuts and oil.

Effects of a Combined Chinese Herbal Medicine on Growth Performance, Intestinal Barrier Function, Immune Response, and Cecal Microflora in Broilers Infected with Salmonella enteritidis

This study investigated the effects of CCHM in drinking water on broilers infected with Salmonella enteritidis. One-day-old male Cobb 500 broilers (n = 300) were randomly assigned to five groups: a control (NC) group, a Salmonella enteritidis challenge (SE) group, an antibiotic (AB) group, a low dose of CCHM (CL) group, and a high dose of CCHM (CH) group. Each group had six replicate cages with ten broilers per cage. The broilers in the NC and SE groups were given normal drinking water. From days 12 to 18, the AB group received water treated with ciprofloxacin lactate injection (1 mL/L), while the CL and CH groups received water containing CCHM at doses of 5 mL/L and 10 mL/L, respectively. Broilers in all groups except the NC group were orally given Salmonella enteritidis daily from days 9 to 11. The experimental period was 28 days. The results showed that, compared with the SE group, the CL and CH groups showed improved growth performance; increased immune organ indices, expressions of ileal occludin and ZO-1 proteins, jejunal and ileal villus heights (except at day 19), and cecal Lactobacillus counts on days 19 and 28 (p < 0.05); and decreased jejunal and ileal lesion scores, ileal interleukin 1β (IL-1β) (except at day 19), interferon-γ (IFN-γ), interleukin 6 (IL-6) (except at day 19), secretory immunoglobulin A (slgA) and tumor necrosis factor α (TNF-α) (except at day 19) levels, serum D-lactic acid and diamine oxidase (DAO) (except at day 19) contents, jejunal and ileal crypt depths (except at day 19), and cecal Salmonella and Escherichia coli counts on days 19 and 28 (p < 0.05). On day 28, except for the levels of ileal interleukin 10 (IL-10), TNF-α, slgA, and serum D-lactic acid content, there were no differences among the NC, AB, and CL groups (p > 0.05). In conclusion, drinking water supplemented with CCHM alleviated the intestinal damage caused by Salmonella enteritidis infection and improved growth performance and cecal microbiota in broilers. The optimal addition rate of CCHM was 5 mL/L.

Bacillus subtilis fmbj ameliorates lipopolysaccharide-induced intestinal dysfunction in broilers by enhancing the SIRT1/PGC1α pathway

This study aimed to explore the impact of dietary Bacillus subtilis fmbj (BS) supplementation on acute intestinal dysfunction induced by lipopolysaccharide (LPS) in broilers. One hundred and eighty 1-day-old male Arbor Acres broilers were randomly divided into three treatment groups, each comprising ten replicates of 6 birds. On d 20, LPS-challenged (LPS group and LPS-BS group) and LPS-unchallenged (CON group) broilers received intraperitoneal injections of 1 mg/kg body weight LPS solution and an equivalent volume of sterile saline, respectively. Compared to the CON group, LPS disrupted (P < 0.05) the morphology of the small intestine (jejunum or ileum), exacerbated (P < 0.05) serum, small intestinal, and small intestinal mitochondrial antioxidant capacity, induced (P < 0.05) small intestinal oxidative damage, and altered (P < 0.05) the expression of genes and proteins related to antioxidants, cell adhesion, and mitochondrial function in the jejunum. The LPS-BS group exhibited a tendency towards improvement in small intestinal morphology, serum, small intestinal, and small intestinal mitochondrial antioxidant capacity, small intestinal oxidative damage, and the expression of genes and proteins related to antioxidants, cell adhesion, and mitochondrial function in the jejunum when compared to the LPS group. In conclusion, BS supplementation may confer protection against LPS-induced acute intestinal dysfunction in broilers by enhancing the activation of SIRT1/PGC1α, suggesting its potential as a valuable additive for the poultry industry.

Effects of Crude Extract of Glycyrrhiza Radix and Atractylodes macrocephala on Immune and Antioxidant Capacity of SPF White Leghorn Chickens in an Oxidative Stress Model

The natural edible characteristics of Chinese herbs have led more and more people to study them as an alternative product to antibiotics. In this study, crude extracts of Glycyrrhiza radix and Atractylodes macrocephala (abbreviated as GRAM) with glycyrrhizic acid content not less than 0.2 mg/g were selected to evaluate the effects of GRAM on the immune and antioxidant capacity of model animals. Thirty 21-day-old male Leghorn chickens were weighed and randomly assigned to one of three groups of ten animals each. The treatments comprised a control group (CON), in which saline was injected at day 31, day 33, and day 35, an LPS-treated group (LPS), in which LPS (0.5 mg/kg of BW) was injected at day 31, day 33, and day 35, and finally a GRAM and LPS-treated group, (G-L) in which a GRAM-treated diet (at GRAM 2 g/kg) was fed from day 21 to day 35 with LPS injection (0.5 mg/kg of BW) at day 31, day 33, and day 35. The results of diarrhea grade and serum antioxidant measurement showed that the LPS group had obvious diarrhea symptoms, serum ROS and MDA were significantly increased, and T-AOC was significantly decreased. The oxidative stress model of LPS was successfully established. The results of immune and antioxidant indexes showed that feeding GRAM significantly decreased levels of the pro-inflammatory factors TNF-α, IL-1β, and IL-6 (p < 0.05) and significantly increased levels of the anti-inflammatory factors IL-4 and IL-10 and levels of the antioxidant enzymes GSH-Px and CAT (p < 0.05). GRAM resisted the influence of LPS on ileum morphology, liver, and immune organs and maintained normal index values for ileum morphology, liver, and immune organs. In summary, this study confirmed the antidiarrheal effect of GRAM, which improved the immune and antioxidant capacity of model animals by regulating inflammatory cytokine levels and antioxidant enzyme activity in poultry.

Mechanisms of lipopolysaccharide protection in tumor drug-induced macrophage damage

Malignant tumors contribute significantly to human mortality. Chemotherapy is a commonly used treatment for tumors. However, due to the low selectivity of chemotherapeutic drugs, immune cells can be damaged during antitumor treatment, resulting in toxicity. Lipopolysaccharide (LPS) can stimulate immune cells to respond to foreign substances. Here, we found that 10 ng/mL LPS could induce tolerance to antitumor drugs in macrophages without altering the effect of the drugs on tumor cells. Differentially expressed genes (DEGs) were identified between cells before and after LPS administration using transcriptome sequencing and found to be mainly associated with ATP-binding cassette (ABC)-resistant transporters and glutathione S-transferase (GST). LPS was shown by qRT-PCR and western blotting to promote the expression of ABCC1, GSTT1, and GSTP1 by 38.3 %, 194.8 %, and 27.0 %. Furthermore, three inhibitors (inhibitors of GST, glutathione synthesis, and ABCC1) were used for further investigation, showing that these inhibitors reduced macrophage survival rates by 44.0 %, 52.3 %, and 43.3 %, while the intracellular adriamycin content increased by 28.9 %, 42.9 %, and 51.3 %, respectively. These findings suggest that the protective mechanism of LPS on macrophages is associated with increased GST activity, the consumption of glutathione, and increased expression of ABCC1 protein. Therefore, LPS has a potential role in enhancing immunity.

Palygorskite improves growth performance and prevents liver damage in avian pathogenic Escherichia coli-challenged broiler chickens at an early age

Avian pathogenic Escherichia coli (APEC) is a major bacterial infection that causes economic losses in the global poultry industry. Palygorskite (PAL) has been shown to enhance growth performance while improving antioxidative and anti-inflammatory properties of broilers. This study evaluated the protective effects of PAL on growth performance and liver function in broilers subjected to APEC challenge. A total of 320 one-day-old male Arbor Acres chicks were divided into 4 groups with 8 replicates of 10 birds each, based on a 2 × 2 factorial arrangement (basal diet or 5 g/kg PAL-supplemented diet) and inoculation (bacterial culture medium or APEC). PAL increased body weight gain (BWG) prior to APEC challenge (P < 0.05). However, APEC caused losses in BWG, feed intake (FI), and feed efficiency, along with increased relative hepatic weight, hepatic pathology scores, and hepatic-cell apoptosis rate (P < 0.05). Compared to normal birds, APEC increased interleukin (IL)-1β, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), and nitric oxide (NO) levels, as well as lysozyme (LZM) and myeloperoxidase (MPO) activities, while decreasing total antioxidant capacity (T-AOC) and IL-10 levels, and total superoxide dismutase (T-SOD) and catalase (CAT) activities in both serum and liver, APEC also raised alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, but reduced total protein (TP), albumin (ALB), immunoglobulin (Ig) A, IgG, and IgM levels in serum (P < 0.05). Moreover, APEC increased hepatic mRNA level of IL-1β, IFN-γ, TNF-α, nuclear factor kappa B, and inducible nitric oxide synthase (iNOS), while inhibited mRNA level of IL-10 (P < 0.05). In contrast, PAL increased BWG and FI, and alleviated hepatic-cell apoptosis rate during the challenge period (P < 0.05). Incorporation of PAL reduced triglyceride and NO contents, ALT, and AST activities, while increasing TP, ALB, IL-10, IgG, and IgM levels in serum, enhancing serum T-SOD and CAT activities, elevating hepatic T-AOC and CAT activities, inhibiting hepatic MDA accumulation, and reducing IL-1β levels and LZM activity in both liver and serum (P < 0.05). An interactive effect was found for hepatic TNF-α and iNOS mRNA expression, in which PAL inhibited their mRNA expression in APEC-challenged birds (P < 0.05). Overall, PAL addition partially mitigated the negative impact of the APEC challenge on the growth performance and liver function of broiler chicks at an early age.

Effects of ferulic acid on growth performance and intestinal oxidation indexes of Jilin white geese under lipopolysaccharide-induced oxidative stress

In geese breeding, due to the frequent influence of drugs and environmental and other factors, geese are extremely prone to oxidative stress, which adversely affects growth and development, geese meat quality, down production, and severely affects the development of the geese industry. Ferulic acid from plant extracts can be used as a feed additive, which is safe and non-toxic, and it can exert certain therapeutic effects on oxidative stress in geese. This experiment investigated the effect of ferulic acid on the growth performance, organs indices, and intestinal oxidative indices of Jilin white geese under lipopolysaccharide-induced oxidative stress. Geese were randomly divided into six groups: C (blank control), L (lipopolysaccharide control), F1 (60 mg/kg ferulic acid), F2 (120 mg/kg ferulic acid), F3 (180 mg/kg ferulic acid), and F4 (240 mg/kg ferulic acid). Groups L and F1-F4 were injected intraperitoneally with 0.5 mg/kg lipopolysaccharide and group C with an equivalent volume of normal saline on days 14,17 and 20, and 10 animals from each group were randomly selected for slaughter on day 21. The results showed that: 1) On day 14, the final body weight and average daily feed intake were significantly higher in group F3 than in group L, and on day 21, the final body weight was significantly higher in group F3 than in group L. 2) The thymus index was significantly higher in group F4 than in group L. 4) In the duodenum, MDA activity was reduced in group C compared with that in group L. 5) In the jejunum and ileum, MDA was significantly lower in group F3 than in group L. These results show that the addition of 180 mg/kg of ferulic acid to the diet can promote the growth of geese and alleviate the damage caused by oxidative stress in all intestinal segments.

Integrated multi-omics reveals the beneficial role of chlorogenic acid in improving the growth performance and immune function of immunologically stressed broilers

Intensive production can cause immunological stress in commercial broilers. Chlorogenic acid (CGA) regulates the intestinal microbiota, barrier function, and immune function in chickens. As complex interrelations regulate the dynamic interplay between gut microbiota, the host, and diverse health outcomes, the aim of this study was to elucidate the immunoregulatory mechanisms of CGA using multi-omics approaches. A total of 240 one-day-old male broilers were assigned to a 2 × 2 factorial design with 2 CGA levels (0 or 500 mg/kg) either with or without dexamethasone (DEX) injection for a 21-day experimental period. Therefore, there were 4 dietary treatments: control, DEX, CGA, and DEX + CGA, with 6 replicates per treatment. CGA supplementation improved (P < 0.05) growth performance, jejunal morphology, jejunal barrier function, and immune function in DEX-treated broilers. Moreover, in DEX + CGA-treated broilers, the increase in gut microbiome diversity (P < 0.05) was consistent with a change in taxonomic composition, especially in the Clostridiales vadin BB60_group. Additionally, the levels of short-chain fatty acids increased remarkably (P < 0.01) after CGA supplementation. This was consistent with the Kyoto Encyclopedia of Genes and Genomes analysis results that the "pyruvate fermentation to butanoate" pathway was more enriched (P < 0.01) in the DEX + CGA group than in the DEX group. Proteomics revealed that CGA treatment increased the expression of several health-promoting proteins, thymosin beta (TMSB4X) and legumain (LGMN), which were verified by multiple reaction monitoring. Metabolomics revealed that CGA treatment increased the expression of health-promoting metabolites (2,4-dihydroxy benzoic acid and homogentisic acid). Proteomic and metabolic analyses showed that CGA treatment regulated the peroxisome proliferator-activated receptor (PPAR) and mitogen-activated protein kinase (MAPK) pathways. Western blotting results support these findings. Pearson's correlation analyses showed correlations (P < 0.01) between altered immune function, jejunal barrier function, different microbiota, proteins, and metabolites parameters. Overall, our data indicate that CGA treatment increased growth performance and improved the immunological functions of DEX-treated broilers by regulating gut microbiota and the PPAR and MAPK pathways. The results offer novel insights into a CGA-mediated improvement in immune function and intestinal health.

Chicken embryo thermal manipulation alleviates postnatal heat stress-induced jejunal inflammation by inhibiting Transient Receptor Potential V4

Intestinal inflammation induced by heat stress is an important factor restricting the healthy growth of broilers. The aim of this study was to evaluate the effect of chicken embryo thermal manipulation (39.5 ℃ and 65 % RH for 3 h daily during 16-18 th embryonic age) on intestinal inflammation in broilers under postnatal heat stress and to investigate whether transient receptor potential V4 (TRPV4) plays a role in this process. Our results suggest that broilers with embryo thermal manipulation experience could delay the rising of rectal temperature during postnatal heat stress (P < 0.05), and had better production performance (P < 0.05), intestinal morphological parameters (P < 0.05) and higher expression of tight junction related genes (P < 0.05). The increased serum lipopolysaccharide (LPS) content, activation of nuclear factor-kappa B (NF-κB) signaling pathway and the increased expression of pro-inflammatory cytokines interleukin (IL)-1β, IL-6 and tumor necrosis factor alpha (TNF-α) in jejunum during postnatal heat stress were alleviated by embryo thermal manipulation (P < 0.05). Postnatal heat stress induced an increase in mRNA and protein expression of TRPV4 in jejunum (P < 0.05), but had no effect on broilers which experienced embryo thermal manipulation (P > 0.05). Inhibition of TRPV4 reduced LPS-induced Ca²⁺ influx and restrained the activation of NF-κB signaling pathway and the expression of downstream pro-inflammatory cytokines (P < 0.05). The expression of DNA methyltransferase (DNMT) in the jejunum of broilers exposed to postnatal heat stress was increased by embryo thermal manipulation (P < 0.05). The DNA methylation level of TRPV4 promoter region was detected, and the results showed that embryo thermal manipulation increased the DNA methylation level of TRPV4 promoter region (P < 0.05). In conclusion, Chicken embryo thermal manipulation can alleviate jejunal inflammation in broilers under postnatal heat stress. This may be due to the decreased circulating LPS or the increased DNA methylation level in the promoter region of TRPV4, which inhibits TRPV4 expression, thereby reducing Ca²⁺ influx, and finally alleviating inflammation by affecting NF-κB signaling pathway. The work is an attempt to understand the mechanism involved in alleviation of adverse effects of heat stress during postnatal life through prenatal thermal manipulation and to reveal the important role of epigenetics.

Effects of supplementation of Bacillus amyloliquefaciens on performance, systemic immunity, and intestinal microbiota of weaned pigs experimentally infected with a pathogenic enterotoxigenic E. coli F18

The objective of this study was to investigate the effects of dietary supplementation of Bacillus (B.) amyloliquefaciens on growth performance, diarrhea, systemic immunity, and intestinal microbiota of weaned pigs experimentally infected with F18 enterotoxigenic Escherichia coli (ETEC). A total of 50 weaned pigs (7.41 ± 1.35 kg BW) were individually housed and randomly allotted to one of the following five treatments: sham control (CON-), sham B. amyloliquefaciens (BAM-), challenged control (CON+), challenged B. amyloliquefaciens (BAM+), and challenged carbadox (AGP+). The experiment lasted 28 days, with 7 days of adaptation and 21 days after the first ETEC inoculation. ETEC challenge reduced (P &lt; 0.05) average daily gain (ADG) of pigs. Compared with CON+, AGP+ enhanced (P &lt; 0.05) ADG, while B. amyloliquefaciens supplementation tended (P &lt; 0.10) to increase ADG in pigs from days 0 to 21 post-inoculation (PI). The ETEC challenge increased (P &lt; 0.05) white blood cell (WBC) count on days 7 and 21 PI, while BAM+ pigs tended (P &lt; 0.10) to have low WBC on day 7 PI and had lower (P &lt; 0.05) WBC on day 21 PI compared with CON+. In comparison to AGP+ fecal microbiota, BAM+ had a lower (P &lt; 0.05) relative abundance of Lachnospiraceae on day 0 and Clostridiaceae on day 21 PI, but a higher (P &lt; 0.05) relative abundance of Enterobacyeriaceae on day 0. In ileal digesta, the Shannon index was higher (P &lt; 0.05) in BAM+ than in AGP+. Bray-Curtis PCoA displayed a difference in bacterial community composition in ileal digesta collected from sham pigs vs. ETEC-infected pigs on day 21 PI. Pigs in BAM+ had a greater (P &lt; 0.05) relative abundance of Firmicutes, but a lower (P &lt; 0.05) relative abundance of Actinomycetota and Bacteroidota in ileal digesta than pigs in AGP+. Ileal digesta from AGP+ had a greater (P &lt; 0.05) abundance of Clostridium sensu stricto 1 but lower (P &lt; 0.05) Bifidobacterium than pigs in BAM+. In conclusion, supplementation of B. amyloliquefaciens tended to increase ADG and had limited effects on the diarrhea of ETEC-infected pigs. However, pigs fed with B. amyloliquefaciens exhibit milder systemic inflammation than controls. B. amyloliquefaciens differently modified the intestinal microbiota of weaned pigs compared with carbadox.

Effects of dietary chlorogenic acid on intestinal barrier function and the inflammatory response in broilers during lipopolysaccharide-induced immune stress

Immune stress exerts detrimental effects on growth performance and intestinal barrier function during intensive animal production with ensuing serious economic consequences. Chlorogenic acid (CGA) is used widely as a feed additive to improve the growth performance and intestinal health of poultry. However, the effects of dietary CGA supplementation on amelioration of the intestinal barrier impairment caused by immune stress in broilers are unknown. This study investigated the effects of CGA on growth performance, intestinal barrier function, and the inflammatory response in lipopolysaccharide (LPS) mediated immune-stressed broilers. Three hundred and twelve 1-day-old male Arbor Acres broilers were divided randomly into 4 groups with 6 replicates of thirteen broilers. The treatments included: i) saline group: broilers injected with saline and fed with basal diet; ii) LPS group: broilers injected with LPS and fed with basal diet; iii) CGA group: broilers injected with saline and feed supplemented with CGA; and iv) LPS+CGA group: broilers injected with LPS and feed supplemented with CGA. Animals in the LPS and LPS+CGA groups were injected intraperitoneally with an LPS solution prepared with saline from 14 d of age for 7 consecutive days, whereas broilers in the other groups were injected only with saline. LPS induced a decrease in feed intake of broilers during the stress period, but CGA effectively alleviated this decrease. Moreover, CGA inhibited the reduction of villus height and improved the ratio of villus height to crypt depth in the duodenum of broilers 24 and 72 h after LPS injection. In addition, dietary CGA supplementation significantly restored the expression of cation-selective and channel-forming Claudin2 protein 2 h after LPS injection in the ileum. LPS enhanced the expression of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the small intestine, but this enhancement was blocked by CGA supplementation. The expression of interleukin-10 (IL-10) increased with LPS injection and CGA promoted the production of IL-10. CGA addition downregulated the expression of intestinal interleukin-6 (IL-6) of broilers under normal rearing conditions. However, CGA supplementation upregulated the expression of IL-6 of broilers 72 h after LPS injection. The data demonstrate that dietary supplementation with CGA alleviates intestinal barrier damage and intestinal inflammation induced by LPS injection during immune stress thereby improving growth performance of broilers.

Bacterial lipopolysaccharide with different administration routes affects intestinal mucosal morphological, immunological, and microbial barrier functions in goslings

The current study was conducted to evaluate the effects of different administration routes of bacterial lipopolysaccharide (LPS) on intestinal mucosal morphological, immunological, and microbial barrier functions in goslings. First, we compared intestinal villi morphology of goslings under intraperitoneal or oral LPS treatment through hematoxylin and eosin staining. Then, we determined the signatures of the microbiome in the ileum mucosa of goslings subjected to oral LPS treatment at 0, 2, 4, and 8 mg/kg BW by 16S sequencing, and analyzed the changes in intestinal barrier functions and permeability, levels of LPS in the ileum mucosa, plasma, and liver tissue, and the induced inflammatory response of Toll-like receptor 4 (TLR4). As a result, intraperitoneal LPS injection resulted in a thicker intestinal wall in the ileum within a short time, whereas villus height was less affected; in contrast, oral LPS treatment exerted a stronger influence on villus height but not on intestinal wall thickness. We also found that oral LPS treatment affected the structure of the intestinal microbiome, reflected by changes in the clustering of intestinal microbiota. The average abundance of Muribaculaceae showed an increasing trend with increasing LPS levels, and that of the genus Bacteroides decreased, compared with the control group. In addition, oral LPS treatment with 8 mg/kg BW affected the intestinal epithelial morphology, damage the mucosal immune barrier, downregulated the expression of tight junction proteins, increased circulating D-lactate levels, and stimulated the secretion of various inflammatory mediators and activation of the TLR4/MyD88/NFκB pathway. This study presented the injuries of intestinal mucosal barrier function induced by LPS challenges in goslings and provided a scientific model for searching the novel strategies to attenuate the immunological stress and gut injury caused by LPS.

Dietary methionine restriction alleviates oxidative stress and inflammatory responses in lipopolysaccharide-challenged broilers at early age

In this study, we investigated the effect of dietary methionine restriction (MR) on the antioxidant function and inflammatory responses in lipopolysaccharide (LPS)-challenged broilers reared at high stocking density. A total of 504 one-day-old male Arbor Acre broiler chickens were randomly divided into four treatments: 1) CON group, broilers fed a basal diet; 2) LPS group, LPS-challenged broilers fed a basal diet; 3) MR1 group, LPS-challenged broilers fed a methionine-restricted diet (0.3% methionine); and 4) MR2 group, LPS-challenged broilers fed a methionine-restricted diet (0.4% methionine). LPS-challenged broilers were intraperitoneally injected with 1 mg/kg body weight (BW) of LPS at 17, 19, and 21 days of age, whereas the CON group was injected with sterile saline. The results showed that: LPS significantly increased the liver histopathological score (p < 0.05); LPS significantly decreased the serum total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activity at 3 h after injection (p < 0.05); the LPS group had a higher content of Interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF)-α, but a lower content of IL-10 than the CON group in serum (p < 0.05). Compared with the LPS group, the MR1 diet increased catalase (CAT), SOD, and T-AOC, and the MR2 diet increased SOD and T-AOC at 3 h after injection in serum (p < 0.05). Only MR2 group displayed a significantly decreased liver histopathological score (p < 0.05) at 3 h, while MR1 and MR2 groups did so at 8 h. Both MR diets significantly decreased serum LPS, CORT, IL-1β, IL-6, and TNF-α contents, but increased IL-10 content (p < 0.05). Moreover, the MR1 group displayed significantly increased expression of nuclear factor erythroid 2-related factor 2 (Nrf2), CAT, and GSH-Px at 3 h; the MR2 group had a higher expression of Kelch-like ECH-associated protein 1 (Keap1), SOD, and GSH-Px at 8 h (p < 0.05). In summary, MR can improve antioxidant capacity, immunological stress, and liver health in LPS-challenged broilers. The MR1 and MR2 groups experienced similar effects on relieving stress; however, MR1 alleviated oxidative stress more rapidly. It is suggested that precise regulation of methionine levels in poultry with stress may improve the immunity of broilers, reduce feed production costs, and increase production efficiency in the poultry industry.

Probiotics as a Friendly Antibiotic Alternative: Assessment of Their Effects on the Health and Productive Performance of Poultry

Antibiotics have been used to maintain the overall health of poultry by increasing production efficiency, promoting growth, and improving intestinal function for more than 50 years. However, they have a number of side effects, such as antibiotic resistance, gut dysbiosis, destruction of beneficial bacteria, and the potential to spread diseases to humans. In order to address the aforementioned issues, a lot of effort is put into the development of antibiotic alternatives. One of them is the use of probiotics that can be added to the feed in order to increase poultry performance and avoid the aforementioned problems. Probiotics are live microorganisms consumed as feed additives or supplements. They function in the poultry gastrointestinal tract to benefit the host. Probiotics improve growth performance, bone health, meat and eggshell quality. The addition of probiotics to the diet also positively affects the immune response, intestinal microflora, and disease resistance. Careful selection of probiotic strains is of utmost importance. This review focuses on the significance of probiotics as a potential antibiotic-free alternative and the way in which they can be used as supplements in poultry feed for boosting production and safeguarding health.

Serum metabolomics reveal pathways associated with protective effect of ginsenoside Rg3 on immune stress

Our previous study has demonstrated that administration of ginsenoside Rg3 ameliorates immune stress by inhibiting inflammatory responses, reducing oxidative damage and upregulating mRNA expression of mTOR, SOD-1, and HO-1. However, the specific mechanism in relation to the protective effect of ginsenoside Rg3 on stressed broilers especially the metabolites alteration remains obscure. The present study aimed to investigate the underlined mechanism in relation to the pathogenesis and protective effect of ginsenoside Rg3 on stressed broilers using liquid chromatograph-mass spectrometry profiling. Eighteen broiler chicks were randomly allocated to 3 treatments: Control, Model and Rg3. Chickens in Rg3 group received intraperitoneally administered 1 mg/kg Rg3 2 h before LPS challenge. Then the broilers were intraperitoneally injection of 250 µg/kg LPS at the age of 12, 14, 33, and 35 d to induce immune stress. Control group was injected with an equivalent amount of sterile saline. At the end of the experiment, the serum was obtained for metabolomics analysis. The changes in serum metabolic profiles were investigated with the application of metabolomics approach. Distinct changes in metabolite patterns in serum were observed by orthogonal partial least square-discriminate analysis. In total, 35 metabolites were identified, among which 17 differential metabolites were found between Control and Model group, and 18 differential metabolites were identified between Model and Rg3 group. Metabolic pathway analysis revealed potential serum metabolites involved in oxidative stress and inflammation, degradation of lipid and protein in broiler chicks with immune stress. In addition, the protective effect of Rg3 on the stressed chicks may be largely mediated by BCAA metabolism, apoptosis and mTOR signaling pathway. These results suggested the potential biomarkers involved in pathogenesis and prevention of stress induced by Escherichia coli lipopolysaccharide.

Effects of betaine on growth performance, intestinal health, and immune response of goslings challenged with lipopolysaccharide

The objective of this experiment was to investigate the effects of betaine on growth performance, serum parameters, intestinal health, and immune performance of goslings in response to lipopolysaccharide (LPS) challenge. A total of 168 healthy male 15-day-old Jiangnan White Goslings were randomly divided into 4 groups, with 6 replicates per treatment and seven goslings per replicate. A 2 × 2 factorial arrangement included 2 factors, that is, LPS challenge (injection of LPS or physiological saline) and betaine (added 0 or 0.06% betaine in diet). The results indicated that LPS challenge significantly reduced the average daily feed intake (ADFI), average daily gain (ADG), and body weight (BW) at 21 D of the goslings, while dietary betaine supplementation tended to increase the ADFI during the LPS stress period (P = 0.08) and BW at 21 D of the goslings (P = 0.09). The LPS-challenged goslings showed higher pro-inflammatory cytokines (interleukin-1 [IL-1β], interleukin-6 [IL-6], tumor necrosis factor-α (TNF-α), and Interferon-gamma [IFN-γ]) and lower anti-inflammatory cytokine (Interleukin-10 [IL-10]) (P < 0.05) at 21 D of age. Dietary betaine supplementation alleviated LPS-induced increase in pro-inflammatory cytokines. The LPS challenge significantly decreased duodenal and jejunal villus height (VH) and villus height and crypt depth ratio (VCR), while the addition of betaine significantly increased duodenal VH and VCR (P < 0.05). On the other hand, addition of betaine significantly alleviated decline of enzyme activity on lipase, amylase, trypsin, and chymotrypsin in the intestinal of goslings. The LPS challenge significantly increased the content of serum D-lactic acid (D-LA) and the activity of diamine oxidase (DAO) at 21 D of the goslings. The LPS challenge and betaine addition significantly increased the mRNA expression of Occcludin (OCLN) in jejunal mucosa at 28 D of the goslings (P < 0.05). In conclusion, our research demonstrated that betaine can alleviate the decline of growth performance and immune performance in goslings caused by LPS. The results also indicate betaine possesses anti-inflammation properties and improves intestinal barrier functions. We recommend that 0.06% betaine be added into the diet to improve the intestinal health and immune performance of goslings.

Dietary Eugenol Nanoemulsion Potentiated Performance of Broiler Chickens: Orchestration of Digestive Enzymes, Intestinal Barrier Functions and Cytokines Related Gene Expression With a Consequence of Attenuating the Severity of E. coli O78 Infection

Recently, the use of essential oils (EOs) or their bioactive compounds encapsulated by nanoparticles as alternative supplements for in-feed antimicrobials is gaining attention, especially in organic poultry production. Focusing on eugenol, its incorporation into the nanoformulation is a novel strategy to improve its stability and bioavailability and thus augment its growth-boosting and antimicrobial activities. Therefore, we explored eugenol nanoemulsion activities in modulating growth, digestive and gut barrier functions, immunity, cecal microbiota, and broilers response to avian pathogenic E. coli challenge (APEC) O78. A total of 1,000 one-day-old broiler chicks were allocated into five groups; negative control (NC, fed basal diet), positive control (PC), and 100, 250, and 400 mg/kg eugenol nanoemulsion supplemented groups. All groups except NC were challenged with APEC O78 at 14 days of age. The results showed that birds fed eugenol nanoemulsion displayed higher BWG, FI, and survivability and most improved FCR over the whole rearing period. Birds fed 400 mg/kg of eugenol nanoemulsion sustained a higher growth rate (24% vs. PC) after infection. Likely, the expression of digestive enzymes' genes (AMY2A, CCK, CELA1, and PNLIP) was more prominently upregulated and unaffected by APEC O78 challenge in the group fed eugenol nanoemulsion at the level of 400 mg/kg. Enhanced gut barrier integrity was sustained post-challenge in the group supplemented with higher levels of eugenol nanoemulsion as evidenced by the overexpression of cathelicidins-2, β-defensin-1, MUC-2, JAM-2, occludin, CLDN-1, and FABP-2 genes. A distinct modulatory effect of dietary eugenol nanoemulsion was observed on cytokine genes (IL-1β, TNF-α, IL-6, IL-8, and IL-10) expression with a prominent reduction in the excessive inflammatory reactions post-challenge. Supplementing eugenol nanoemulsion increased the relative cecal abundance of Lactobacillus species and reduced Enterobacteriaceae and Bacteriods counts. Notably, a prominent reduction in APEC O78 loads with downregulation of papC, iroN, iutA, and iss virulence genes and detrimental modifications in E. coli morphological features were noticed in the 400 mg/kg eugenol nanoemulsion group at the 3rd-week post-challenge. Collectively, we recommend the use of eugenol nanoemulsion as a prospective targeted delivery approach for achieving maximum broilers growth and protection against APEC O78 infection.

Effects of Solid-State Fermented Wheat Bran on Growth Performance, Immune Function, Intestinal Morphology and Microflora in Lipopolysaccharide-Challenged Broiler Chickens

The study evaluated the effects of dry and wet solid-state fermented wheat bran (FWB) on growth performance, immune function, intestinal morphology and microflora in lipopolysaccharide (LPS)-challenged broiler chickens. The experiment was designed as a 2 × 3 factorial arrangement. A total of 252 one-day-old Arbor Acres male broiler chickens were randomly allocated to 1 of 6 treatments: basal diet + sterile saline (negative control, NC), basal diet + LPS (positive control, PC), 7% dry FWB + sterile saline (FWB-I), 7% dry FWB + LPS (FWB-II), 7% wet FWB + sterile saline (FWB-III) and 7% wet FWB + LPS (FWB-IV), with containing 6 replicate cages/treatment and 7 broiler chickens/cage, and the experimental period lasted for 42 days. Broilers were intraperitoneally injected with either 0.5 mg LPS or sterile saline solution per kg body weight at 16, 18 and 20 d of age. Growth performance, serum immunological parameters and indicators related to intestinal health were analyzed on days 21 and 42. Compared with NC, dry and wet FWB significantly increased (p < 0.05) average daily feed intake of days 21 to 42, and increased (p < 0.05) the villus height and villus height to crypt depth ratio of ileum on day 21, decreased (p = 0.101) the jejunum crypt depth and decreased (p < 0.05) the Lactobacillus and Bifidobacterium counts of the cecum digesta on day 42. Compared with NC, FWB-II and FWB-IV significantly increased (p < 0.05) the levels of serum total protein and globulin on day 21; compared with the basal diet groups, dry and wet FWB groups significantly increased (p < 0.05) glucose levels on day 21, and wet FWB significantly decreased (p < 0.05) alanine aminotransferase levels on day 42. Compared with PC and FWB-II, FWB-IV significantly increased (p < 0.05) the level of serum immunoglobulin G on day 21. Compared with PC and FWB-II, FWB-IV significantly decreased (p < 0.05) the levels of serum pro-inflammatory cytokines interleukin (IL)-6, IL-8, IL-1β and acute C reactive protein (CRP) on day 21; compared with FWB-III, FWB-IV significantly decreased (p < 0.05) the levels of IL-6, IL-8, CRP and tumor necrosis factor alpha on day 42, but the levels of IL-4 and IL-10 were significantly increased (p < 0.05) on days 21 and 42. These results indicated that supplementing 7% dry or wet FWB can improve growth performance and serum immune functions of broilers, which effectively alleviate the LPS-challenged damage, and wet FWB had a better effect than dry FWB.

Effect of Immune Stress on Growth Performance and Immune Functions of Livestock: Mechanisms and Prevention

Simple Summary

Immune stress is an important stressor in domestic animals that leads to decreased feed intake, slow growth, and reduced disease resistance of pigs and poultry. Especially in high-density animal feeding conditions, the risk factor of immune stress is extremely high, as they are easily harmed by pathogens, and frequent vaccinations are required to enhance the immunity function of the animals. This review mainly describes the causes, mechanisms of immune stress and its prevention and treatment measures. This provides a theoretical basis for further research and development of safe and efficient prevention and control measures for immune stress in animals.

Abstract

Immune stress markedly affects the immune function and growth performance of livestock, including poultry, resulting in financial loss to farmers. It can lead to decreased feed intake, reduced growth, and intestinal disorders. Studies have shown that pathogen-induced immune stress is mostly related to TLR4-related inflammatory signal pathway activation, excessive inflammatory cytokine release, oxidative stress, hormonal disorders, cell apoptosis, and intestinal microbial disorders. This paper reviews the occurrence of immune stress in livestock, its impact on immune function and growth performance, and strategies for immune stress prevention.

Effects of Probiotics on the Growth Performance, Antioxidant Functions, Immune Responses, and Caecal Microbiota of Broilers Challenged by Lipopolysaccharide

We aimed to study the effects of dietary Bacillus coagulans (B. coagulans) and Lactobacillus plantarum (L. plantarum) on broilers challenged by Escherichia coli lipopolysaccharide (LPS). One-day-old Cobb 500 chicks (360) were divided randomly into three treatment groups for 47 days: no supplementation (control, CON), B. coagulans supplementation (BC), and L. plantarum supplementation (LA). Broilers were routinely fed for 42 days and intraperitoneally injected with 500 μg LPS per kg body weight at 43, 45, and 47 days of age, respectively. Samples were collected 3 h after the last injection. At 1-21 days of age, the ADG in the BC and LA groups was higher than that in the CON group, and the feed to gain ratio (F/G) in the BC group was significantly decreased (P < 0.05). Compared with that in CON birds, the ADG was increased and the F/G was decreased in the BC and LA birds at 22-42 and 1-42 days of age, respectively (P < 0.05). After LPS stimulation, the endotoxin (ET), diamine oxidase (DAO), and D-lactic acid (D-LA) levels in the BC group were lower than those in the CON group (P < 0.05). The IgY, IgA, and IgM contents in the BC group and the IgY and IgM contents in the LA group were higher than those in the CON group (P < 0.05). The pro-inflammatory factor and interferon-β (IFN-β) contents (P < 0.05) decreased, and the anti-inflammatory factor content in the serum (P < 0.05) increased in the BC and LA groups. Compared with the CON and LA treatments, the BC treatment increased the concentrations of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT), and decreased that of malondialdehyde (MDA) (P < 0.05). In contrast with the CON treatment, the BC and LA treatments increased the abundance of Ruminococcaceae and reduced that of Desulfovibrio (P < 0.05). Moreover, BC increased the abundance of beneficial bacteria. Overall, supplementation with B. coagulans and L. plantarum promoted the growth of broilers, improved their immunity and antioxidant capacity, and alleviated the LPS-stimulated inflammatory response by regulating the intestinal flora.

The influence of immune stress induced by Escherichia coli lipopolysaccharide on the pharmacokinetics of danofloxacin in broilers

This study aimed to determine whether the challenge from Escherichia coli (E. coli) lipopolysaccharide (LPS) affects the pharmacokinetics of danofloxacin in broilers. Twenty 1-day-old Arbor Acres (AA) broilers were equally and randomly divided into 2 groups. When the chickens were 23, 25, 27, and 29 days old, E. coli LPS (1 mL; 0.5 mg/kg body weight [BW]) and sterile saline (1 mL) were intraperitoneally injected into the two groups. After the last injection, danofloxacin was given to all chickens by gavage at the dose of 5 mg/kg BW. Then serum and plasma samples at each time point were collected through the wing vein. Danofloxacin concentrations in plasma were detected through the high-performance liquid chromatography (HPLC) method and subjected to noncompartmental analysis using Phoenix software. The levels of chicken interleukin-1β (IL-1β) and corticosterone (CORT) in serum were measured by the Enzyme-linked immunosorbent assay (ELISA) kit. In addition, after the collection of plasma or serum samples, 7 chickens (31 days of age) in each group were killed to calculate the organ indices. Compared with the control group, the challenge of LPS significantly decreased the parameters of AUC0-∞, Cmax, and t1/2λz and increased the parameters of Tmax and λz. Additionally, in the LPS group, the absorption time of danofloxacin was prolonged; however, the elimination was accelerated, which resulted in reduced internal exposure.

Bacillus amyloliquefaciens and Saccharomyces cerevisiae feed supplements improve growth performance and gut mucosal architecture with modulations on cecal microbiota in red-feathered native chickens

Objective

The aim of study was to investigate the effects of in-feed supplementation of Bacillus amyloliquefaciens (BA) and Saccharomyces cerevisiae (SC) on growth performance, gut integrity, and microbiota modulations in red-feathered native chickens (RFCs).

Methods

A total of 18,000 RFCs in a commercial farm were evenly assigned into two dietary treatments (control diet; 0.05% BA and 0.05% SC) by randomization and raised for 11 weeks in two separate houses. Fifty RFCs in each group were randomly selected and raised in the original house with the partition for performance evaluations at the age of 9 and 11 weeks. Six non-partitioned RFCs per group were randomly selected for analyses of intestinal architecture and 16S rRNA metagenomics.

Results

Feeding BA and SC increased the body weight and body weight gain, significantly at the age of 11 weeks (p<0.05). The villus height/crypt ratio in the small intestines and Firmicutes to Bacteroidetes ratio were also notably increased (p<0.05). The supplementation did not disturb the microbial community structure but promote the featured microbial shifts characterized by the significant increments of Bernesiella, Prevotellaceae_NK3B31_group, and Butyrucimonas, following remarkable decrements of Bacteroides, Rikenellaceae_RC9_gut_group, and Succinatimonas in RFCs with growth benefits. Besides, functional pathways of peptidoglycan biosynthesis, nucleotide excision repair, glycolysis/gluconeogenesis, and aminoacyl transfer ribonucleic acid (tRNA) biosynthesis were significantly promoted (p<0.05).

Conclusion

In-feed supplementation of BA and SC enhanced the growth performance, improved mucosal architectures in small intestines, and modulated the cecal microbiota and metabolic pathways in RFCs.

Maternal Supplementation with Artemisia annua L. Ameliorates Intestinal Inflammation via Inhibiting the TLR4/NF-κB and MAPK Pathways and Improves Oxidative Stability of Offspring

Artemisia annua L. (A. annua) contains artemisinin, which attracts attention on account of its anti-inflammatory and anti-oxidant effects. The increased intestinal inflammation, oxidative stress, and hypoimmunity commonly occur in the...

<i>Bacillus subtilis-</i>Fermented Products Ameliorate the Growth Performance, Alleviate Intestinal Inflammatory Gene Expression, and Modulate Cecal Microbiota Community in Broilers during the Starter Phase under Dextran Sulfate Sodium Challenge

The aim of this study was to evaluate the effects of B. subtilis-fermented products (BSFP) on growth performance, intestinal inflammatory gene expression, and cecal microbiota community in broilers challenged with dextran sulfate sodium (DSS) in a 14-day experiment. A total of 32, 1-day-old male broiler chickens (Ross 308), were randomly divided into four groups of eight birds per group and reared individually (n=8). The treatments consisted of a control diet without supplementation and DSS challenge, control diet plus 1.5% DSS, control diet plus 1 g/kg BSFP in combination with 1.5% DSS, and control diet plus 3 g/kg of BSFP in combination with 1.5% DSS. The results showed that BSFP supplementation (1 and 3 g/kg) partially improved body weight and average daily gain in broilers under DSS challenge. Relative to DSS treatment alone, BSFP supplementation dose-dependently increased the body weight of broilers at 7 days of age, with the average daily gain being at 1 to 7 days of age. BSFP supplementation (1 and 3 g/kg) alleviated intestinal inflammatory gene expression in broilers under DSS challenge. The richness and evenness of bacterial species in cecal digesta increased in a dose-dependent manner in the groups treated with BSFP (1 and 3 g/kg) in combination with DSS challenge, compared with the control group. Unweighted principal coordinate analysis indicated distinct clusters separating the group treated with 3 g/kg of BSFP in combination with DSS challenge from the other three groups. The abundance of short-chain fatty acid-producing bacteria (genus Ruminococcaceae_unclassified) increased and that of mucindegrading bacteria (genus Ruminococcus torques group) decreased in the cecal digesta of broilers fed 3 g/kg of BSFP, compared with the control group. In conclusion, BSFP supplementation dose-dependently improved growth performance, reduced gut inflammation, and regulated the cecal microbiota of broilers exposed to DSS challenge during the starter phase.

Molecular mechanisms of growth depression in broiler chickens (Gallus Gallus domesticus) mediated by immune stress: a hepatic proteome study

Background

Immunological stress decreases feed intake, suppresses growth and induces economic losses. However, the underlying molecular mechanism remains unclear. Label-free liquid chromatography and mass spectrometry (LC-MS) proteomics techniques were employed to investigate effects of immune stress on the hepatic proteome changes of Arbor Acres broilers (Gallus Gallus domesticus) challenged with Escherichia coli lipopolysaccharide (LPS).

Results

Proteomic analysis indicated that 111 proteins were differentially expressed in the liver of broiler chickens from the immune stress group. Of these, 28 proteins were down-regulated, and 83 proteins were up-regulated in the immune stress group. Enrichment analysis showed that immune stress upregulated the expression of hepatic proteins involved in defense function, amino acid catabolism, ion transport, wound healing, and hormone secretion. Furthermore, immune stress increased valine, leucine and isoleucine degradation pathways.

Conclusion

The data suggests that growth depression of broiler chickens induced by immune stress is triggered by hepatic proteome alterations, and provides a new insight into the mechanism by which immune challenge impairs poultry production.

Protective Effect of Lactobacillus plantarum P8 on Growth Performance, Intestinal Health, and Microbiota in Eimeria-Infected Broilers

Coccidiosis is one of the major parasitic diseases in the commercial broiler industry. Probiotics can protect poultry against Eimeria infection. However, the mechanisms are not fully known. Therefore, Lactobacillus plantarum P8 (P8) was used to investigate its anti-coccidial property and mechanism. Five hundred broilers were allocated to five treatments: control diet (NC), control diet + Eimeria infection (IC), control diet containing 1 × 10⁷ cfu/g P8 + Eimeria infection (P8L), control diet containing 1 × 10⁸ cfu/g P8 + Eimeria infection (P8H), and control diet + Eimeria infection + Diclazuril (DIC). At day 14, all treatments except NC were inoculated with sporulated oocysts. Results indicated that Eimeria infection increased the mortality and oocysts shedding, and declined the growth performance as well as the intestinal barrier in Eimeria-treated broilers. On the contrary, dietary supplementation of low level P8, high level P8 and DIC decreased the mortality and oocysts shedding, but improved the growth performance and intestinal barrier. The impaired intestinal morphology in the IC group was also improved by P8H and DIC treatments. Besides, the elevated oxidative stress and pro-inflammation in Eimeria-infected broilers were reduced by P8L, P8H, and DIC treatments. Metagenomic analysis indicated P8 altered the structure of the gut microbiota, and the alteration was more obvious at day 21 than day 42. Notably, IC also increased the abundances of Eimeriidae, Eimeria and Eimeria tenella at day 21, while P8L and DIC decreased the abundances. Correlation analysis revealed that bacteria in Eimeria-treated broilers positively correlated with the intestinal permeability, oxidative stress and inflammation, while bacteria in broilers receiving P8L and DIC negatively correlated with the aforementioned pathological indices. Functional prediction demonstrated that the metagenomes of Eimeria-infected broilers were involved in several diseases. But the metagenomes of P8L-treated broilers were involved in energy metabolism and replication repair. In conclusion, dietary P8 supplementation inhibited oocyst shedding and improved the growth performance as well as the intestinal health of broilers infected with Eimeria, which was closely related to the regulation of gut microbiota. Moreover, the effects of P8 may be more effective in the early infection of coccidia.

Bacillus amyloliquefaciens BLCC1-0238 Can Effectively Improve Laying Performance and Egg Quality Via Enhancing Immunity and Regulating Reproductive Hormones of Laying Hens

In this study, we sought to evaluate the effects of dietary Bacillus amyloliquefaciens (B. amyloliquefaciens) BLCC1-0238 supplementation on laying performance, egg quality, antioxidant enzyme activities, reproductive hormone, and immunity of laying hens. A total of 240 Hy-Line Brown laying hens (28 weeks old) were randomly divided into four groups, and three replicates per group (n = 20 per replicate). The control group was fed a standard basal diet, and the three treatment groups were provided the basal diet supplemented with either 0.01%, 0.03%, or 0.06% B. amyloliquefaciens BLCC1-0238 (2 × 10¹⁰ CFU/g), respectively. Hens were allowed 2 weeks to acclimate prior to initiation of the 8-week experiment. It was observed that dietary supplementation with 0.01% or 0.03% B. amyloliquefaciens BLCC1-0238 significantly increased egg production and egg mass. However, no significant differences in feed intake, egg weight, and feed conversion ratio among the four groups were observed. Different levels of B. amyloliquefaciens BLCC1-0238 supplementation also significantly increased egg shell strength and thickness. With respect to the levels of reproductive hormones in the hens, B. amyloliquefaciens BLCC1-0238 supplementation significantly reduced serum adrenal cortical hormone (ACTH) levels, while increasing estradiol (E2) and follicle-stimulating hormone (FSH) secretion in the treatment groups compared to the control group. Relative to the control group, supplementation with 0.03% and 0.06% B. amyloliquefaciens BLCC1-0238 was observed to significantly increase serum glutathione S-transferase (GST) concentration, and supplementation significantly reduced serum IL-1 and IL-6 levels, whereas IL-4 levels increased for all concentrations tested. In conclusion, supplementation of a basal chicken diet with B. amyloliquefaciens BLCC1-0238 can improve laying performance and egg quality through the reduction of stress responses, up-regulation of growth hormones, and supporting immunity in laying hens.

Research Note: Immunocompetent cells in blood and intestine after administration of Lacto-Immuno-Vital in drinking water of broiler chickens

The understanding of the synbiotics´ impact on the host is incomplete. To improve the knowledge, we study the effect of Lacto-Immuno-Vital synbiotic preparation in chickens on local and systemic immune response by evaluation of immunocompetent cells in the peripheral blood and jejunal mucosa. Hematological method was used for determination of white blood cell count, and flow cytometry for measurement the functions of phagocytes and subpopulation of lymphocytes (CD3, CD4, CD8, IgM, and IgA). Cell Qest programme (Germany) was used for analysing of data obtained from flow cytometer and GraphPad Prism version 4.0 for comparison by paired t test between control and experimental groups. The experiment was conducted in a commercial broiler chicken fattening farm, the birds were handled and sacrificed in a humane manner. A flock of 64,400 one-day-old Hybrid ROSS 308 chickens were included in the 42-d experiment. The chickens were randomly divided into 2 equal groups, experimental and control, and each group of chickens was housed in a different hall while maintaining the same conditions. The chickens in the experimental group (Lactovital) received 500 g of Lacto-Immuno-Vital (Hajduvet Kft., Hungary) in 1,000 L of drinking water. Lacto-Immuno-Vital was administered daily from the first day (D1) to D7 of the experiment. From D 7 to D 22 it was given in a pulsed manner (every third day) at a dose of 300 g in 1,000 L of drinking water. Control group received only the standard diet. For immune analyses 6 randomly chosen chickens from experimental and control group were taken from the halls. The sampling days were set at D 8 and D 22 of the experiment. Samples of peripheral blood were collected from vena subclavia. The chickens were euthanized and whole jejunum was taken during necropsy into Hanks ice solution (pH 7.2–7.3). Administration of Lacto-Immuno-Vital in drinking water of nonstressed broilers during fattening period in commercial production increased phagocytic activity and phagocytic index. The number of IgA+ and CD8+ cells in lamina propria of intestine was decreased in chickens fed diet supplemented with Lacto-Immuno-Vital in drinking water. We suggest that increased phagocytic activity and decreased number of immunocompetent cells in mucosa of intestine was caused by improved systemic and local immune system function.

Effects of Artemisia argyi flavonoids on growth performance and immune function in broilers challenged with lipopolysaccharide

Objective

This research aimed to study the effects of Artemisia argyi flavonoids (AAF) supplemented in diets on the growth performance and immune function of broiler chickens challenged with lipopolysaccharide (LPS).

Methods

A total of one hundred and ninety-two 1-d-old broiler chicks were assigned into 4 treatment groups, which were, respectively, fed a basal diet (control), fed a diet with 750 mg/kg AAF, fed a basal diet, and challenged with LPS, fed a diet with 750 mg/kg AAF, and challenged with LPS. Each treatment had six pens with 8 chicks per pen. On days 14, 16, 18, 20 (stress phase I) and 28, 30, 32, 34 (stress phase II), broilers were injected with LPS (500 μg/kg body weight) or an equivalent amount of saline.

Results

The results demonstrated that dietary AAF significantly improved the body weight (d 21) and alleviated the decrease of average daily gain in broilers challenged with LPS on d 21 and d 35 (p<0.05). Dietary AAF increased bursa fabricius index, and dramatically attenuated the elevation of spleen index caused by LPS on d 35 (p<0.05). Furthermore, serum interleukin-6 (IL-6) concentration decreased with AAF supplementation on d 21 (p<0.05). Diet treatment and LPS challenge exhibited a significant interaction for the concentration of IL-1β (d 21) and IL-6 (d 35) in serum (p<0.05). Additionally, AAF supplementation mitigated the increase of IL-1β, IL-6 in liver and spleen induced by LPS on d 21 and 35 (p<0.05). This study also showed that AAF supplementation significantly reduced the expression of IL-1β (d 21) and nuclear transcription factor kappa-B p65 (d 21 and 35) in liver (p<0.05), and dietary AAF and LPS treatment exhibited significant interaction for the gene expression of IL-6 (d 21), toll like receptor 4 (d 35) and myeloid differentiation factor 88 (d 35) in spleen (p<0.05).

Conclusion

In conclusion, AAF could be used as a potential natural immunomodulator to improve growth performance and alleviate immune stress in broilers challenged with LPS.

Dietary taurine supplementation attenuates lipopolysaccharide-induced inflammatory responses and oxidative stress of broiler chickens at an early age

This study was conducted to investigate the effect of taurine as a prophylactic treatment on antioxidant function and inflammatory responses of broilers challenged with lipopolysaccharide (LPS). A total of 256 one-day-old male Arbor Acres broiler chicks were randomly assigned to four treatments with eight replicates of eight birds (eight birds per cage). Four treatment groups were designated as follows: 1) in the CON group, broilers fed a basal diet; 2) in the LPS group, LPS-challenged broilers fed a basal diet; 3) in the LPS + T1 group, LPS-challenged broilers fed a basal diet supplemented with 5.0 g/kg taurine; and 4) in the LPS + T2 group, LPS-challenged broilers fed a basal diet supplemented with 7.5 g/kg taurine. The LPS-challenged broilers were intraperitoneally injected with 1 mg/kg body weight (BW) of LPS at 16, 18, and 20 d of age, whereas the CON group received an injection of sterile saline. The results showed that broilers injected with LPS exhibited decreased (P < 0.05) the average daily gain (ADG) and the 21-d BW (P < 0.05), while taurine supplementation alleviated the negative effects of LPS. Additionally, the LPS-induced increases (P < 0.05) in serum alanine transaminase and aspartate transaminase activities were reversed by taurine supplementation. The taurines could alleviate the hepatic oxidative stress, with the presence of lower content of malondialdehyde (P < 0.05), higher content of glutathione (P < 0.05), and an increased glutathione peroxidase (GSH-Px) activity (P < 0.05). The concentrations of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in the liver were measured by ELISA kits, and the result showed that dietary taurine supplementation prevented these cytokines increases in the liver of LPS-induced broilers. Taurine reduced the genes expression of IL-1β, TNF-α, IL-6, cyclooxygenase-2, and inducible nitric oxide synthase, whereas it boosted the expression levels of antioxidant-related genes (nuclear factor erythroid 2-related factor 2, heme oxygenase-1, glutamate-cysteine ligase catalytic subunit, and GSH-Px) in the liver of LPS-induced broilers. In conclusion, dietary taurine supplementation in broilers mitigated LPS-induced defects in ADG, oxidative stress, and inflammatory responses.

Bacillus subtilis-fermented products ameliorate the growth performance and alter cecal microbiota community in broilers under lipopolysaccharide challenge

In this study, the effects of Bacillus subtilis–fermented products on the growth performance and cecal microbiota of broilers were investigated in response to lipopolysaccharide (LPS) challenge. A total of 120 one-day-old male broiler chicks (Ross 308) were randomly assigned to 4 dietary treatments, with 5 replicate cages per treatment and 6 birds per cage. The dietary treatments comprised a basal diet as the control, basal diet plus 5 mg/kg of LPS, and basal diet plus 5 mg/kg of LPS in combination with 1 and 3 g/kg of B. subtilis–fermented products. The results indicated that B. subtilis–fermented product supplementation increased (linear, P < 0.05) the body weight of broilers relative to LPS treatment alone at 21 d of age. At 15 to 21 d and 1 to 21 d of age, B. subtilis–fermented product supplementation improved (linear, P < 0.05) the average daily gain in broilers compared with LPS challenge alone. The inflammation-associated gene expression was decreased (P < 0.05), and intestinal barrier–associated gene expression was increased (P < 0.05) in the small intestine of the group treated with 3 g/kg of B. subtilis–fermented products in combination with LPS challenge. In cecal microbiota analysis, the richness of bacterial species was lower (P < 0.05) in the groups treated with 1 and 3 g/kg of B. subtilis–fermented products in combination with LPS challenge than in the control group. Principal coordinates analysis indicated distinct clusters between the groups treated with LPS alone and B. subtilis–fermented products in combination with LPS challenge. The abundance of the genera Erysipelatoclostridium and Ruminococcaceae_unclassified in the cecal digesta decreased (P < 0.05) in broilers fed with B. subtilis–fermented products compared with the control group. The average abundance of the genera Bacteroides and Romboutsia in the cecal digesta was positively correlated with the body weight and average daily gain of broilers in response to LPS challenge. Furthermore, the average abundance of the genera Bacteroides and Romboutsia in the cecal digesta was positively correlated with the concentration of B. subtilis–fermented products under LPS challenge. These results demonstrate that B. subtilis–fermented products can improve the growth performance and modulate the gut microflora composition of broilers under immune stress.

Effects of dietary pyrroloquinoline quinone disodium supplementation on inflammatory responses, oxidative stress, and intestinal morphology in broiler chickens challenged with lipopolysaccharide

This study was conducted to investigate the effects of pyrroloquinoline quinone disodium (PQQ·Na2) on inflammatory responses, oxidative stress, and intestinal morphology of broiler chickens challenged with lipopolysaccharide (LPS). A 2 × 2 factorial arrangement in a complete randomized design experiment was used to study the effect of dietary PQQ·Na2 (0 or 1 mg/kg) on broiler chickens with or without a challenge with LPS. A total of two hundred eighty-eight 1-day-old Arbor Acre broiler chickens were randomly assigned to 4 treatments with 6 replicate cages of 12 birds per cage. All experimental broilers were injected intraperitoneally with 0.5 mg/kg body weight of either Escherichia coli LPS or sterile saline at 16, 18, and 20 d of age. Results showed that injecting LPS significantly increased the concentrations of interleukin-1beta (IL-1β) in serum of birds on day 20 and day 21. Meanwhile, LPS injection increased (P < 0.05) the relative mRNA expression of interleukin-6 (IL-6) in the duodenal mucosa of broilers on day 21. However, dietary supplementation with PQQ·Na2 decreased (P < 0.05) the concentration of IL-6 in serum of birds on day 20 and the levels of IL-1β, IL-6, and interleukin-10 (IL-10) in serum of broiler chickens on day 21. Besides, supplementation of PQQ·Na2 within diet decreased (P < 0.05) the mRNA expressions of IL-1β and IL-10 in the duodenal mucosa of birds on day 20. Relative to saline injection, the activity of glutathione peroxidase (GSH-Px) in serum and the activities of total superoxide dismutase (T-SOD) and catalase (CAT) in liver were found to be lower (P < 0.05) in broilers after LPS challenge on day 21. However, birds fed with PQQ·Na2 showed higher (P < 0.05) GSH-Px activity in serum and higher (P < 0.05) T-SOD activities in liver on day 21 and day 42. Pyrroloquinoline quinone disodium also significantly attenuated the LPS-induced decreases in villus height to crypt depth ratio in the duodenum of broilers. In conclusion, dietary PQQ·Na2 supplementation significantly exerted protective effects on inflammation damage and oxidant stress of broilers under LPS challenge by regulating the expression of inflammatory cytokines (IL-1β, IL-6, and IL-10) and activities of antioxidant enzymes (GSH-Px, T-SOD, and CAT). Moreover, dietary PQQ·Na2 supplementation significantly ameliorated the LPS-impaired intestinal morphology in broilers. Therefore, it has been considered that PQQ·Na2 can be used as a potential feed additive in broiler production.

Modulations of genes related to gut integrity, apoptosis, and immunity underlie the beneficial effects of Bacillus amyloliquefaciens CECT 5940 in broilers fed diets with different protein levels in a necrotic enteritis challenge model

Background

The ban of in-feed antimicrobial additives has negatively affected the poultry industry by causing necrotic enteritis (NE) to emerge in the flocks. Alternatives such as Bacillus probiotics have shown to be effective on eliminating the negative effects of this disease. Two experiments were conducted to investigate the effect of Bacillus amyloliquefaciens CECT 5940 (BA) in broiler chickens under NE challenge and/or fed diets with different protein levels.

Methods

In both experiments, 480 day-old mix-sexed Ross-308 broilers were arranged in a 2 × 2 factorial arrangement of treatments. In experiment 1, the factors were NE challenge (yes or no) and probiotic (yes or no). In experiment 2, the factors were dietary crude protein levels (standard or reduced) and probiotic (yes or no) and were used under NE challenge condition. Oral administration of Eimeria oocysts (day 9) followed by inoculation with Clostridium perfringens (day 14 and 15) was used to induce NE challenge. On day 16, two birds from each treatment were gavaged with fluorescein isothiocyanate-dextran (FITC-d) and blood samples were collected for gut integrity evaluation, and jejunal samples were collected for gene expression assay.

Results

In experiment 1, BA supplementation decreased caspase-3 (CASP3) (P < 0.001) and caspase-8 (CASP8) (P < 0.05) and increased occludin (OCLD) (P < 0.05) expression regardless of the challenge. Additionally, BA supplementation downregulated interfron-γ (IFN-γ) expression (P < 0.01) and upregulated immunoglobulin-G (IgG) (P < 0.01) and immunoglobulin-M (IgM) (P < 0.05) only in challenged birds. In experiment 2, the expression of genes encoding mucin-2 (MUC2) (P < 0.001), tight junction protein-1 (TJP1) (P < 0.05) and OCLD (P < 0.05) were upregulated by the addition of BA in the diet, regardless of the crude protein level. Further, BA supplementation downregulated INF-γ (P < 0.01) and upregulated immunoglobulin-A (IgA) (P < 0.05), IgM (P < 0.05) and IgG (P < 0.01) regardless of the crude protein level.

Conclusion

These findings suggest that supplementation of BA in broiler diets can improve gut health by modulation of genes related to the mucosal barrier, tight junction, and immunity in broilers challenged by unfavourable conditions such as NE challenge.

Probiotics (Direct-Fed Microbials) in Poultry Nutrition and Their Effects on Nutrient Utilization, Growth and Laying Performance, and Gut Health: A Systematic Review

Simple Summary

Probiotics are live bacteria, fungi, or yeasts that supplement the gastrointestinal flora and help to maintain a healthy digestive system, thereby promoting the growth performance and overall health of poultry. Probiotics are increasingly being included in poultry diets as an alternative to antibiotics. This systematic review provides a summary of the use of probiotics in poultry production and the potential role of probiotics in the nutrient utilization, growth and laying performance, and gut health of poultry.

Abstract

Probiotics are live microorganisms which, when administered in adequate amounts, confer health benefits to the host. The use of probiotics in poultry has increased steadily over the years due to higher demand for antibiotic-free poultry. The objective of this systematic review is to present and evaluate the effects of probiotics on the nutrient utilization, growth and laying performance, gut histomorphology, immunity, and gut microbiota of poultry. An electronic search was conducted using relevant keywords to include papers pertinent to the topic. Seventeen commonly used probiotic species were critically assessed for their roles in the performance and gut health of poultry under existing commercial production conditions. The results showed that probiotic supplementation could have the following effects: (1) modification of the intestinal microbiota, (2) stimulation of the immune system, (3) reduction in inflammatory reactions, (4) prevention of pathogen colonization, (5) enhancement of growth performance, (6) alteration of the ileal digestibility and total tract apparent digestibility coefficient, and (7) decrease in ammonia and urea excretion. Thus, probiotics can serve as a potential alternative to antibiotic growth promoters in poultry production. However, factors such as the intestinal health condition of birds, the probiotic inclusion level; and the incubation conditions, feedstuff, and water quality offered to birds may affect the outcome. This systematic review provides a summary of the use of probiotics in poultry production, as well as the potential role of probiotics in the nutrient utilization, growth and laying performance, and gut health of poultry.

Antimicrobial and mechanism of antagonistic activity of Bacillus sp. A2 against pathogenic fungus and bacteria: The implication on honey's regulatory mechanism on host's microbiota

Honey is thought to act against microbes and regulates microbiota balance, and this is mainly attributed to the enzymatic production of hydrogen peroxide, high osmolarity, and nonperoxidase factors, for example, lysozyme and botanical sources of nectar, while the effect of honey's probiotic is recently considered. The study of honey as source of beneficial microbes is understudied. The purpose of this study was to screen for the beneficial microorganisms in honey with antagonistic property against important pathogens and the mechanism of antimicrobial activity and thus play a beneficial role as probiotics. The results showed that one out of the fourteen bacterial isolates had antimicrobial activity and was identified as Bacillus Sp. A2 by 16S rRNA sequence and morphology. Antimicrobial activity of the isolate against C. albicans, E. coli, and S. aureus was confirmed by Agar well diffusion and liquid coculture assays, and the propagation of those microbes was significantly inhibited after treatment with the isolate Bacillus sp. A2 (p < .05) in comparison with untreated negative control and positive control (fluconazole, chloramphenicol, L. plantarum). The morphological changes including the distorted shape with indentations and leakages (SEM), damaged cell membrane, and cell wall with the disintegration and attachment of the Bacillus sp. A2 (TEM) in treated C. albicans were observed. Meanwhile, reactive oxygen species accumulation and decreased mitochondrial membrane potential were detected in treated C. albicans. These results revealed that the isolate Bacillus sp. A2 from honey has significant antimicrobial activity (p < .05) against C. albicans in comparison with untreated negative control and positive control L. plantarum, which depends on the accumulation of reactive oxygen species, mitochondrial damage, and the cell apoptosis. We concluded that the Bacillus sp. A2 possess the antimicrobial property, which may contribute to regulation of host's microbiota as a beneficial microbe or probiotic.

Effects of induced stress from the live LaSota Newcastle disease vaccination on the growth performance and immune function in broiler chickens

This study was conducted to assess the growth performance and immunological effects of vaccination-induced stress on broilers. The chickens were administered 0, 2, 4, 8, and 16 doses of live LaSota Newcastle disease (ND) vaccine and slaughtered on the 1st, 7th, 14th, and 21st day post vaccination. The results showed that the serum antibody titers after Newcastle disease virus (NDV) vaccination were elevated at day 7 post vaccination, peaked at day 14, then declined by day 21. Interestingly, the antibody titers peaked at 2 doses, and no further dose-dependent titer increases were observed. This study demonstrated that vaccination-induced stress increased serum adrenocorticotropic hormone and cortisol, affected growth performance (average daily gain, average daily feed intake, and feed conversion ratio), and triggered apoptosis in spleen lymphocytes by downregulating the ratio of Bcl-2 to BAX and upregulating the gene expressions of caspase-3 and -9, which was concordant with the activation of the enzymatic activities of caspase-3 and -9. This study suggests that NDV vaccine doses in broilers must be controlled judiciously because increasing the number of doses resulted in increased lymphocyte apoptosis while the peak of the antibody titer and optimal growth performance were achieved at a low number of doses (2 doses).

Effect of Carotenoids, Oligosaccharides and Anthocyanins on Growth Performance, Immunological Parameters and Intestinal Morphology in Broiler Chickens Challenged with Escherichia coli Lipopolysaccharide

This study was conducted to investigate the effect of carotenoid, oligosaccharide and anthocyanin supplementation in broiler diets under Escherichia coli lipopolysaccharide (LPS) challenge. Ross 308 chickens were fed 5 diets: basal diet (control diet), diet supplemented with β-glucan in 0.05% (positive control) and diets with 0.5% carotenoid-, oligosaccharide- or anthocyanin contents. On the 26th days of age, chickens were challenged intraperitoneally 2 mg LPS per kg of body weight. 12 h after injection, birds were euthanized, then spleen and ileum samples were collected. LPS induced increased relative mRNA expression of splenic (p = 0.0445) and ileal (p = 0.0435) interleukin-1β (IL-1β), which was lower in the spleen in carotenoid (p = 0.0114), oligosaccharide (p = 0.0497) and anthocyanin (p = 0.0303)-treated chickens compared to LPS-injected control birds. Dietary supplementation of carotenoids also decreased relative gene expression of splenic interleukin-6 (IL-6) (p = 0.0325). In the ileum, β-glucan supplementation showed lower relative mRNA expression of toll-like receptor 5 (TLR-5) (p = 0.0387) compared to anthocyanin treatment. Gene expression of both splenic and ileal interferon-α (IFN-α), interferon-γ (IFN-γ), toll-like receptor 4 (TLR-4) and toll-like receptor 5 (TLR-5) were not influenced by dietary supplements. In conclusion, carotenoids, oligosaccharides and anthocyanins could partially mitigate the immune stress caused by LPS challenge. All of the compounds impacted longer villus height (p < 0.0001), villus height:crypt depth ratios were higher after β-glucan (p < 0.0001) and anthocyanin (p = 0.0063) supplementations and thickened mucosa was observed in β-glucan (p < 0.0001), oligosaccharide (p < 0.0001) and anthocyanin (p = 0.048) treatments. All of these findings could represent a more effective absorption of nutrients.

Effects of berberine on the growth performance, antioxidative capacity and immune response to lipopolysaccharide challenge in broilers

This study evaluated the effects of berberine on growth performance, immunity, haematological parameters, antioxidant capacity, and the expression of immune response-related genes in lipopolysaccharide (LPS)-challenged broilers. We assigned 120 one-day-old male broilers (Ross 308) to two treatment groups; each group included two subgroups, each of which included six replicates of five birds per replicate. The experiment used a 2 × 2 factorial arrangement with berberine treatment (0 or 60 mg/kg dietary) and challenge status [injection of saline (9 g/L w/v) or LPS (1.5 mg/kg body weight)] as the main factors. On days 14, 16, 18 and 20, broilers were intraperitoneally injected with LPS or physiological saline. Blood and liver samples were collected on day 21. Dietary berberine supplementation significantly alleviated the compromised average daily gain and average daily feed intake (p < 0.05) caused by LPS. The LPS challenge led to increased lymphocyte and white blood cell (WBC) counts, malondialdehyde (serum and liver) content, and immunoglobulin G and M, tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) expression (p < 0.05) and significantly reduced serum total superoxide dismutase (T-SOD) activity (p < 0.05). Dietary berberine significantly mitigated the LPS-induced decreases in the mRNA expression of nuclear factor-kappa B (NF-κB), TNF-α, IL-1β, inducible nitrite synthase and cyclooxygenase-2 (p < 0.05) in the liver. In conclusion, berberine supplementation has a positive effect on LPS challenge, which may be related to the increase in antioxidant enzyme activity and inhibition of both NF-κB signalling and the expression of inflammatory mediators.

Effects of oral administration of essential oils on anti-immune stress, antimicrobial properties, and repairing the intestinal damage in broilers challenged by lipopolysaccharide

The aim of the present study was to evaluate the effects of oral administration of essential oils (carvacrol, thyme, and oregano) on anti-immune stress, antimicrobial properties, and repairing the intestinal damage caused by Salmonella enterica lipopolysaccharides (LPS) in broilers. A total of 100 Ross 308 broilers (21-d-old; 1.10 ± 0.11 kg) were randomly allocated to five groups: T1, basal diet + saline; T2, basal diet + LPS; T3, basal diet + 200 μL carvacrol oils + LPS; T4, basal diet + 200 μL thyme oils + LPS; T5, basal diet + 200 μL oregano oils + LPS, with 20 replicates each, and one chicken per replicate per cage. Those challenged by LPS resulted in an immune stress, which manifests as the abnormal growth (P < 0.05) in immune organs, and the content of immunoglobulin G (P < 0.05), tumor necrosis factor-α (P < 0.05), and the rectum temperature (P < 0.05) increased compared with other groups. The oral administration of essential oils controlled the immune stress to a certain extent. The essential oils could reduce harmful bacteria, such as Escherichia coli (P < 0.05) and Salmonella enumeration (P < 0.05), in vivo of broilers. Meanwhile, the essential oils repaired the intestinal damage, which showed a reduction in the villi height (P < 0.05) and goblet cell (P < 0.05) caused by LPS. In conclusion, the essential oils (carvacrol, thyme, and oregano essential oils) controlled the stress reaction and maintained intestinal health to a certain extent.

Effects of dietary methionine supplementation on growth performance, intestinal morphology, antioxidant capacity and immune function in intra-uterine growth-retarded suckling piglets

This study investigated the effects of dietary supplementation with L -methionine (L -Met), DL -methionine (DL -Met) and calcium salt of the methionine hydroxyl analog (MHA-Ca) on growth performance, intestinal morphology, antioxidant capacity and immune function in intra-uterine growth-retarded (IUGR) suckling piglets. Six normal birthweight (NBW) female piglets and 24 same-sex IUGR piglets were selected at birth. Piglets were fed nutrient adequate basal diet supplemented with 0.08% L -alanine (NBW-CON), 0.08% L -alanine (IUGR-CON), 0.12% L -Met (IUGR-LM), 0.12% DL -Met (IUGR-DLM) and 0.16% MHA-Ca (IUGR-MHA-Ca) from 7 to 21 days of age respectively (n = 6). The results indicated that IUGR decreased average daily milk (dry matter) intake and average daily gain and increased feed conversion ratio of suckling piglets (p < 0.05). Compared with the NBW-CON piglets, IUGR also impaired villus morphology and reduced antioxidant capacity and immune homeostasis in the intestine of IUGR-CON piglets (p < 0.05). Supplementation with L -Met enhanced jejunal villus height (VH) and villus area and ileal VH of IUGR piglets compared with IUGR-CON piglets (p < 0.05). Similarly, DL -Met supplementation increased VH and the ratio of VH to crypt depth in the jejunum compared with IUGR-CON pigs (p < 0.05). Supplementation with L -Met and DL -Met (0.12%) tended to increase reduced glutathione content and reduced glutathione: oxidized glutathione ratio and decrease protein carbonyl concentration in the jejunum of piglets when compared with the IUGR-CON group (p < 0.10). However, supplementation with MHA-Ca had no effect on the intestinal redox status of IUGR piglets (p > 0.10). In conclusion, supplementation with either L -Met or DL -Met has a beneficial effect on the intestinal morphology and antioxidant capacity of IUGR suckling piglets.