Explore the vast range of titles available.

Background Exposure to heat stress suppresses poultry immune responses, which can increase susceptibility to infectious diseases and, thereby, intensify the negative effects of heat on poultry welfare and performance. Identifying genes and pathways that are affected by high temperatures, especially heat-induced changes in immune responses, could provide targets to improve disease resistance in chickens. This study utilized RNA-sequencing (RNA-seq) to investigate transcriptome responses in the bursa of Fabricius, a primary immune tissue, after exposure to acute heat stress and/or subcutaneous immune stimulation with lipopolysaccharide (LPS) in a 2 × 2 factorial design: Thermoneutral + Saline, Heat + Saline, Thermoneutral + LPS and Heat + LPS. All treatments were investigated in two chicken lines: a relatively heat- and disease-resistant Fayoumi line and a more susceptible broiler line. Results Differential expression analysis determined that Heat + Saline had limited impact on gene expression ( N  = 1 or 63 genes) in broiler or Fayoumi bursa. However, Thermoneutral + LPS and Heat + LPS generated many expression changes in Fayoumi bursa ( N  = 368 and 804 genes). Thermoneutral + LPS was predicted to increase immune-related cell signaling and cell migration, while Heat + LPS would activate mortality-related functions and decrease expression in WNT signaling pathways. Further inter-treatment comparisons in the Fayoumi line revealed that heat stress prevented many of the expression changes caused by LPS. Although fewer significant expression changes were observed in the broiler bursa after exposure to Thermoneutral + LPS ( N  = 59 genes) or to Heat + LPS ( N  = 146 genes), both treatments were predicted to increase cell migration. Direct comparison between lines (broiler to Fayoumi) confirmed that each line had distinct responses to treatment. Conclusions Transcriptome analysis identified genes and pathways involved in bursal responses to heat stress and LPS and elucidated that these effects were greatest in the combined treatment. The interaction between heat and LPS was line dependent, with suppressive expression changes primarily in the Fayoumi line. Potential target genes, especially those involved in cell migration and immune signaling, can inform future research on heat stress in poultry and could prove useful for improving disease resistance.

The bursa of Fabricius (BF) is a unique primary lymphoid organ critical for B cell development in its specialized follicular microenvironment. Although the role of the follicular medulla required for B cell maturation is well characterized, the cellular components and function of the ontogenetically later emerging cortex remain less understood. Here, we combined immunocytochemistry, RNAscope, cell culture, and embryo manipulation techniques to investigate the origin and structure of the cortical compartment. Immunostaining of adult BF revealed a heterogeneous B cell distribution in the cortex, with chB6+/CXCR4 high cells in the outer region and CXCR4 low/dim cells adjacent to the cortico-medullary border. The cortex is supported by CXCL12+/desmin+/vimentin+ mesenchymal reticular cells producing extracellular matrix (ECM), including tenascin-C, which is enriched in the CXCR4 low/dim region. Embryonic expression of tenascin-C coincides with the accumulation of CXCR4+ B cell precursors in the presumptive cortical compartment. Functional studies demonstrate that tenascin-C inhibits embryonic CXCR4+ B cell migration, with overexpression disrupting follicle formation. These findings highlight tenascin-C as a key regulator of B cell migration in the embryonic BF and emphasize the importance of a tenascin-C-free mesenchymal environment for the homing of CXCR4 + B cell precursors during development. In adults, the complementary expression patterns of tenascin-C and CXCR4 molecules suggest that downregulation of CXCR4 is required for B cell migration through the CXCL12-tenascin-C-rich cortex before exiting the BF.

Cadmium (Cd) is a serious environmental pollutant affecting various tissues/organs in broilers and compromising their immunological function and productivity. Therefore, the current study aimed to investigate Cd-induced immunotoxicity and potential immunoprotective effect of rutin nanoparticles (RNPs) in the bursal tissue of broilers. A total number of 150 chicks from the Hubbard breed were randomly divided into 5 groups. Group I was fed on standard basal diet (SD) with normal drinking water (DW), Group II received SD containing RNPs (50 mg/kg feed) with DW, Group III fed on SD and DW containing Cd (150 mg/L), Group IV co-treated with rutin-enforced SD (50 mg/kg diet) and DW containing Cd (150 mg/L), and finally, Group V co-supplemented with RNP-enhanced SD (50 mg/kg diet) DW containing Cd (150 mg/L). Productive performance, economic efficiency, oxidative biomarkers, histopathological changes, and the expression level of TLR-4, HSP-70, caspase 3, NF- κ B, Bcl-2, and Bax were assessed in the BF tissue. Cd led to severe production and economic losses in exposed birds with a marked surge of oxidative biomarkers, pro-inflammatory cytokines, and histopathological changes in the bursal tissue which could be explained through upregulation of the Hsp70/TLR4/NF- κ B molecular pathway in the BF tissue. Meanwhile, RNPs could alleviate most of these changes and prevail optimistic immunomodulatory properties which subsequently could enhance broilers’ productivity when incorporated in their diets. Graphical Abstract

Frozen shoulder is a common, fibro-proliferative disease characterised by the insidious onset of pain and progressively restricted range of shoulder movement. Despite the prevalence of this disease, there is limited understanding of the molecular mechanisms underpinning the pathogenesis of this debilitating disease. Previous studies have identified increased myofibroblast differentiation and proliferation, immune cell influx and dysregulated cytokine production. We hypothesised that subpopulations within the fibroblast compartment may take on an activated phenotype, thus initiating the inflammatory processes observed in frozen shoulder. Therefore, we sought to evaluate the presence and possible pathogenic role of known stromal activation proteins in Frozen shoulder. Shoulder capsule samples were collected from 10 patients with idiopathic frozen shoulder and 10 patients undergoing shoulder stabilisation surgery. Fibroblast activation marker expression (CD248, CD146, VCAM and PDPN, FAP) was quantified using immunohistochemistry. Control and diseased fibroblasts were cultured for in vitro studies from capsule biopsies from instability and frozen shoulder surgeries, respectively. The inflammatory profile and effects of IL-1β upon diseased and control fibroblasts was assessed using ELISA, immunohistochemistry and qPCR. Immunohistochemistry demonstrated increased expression of fibroblast activation markers CD248, CD146, VCAM and PDPN in the frozen shoulder group compared with control (p < 0.05). Fibroblasts cultured from diseased capsule produced elevated levels of inflammatory protein (IL-6, IL-8 & CCL-20) in comparison to control fibroblasts. Exposing control fibroblasts to an inflammatory stimuli, (IL-1ß) significantly increased stromal activation marker transcript and protein expression (CD248, PDPN and VCAM). These results show that fibroblasts have an activated phenotype in frozen shoulder and this is associated with inflammatory cytokine dysregulation. Furthermore, it supports the hypothesis that activated fibroblasts may be involved in regulating the inflammatory and fibrotic processes involved in this disease.

Infectious bursal disease virus (IBDV) is an acute and highly infectious RNA virus known for its immunosuppressive capabilities, chiefly inflicting rapid damage to the bursa of Fabricius (BF) of chickens. Current clinical control of IBDV infection relies on vaccination. However, the emergence of novel variant IBDV (nVarIBDV) has posed a threat to the poultry industry across the globe, underscoring the great demand for innovative and effective vaccines. Our previous studies have highlighted the critical role of IBDV VP5 as an apoptosis-inducer in host cells. In this study, we engineered IBDV mutants via a reverse genetic system to introduce amino acid mutations in VP5. We found that the mutant IBDV-VP5/3m strain caused reduced host cell mortality, and that strategic mutations in VP5 reduced IBDV replication early after infection, thereby delaying cell death. Furthermore, inoculation of chickens with IBDV-VP5/3m effectively reduced damage to BF and induced neutralizing antibody production comparable to that of parental IBDV WT strain. Importantly, vaccination with IBDV-VP5/3m protected chickens against challenges with nVarIBDV, an emerging IBDV variant strain in China, reducing nVarIBDV loads in BF while alleviating bursal atrophy and splenomegaly, suggesting that IBDV-VP5/3m might serve as a novel vaccine candidate that could be further developed as an effective vaccine for clinical control of IBD. This study provides a new clue to the development of novel and effective vaccines.

Bursa of Fabricius (BF) is a primary lymphoid organ in birds, crucial for lymphocyte development and immune function. This study investigates age‐related alterations in the histomorphology and ultrastructure of the bursal tissue in green‐winged teal (Anas crecca) at 8th and 24th weeks of age. Twenty ducks were examined, and the sample tissues were collected post‐euthanasia for histological and scanning electron microscopy (SEM) analyses. At the 8th week, the histological sections exhibited normal lymphocyte distribution and structural organization, characterized by a well‐developed muscular layer and plicae. In contrast, by the 24th week, significant involution was observed, marked by reduced bursal weight, diminished muscular layer and increased fibrosis. Histological changes included necrosis and depletion of lymphocytes, alongside alterations in the follicular‐associated epithelium. SEM revealed collagen fibre spreading and loss of microvilli, indicating advanced involution. This study highlights the developmental and involutionary stages of the organ in A. crecca, providing essential insights into the age‐dependent changes in this critical immune organ. This is the first report detailing these histomorphometric and ultrastructural alterations in A. crecca, highlighting the age‐dependent nature of these changes, besides contributing to our understanding of avian immunology. This scientific diagram illustrates age‐related changes in the Bursa of Fabricius (BF) of green‐winged teal (Anas crecca) ducks at two developmental stages. In the 8th week, the BF shows maximum maturation with peak morphometric measurements (body weight, bursal dimensions), the thickness of cortex and medulla layers and well‐developed ultrastructure, including microvilli and regular borders. By the 24th week, the BF undergoes involution with decreased measurements, reduced tissue thickness and structural deterioration, including absent microvilli, irregular borders and collagen fibre deposition. The study demonstrates the natural developmental progression from functional maturity to age‐related regression in this important immune organ of waterfowl.

Aflatoxin B1 (AFB1) is a serious threat to the poultry industry. Proanthocyanidins (PCs) demonstrates a broad range of biological, pharmacological, therapeutic, and chemoprotective properties. The aim of this study was to investigate the ameliorative effects of PCs against AFB1-induced histopathology, oxidative stress, and apoptosis via the mitochondrial pathway in the bursa of Fabricius (BF) of broilers. One hundred forty-four one-day old Cobb chicks were randomly assigned into four treatment groups of six replicates (6 birds each replicate) for 28 days. Groups were fed on the following four diets; (1) Basal diet without addition of PCs or AFB1 (Control); (2) basal diet supplemented with 1 mg/kg AFB1 from contaminated corn (AFB1); (3) basal diet supplemented with 250 mg/kg PCs (PCs); and (4) basal diet supplemented with 1 mg/kg AFB1 + 250 mg/kg PCs (AFB1+ PCs). The present study results showed that antioxidant enzymes activities of total superoxide dismutase (T-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione S-transferase (GST) in AFB1 treated group were (p < 0.05) decreased, whereas malondialdehyde (MDA) contents were significantly increased in comparison with the control group. Furthermore, we found that dietary PCs treatment ameliorated AFB1-induced oxidative stress in the BF through inhibiting the accumulation of MDA content and enhancing the antioxidant enzymes activities (T-SOD, CAT, GSH-Px, and GST). Similarly, PCs markedly enhanced messenger RNA (mRNA) expression of antioxidant genes (SOD, CAT, GPx1, and GST) in comparison with AFB1 group. Moreover, histological results showed that PCs alleviated AFB1-induced apoptotic cells in the BF of broilers. In addition, both mRNA and protein expression results manifested that mitochondrial-apoptosis-associated genes (Bax, caspase-9, caspase-3, and p53 and cytochrome c) showed up-regulation, while (Bcl-2) showed down-regulation in AFB1 fed group. The supplementation of PCs to AFB1 diet significantly reversed the mRNA and protein expression of these apoptosis-associated genes, as compared to the AFB1 group. Our results demonstrated that PCs ameliorated AFB1-induced oxidative stress by modulating the antioxidant defense system and apoptosis in the BF through mitochondrial pathway in broilers.

Scabies infestation is a major parasitic disease affecting both human and animal health worldwide. This study aimed to determine the distribution of scabies infestation in stray dogs in Bursa province. The study material was obtained from stray dogs suspected of mange kept in a municipal shelter in Bursa between June 2020 and February 2022. Samples from stray dogs were examined in a laboratory, and dogs with scabies were determined. During the study, samples were collected from 205 (115 males, 90 females) scabies-suspected stray dogs, 58 (28.29%) of which had scabies. spp. were detected in 35 of the positive dogs (60.34%) ( ), 19 (32.76%) , 2 (3.44%) mixed infestation ( and ), and 2 (3.44%) agents. It was determined that 32 (55.17%) of 58 scabies-positive dogs were male and 26 (44.83%) were female. The association of infestations with age, season, and sex has not been found to be statistically meaningful. This study identified scabies agents and their prevalence rate in stray dogs of Bursa province, Türkiye.

Background The molecular mechanisms underlying stress-influenced immune function of chicken ( Gallus Gallus ) are not clear. The stress models can be established effectively by feeding chickens corticosterone (CORT) hormone. The bursa of Fabricius is a unique central immune organ of birds. RNA-Seq technology was used to investigate differences in the expression profiles of immune-related genes and associated pathways in the bursa of Fabricius to clarify molecular mechanisms. The aim of this study was to broaden the understanding of the stress-influenced immune function in chickens. Results Differentially expressed genes (DEGs) in the bursa of Fabricius between experimental group (basal diet with added CORT 30 mg/kg; C_B group) and control group (basal diet; B_B group) were identified by using RNA-seq technology. In total, we found 1434 significant DEGs (SDEGs), which included 199 upregulated and 1235 downregulated genes in the C_B group compared with the B_B group. The immune system process GO term was the top significantly GO term, including MYD88 , TLR4 , IL15 , VEGFA gene and so on. The cytokine-cytokine receptor interaction pathway and the Toll-like receptor signaling pathway were the key pathways affected by stress. The protein-protein interaction (PPI) analysis of the SDEGs showed that VEGFA , MyD88 and IL15 were hub genes and module analysis showed that MYD88 , TLR4 and VEGFA play important roles in response to stress. Conclusion This study showed that the VEGFA and ILs (such as IL15 ) via the cytokine-cytokine receptor interaction pathway, MYD88 and TLR4 via the Toll-like receptor signaling pathway may play important roles in the regulation of immune function under stress condition with CORT administration. The results of this study provide a reference for further studies of the molecular mechanisms of stress-influenced immune function.