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This experiment was conducted to evaluate the effects of wheat bran (WB) and antibiotics on growth performance, intestinal immunity, barrier function, and microbial composition in broiler chickens. A total of 168 one-day-old male Arbor Acre chicks were allocated to 3 treatments consisting of 7 replicates with 8 birds per replicate. The 3 treatments were: an antibiotic-free control diet (control, CON), CON 1 75 mg/kg chlortetracycline as an antibiotic growth promoter (AGP), and CON 1 3% WB. Birds fed AGP and WB had greater (P, 0.05) ADG during days 1 to 21 and lower (P, 0.05) feed-to-gain ratio during each phase than those fed CON. The WB supplementation reduced (P, 0.05) serum concentrations of tumor necrosis factor-a and diamine oxidase activity compared with CON on both day 21 and 42. The AGP and WB supplementation decreased (P, 0.05) interleukin- 1b concentration in jejunal mucosa on day 21 and increased (P, 0.05) secretory immunoglobulin A concentration in jejunal mucosa on day 21 and 42. The relative expression of occludin in jejunal mucosa was upregulated (P, 0.05) in WB than in CON on day 21. Moreover, both AGP and WB supplementation upregulated (P, 0.05) the relative expression of zonula occludens-1 in jejunal mucosa on day 21 and 42. The WB supplementation enhanced the a-diversity of cecal microbiota, as evidenced by the increased Shannon index (P, 0.05). At the phylum level, the phylum Firmicutes was enriched (P, 0.05) in WB. At the genus level, the WB supplementation enriched (P, 0.05) Lachnoclostridium and Butyricicoccus. The WB supplementation increased (P, 0.05) cecal total short chain fatty acids concentrations on day 21 and 42, and butyric acid concentrations on day 42 compared with CON. Collectively, supplementation of 3% WB could promote growth by improving intestinal immunity, barrier function, and microbial composition in broilers. Thus, WB may have a role in replacing antibiotics for improved growth performance and intestinal health in broilers. [ABSTRACT FROM AUTHOR]

Probiotics are increasingly recognized for their capacity to combat pathogenic bacteria. In this study, we isolated a strain of Ligilactobacillus salivarius XP132 from the gut microbiota of healthy chickens. This strain exhibited resistance to low pH and bile salts, auto-aggregation capabilities, and the ability to co-aggregate with pathogenic Salmonella. The in vitro antibacterial activity of Ligilactobacillus salivarius XP132 was tested using an Oxford cup antibacterial test, and the results showed that Ligilactobacillus salivarius XP132 exhibited broad-spectrum antibacterial activity, with especially strong antibacterial activity against Salmonella. In animal experiments with white feather broilers and specific-pathogens-free (SPF) chickens, we orally administered 1 × 10 9 CFU XP132 live bacteria per chicken per day, and detected the content of Salmonella in the liver, spleen, intestinal contents, and eggs of the chickens by RT-qPCR. Oral administration of Lactobacillus salivarius XP132 group significantly reduced the levels of Salmonella in chicken liver, spleen, intestinal contents and eggs, and the oral administration of Ligilactobacillus salivarius XP132 significantly inhibited the horizontal and vertical transmission of Salmonella in SPF chickens and white-feathered broilers. After oral administration of XP132, the production of chicken serum anti-infective cytokine IFN-γ was also significantly up-regulated, thereby enhancing the host's ability to resist infection. In addition, the production of various serum inflammatory cytokines, including IL-1β, IL-6, IL-8, and TNF-α, was down-regulated, leading to significant amelioration of the inflammatory response induced by S. Pullorum in chickens. These findings suggest that Ligilactobacillus salivarius XP132 possesses potent antibacterial and immunomodulatory properties that effectively prevent both horizontal and vertical transmission of Salmonella Pullorum, highlighting its potential as a valuable tool for the prevention and control of Salmonella disease., Competing Interests: DISCLOSURES The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Understanding the characteristics of bacteriophages is crucial for the optimization of phage therapy. In this study, the biological and genomic characteristics of coliphage LHE83 were determined and its synergistic effects with different types of antibiotics against E. coli E82 were investigated. Phage LHE83 displayed a contractile tail morphology and had a titer of 3.02 × 10 9 pfu/mL at an optimal MOI of 0.01. Meanwhile, phage LHE83 exhibited good physical and chemical factors tolerance. The 1-step growth analysis revealed a latent period of approx. 10 min with a burst size of 87 pfu/infected cell. Phage LHE83 belongs to the genus Dhakavirus. Its genome consists of 170,464 bp with a 40% GC content, and a total of 268 Open Reading Frames (ORF) were predicted with no detected virulent or resistant genes. ORF 213 was predicted to encode the receptor binding protein (RBP) and confirmed by the antibody-blocking assay. Furthermore, a phage-resistant strain E. coli E82R was generated by co-culturing phage LHE83 with E. coli E82. Genomic analysis revealed that OmpA served as the receptor for phage LHE83, which was further confirmed by phage adsorption assay using E. coli BL21ΔOmpA, E. coli BL21ΔOmpA: OmpA and E. coli BL21:OmpA strains. Additionally, a synergistic effect was observed between phage LHE83 and spectinomycin against the drug-resistant strain E. coli E82. These results provide a theoretical basis for understanding the interactions between phages, antibiotics, and host bacteria, which can assist in the clinical application of phages and antibiotics against drug-resistant bacteria., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

This research was conducted to determine the effects of natural capsaicin extract (NCE) as an alternative to the antibiotic (chlortetracycline, CTC) on growth performance, antioxidant capacity, immune function, and meat quality of broiler chickens. A total of 168 one-day-old Arbor Acre male broiler chickens with an average weight of 46.4 ± 0.6 g were randomly allotted to 3 dietary treatments, with 7 replicates per treatment and 8 broilers per pen. These 3 dietary treatments included a corn-soybean meal basal diet (CON), a basal diet + 75 mg/kg CTC (CTC), and a basal diet + 80 mg/kg NCE (NCE). Broilers from the NCE group showed higher average daily gain compared to broilers from the CON group at all stages (P < 0.05). On d 42, NCE supplementation improved dietary nitrogen-corrected apparent metabolizable energy compared to nonsupplemented or CTC-supplemented diets (P < 0.05). The digestibility of organic matter and crude protein were higher in the NCE diet than in the CON or CTC diets (P < 0.05). Higher relative weight of bursa of Fabricius was observed in broilers fed NCE diets compared with CON (P < 0.05). Pancreatic trypsin and lipase activities were significantly increased in the NCE group compared with those in the CON group (P < 0.05). The value of lightness (L*) of breast muscles from broilers fed NCE diets was significantly lower compared to those fed CON diets (P < 0.05). Broilers fed NCE diets also had higher levels of serum total antioxidant capacity, glutathione peroxidase, superoxide dismutase, and lower levels of interleukin-1β, and tumor necrosis factor-α compared with broilers fed CON diets (P < 0.05). The liver catalase activity of broilers was also significantly increased in the NCE group than the CON group (P < 0.05). In addition, broilers from NCE group had lower concentrations of serum urea-N, low-density lipoprotein cholesterol, and total cholesterol, and higher concentration of growth hormone compared with those from the CON group (P < 0.05). Therefore, we concluded that supplementation of 80 mg/kg of NCE in diets could improve growth performance, nutrient digestibility, antioxidant status, immune function, and meat quality in broilers., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Duck Tembusu virus (DTMUV) and duck plague virus (DPV) are typical DNA and RNA viruses of waterfowl, causing drastic economic losses to the duck farm industry in terms of high mortality and decreased egg production. These 2 viruses reappear from time to time because the available vaccines fail to provide complete immunity and no clinical antiviral drugs are available for them. In the present study, we evaluated the antiviral activity of SC75741 for DTMUV, DPV, and the model virus, vesicular stomatitis virus infection in duck cells. SC75741, a nuclear factor-kappa B (NF-κB)-specific inhibitor in mammal cells, revealed the highest antiviral activity among the inhibitors specific to c-Jun NH 2 -terminal kinase, extracellular signal-regulated kinase, p38 mitogen-activated protein kinase (p38), and NF-κB signaling. The antiviral activity of SC75741 was dose-dependent and showed effects in different duck cell types. Time-addition and duration assay demonstrated that SC75741 inhibited virus infection in the middle of and after virus infection at least for 72 h in duck embro fibroblast cells. The DPV viral adsorption and genomic copy number were reduced, indicating that SC75741 blocks the phase of the virus life cycle at viral entry and genomic replication. In addition, SC75741 enhanced the expression of interferon only when stimulator of interferon genes (STING) was overexpressed or pre-activated by the virus infection, suggesting that SC75741 acts as a STING agonist. In conclusion, SC75741 is a candidate antiviral agent for DTMUV and DPV., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

To determine the effects of normal and low dietary calcium (Ca) and phosphorus (P) levels and 25-hydroxycholecalciferol (25-OH-D 3 ) supplementation on performance, serum antioxidant status, meat quality, and bone properties of broilers, 224 1-day-old Arbor Acre male broilers were used in this study. Broilers were allotted randomly to 1 of 4 treatments in a 2 × 2 factorial arrangement that included normal or low Ca and P diet with or without 69 μg/kg 25-OH-D 3 . The trial consists of a starter phase from day 1 to 21 and a grower phase from day 22 to 42. Dietary 25-OH-D 3 supplementation increased (P < 0.05) average daily weight gain from day 22 to 42 and decreased feed conversation ratio from day 22 to 42 and day 0 to 42. On day 21, 25-OH-D 3 increased serum concentrations of total antioxidant capacity (T-AOC), catalase (CAT), and glutathione peroxidase in broilers fed low Ca and P diet (Interaction, P < 0.05). 25-hydroxycholecalciferol significantly decreased serum malondialdehyde concentration. Dietary Ca and P deficiencies significantly decreased serum Ca and P concentrations and increased serum parathyroid hormone (PTH) concentration, and serum Ca and 25-OH-D 3 concentrations were significantly increased by 25-OH-D 3 supplementation. On day 42, serum T-AOC and CAT concentrations were decreased by dietary Ca and P deficiencies without 25-OH-D 3 (Interaction, P < 0.05) and unaffected by dietary Ca and P deficiencies with 25-OH-D 3 . Dietary Ca and P deficiencies significantly decreased Ca, P, and alkaline phosphatase concentrations and increased PTH concentration in serum. Dietary 25-OH-D 3 increased (P < 0.05) serum Ca and 25-OH-D 3 concentrations and decreased (P < 0.05) serum tartrate-resistant acid phosphatase concentration. The interaction between CaP level and 25-OH-D 3 was observed (P < 0.05) for tibial Ca content and femoral bone density. 25-hydroxycholecalciferol significantly increased tibial breaking strength. These data indicated that 25-OH-D 3 supplementation at 69 μg/kg increased growth performance in some periods, enhanced serum antioxidant capacity, and improved bone mineralization and breaking strength of broilers., (Copyright © 2020. Published by Elsevier Inc.)

This experiment aims to determine the effects of Forsythia suspense extract (FSE) as an antibiotic substitute on performance, antioxidant status, anti-inflammatory function, intestinal morphology, and meat fatty acid deposition in broilers. 192 male Arbor Acre broilers (1-day-old, weighing 45.6 ± 1.3 g) were randomly allocated to 3 treatments, 8 replicate pens per treatment, 8 broilers per pen. The treatments contain a control diet (corn-soybean meal basal diet, CTL), an antibiotic diet (basal diet + 75 mg/kg chlortetracycline, CTC), and an FSE diet (basal diet + 100 mg/kg FSE; FSE). The experiment includes phase 1 (day 1 to 21) and 2 (day 22 to 42). Compared with CTL and CTC, broilers supplemented with FSE showed higher (P < 0.05) ADG and ADFI in phase 2 and overall (day 1 to 42). On day 21, serum catalase and total antioxidant capacity contents were enhanced (P < 0.05) in broilers fed FSE compared with CTL. On day 42, broilers fed FSE showed increased (P < 0.05) serum superoxide dismutase and glutathione peroxidase contents, and enhanced (P < 0.05) apparent total tract digestibility of dry matter, organic matter, gross energy, total carbohydrates, and phosphorus, as well as reduced (P < 0.05) nitrogen and phosphorus excretion in feces compared with CTL. These broilers also showed decreased (P < 0.05) n-6/n-3 polyunsaturated fatty acid ratio in thigh meat, and tumor necrotic factor-alpha, interleukin-1β and interleukin-6 contents in the liver on day 42 compared with CTL. The villus height was increased (P < 0.05) in the duodenum, jejunum, and ileum of broilers fed FSE compared with CTL. In conclusion, dietary F.suspense extract supplementation as a chlortetracycline substitute under non-challenge conditions enhanced performance via the improvement of nutrient digestibility, antioxidant status, anti-inflammatory function, and intestinal morphology in broilers. Moreover, F.suspense extract may also benefit environment by reducing nitrogen and phosphorus excretion and benefit human health via modulating meat fatty acid profiles in broilers., (Copyright © 2020. Published by Elsevier Inc.)