Search Results (3,951)

This study evaluated graded dietary doses of Saccharomyces cerevisiae postbiotic (0, 1.25, 2.5 and 5 g kg⁻¹) on growth, feed utilization, serum biochemistry, expression of IGF-1, SOD2, IL-1β, IL-10 and IgM, and resistance to Fusarium oxysporum in Nile tilapia (Oreochromis niloticus; 35.1 ± 0.9 g) after 30 and 60 days of feeding. Although the 5 g Kg⁻¹ inclusion significantly increased WG (59.4 ± 0.9) and SGR (1.5 ± 0.0) and decreased FCR (0.8 ± 0.0), significant positive effects on multiple endpoints were also recorded at 1.25 and 2.5 g/kg. Serum total protein and globulin rose with increasing dose and feeding duration, while albumin showed limited change, lowering the A/G ratio. AST remained unchanged. Creatinine and glucose declined with postbiotic supplementation; the glucose reduction effect was dose-dependent, whereas creatinine was unaffected by feeding duration. The highest gene expression of hepatic IGF-1, SOD2, IL-1β, and IL-10 and splenic IL-1β, IL-10, and IgM was in T3 at both checkpoints; however, the highest gene expression of intestinal IL-1β, IL-10, and IgM expression was in T1 at both time points. The pathogenicity experiment showed a significant survival against F. oxysporum (p < 0.0001) compared to controls. The results suggested that dietary S. cerevisiae postbiotic improved growth, biochemical and molecular responses, and survival of Nile tilapia against F. oxysporum. Full article

Atopic dermatitis (AD) and food allergy frequently coexist during early childhood and are increasingly linked through interactions within the gut–skin axis. We evaluated the clinical outcomes of an integrated nutritional and microbiome-oriented management strategy in children with food allergy-associated AD under real-world conditions. This prospective, two-center, real-world observational cohort study included 85 children (median age, 11 months) with AD diagnosed according to the Hanifin–Rajka criteria and confirmed IgE- and/or non-IgE-mediated food allergy. Participants received individualized nutritional and microbiome-oriented management comprising elimination diets, conventional topical therapy, microbiome-directed interventions, and nutritional supplementation tailored to their clinical, allergological, and microbiological profile. Disease severity was assessed using the Scoring Atopic Dermatitis (SCORAD) index at baseline and after approximately 1 and 3 months of follow-up. Cow’s milk, egg, and wheat were the predominant food allergens, and 69.4% of children were polyallergic. SCORAD decreased significantly during follow-up, with a mean relative reduction of 51.6% and 63.5% of participants achieving a SCORAD50 response. Food allergy burden independently predicted baseline disease severity, whereas documented gut dysbiosis was associated with polyallergy and greater absolute clinical improvement, although this association lost statistical significance after adjustment for baseline disease severity and should therefore not be interpreted as a favorable prognostic effect of dysbiosis. Baseline SCORAD remained the strongest independent predictor of clinical improvement. Integrated nutritional and microbiome-oriented management was associated with substantial clinical improvement and may represent a valuable adjunct to standard care in children with food allergy-associated AD. Because of the observational, uncontrolled design, these findings describe associations rather than causal treatment effects. These findings support further evaluation of personalized nutritional strategies in randomized controlled trials. Full article

Background: Staphylococcus aureus (SA) causes septicemia and arthritis, eventually resulting in substantial economic losses and health hazards in poultry. Lethal electron beam (eBeam) treatment kills bacteria while preserving surface epitopes. Methods: This study compared broiler chicken immune responses (local and systemic) after eBeam-killed (eB) or formalin-killed (FK) SA injections. The vaccine (sham) control was endotoxin-free PBS. This study contained six treatments (trt) with five chickens/trt, with vaccine trts divided into two groups, A and B. Group A received in ovo vaccine/sham treatments (phase 1) initially. At 34 d of age, the pulps of growing feathers (GFs) received intradermal (i.d.) injections of the respective trt to elicit booster and primary responses in groups A and B, respectively. Blood was collected to analyze leukocyte populations and plasma SA-specific antibody levels. Additionally, in phase 2, GFs were collected to assess leukocyte presence in GF pulps. Two-way ANOVA was conducted to test the effects of treatment, time, and their interactions, followed by Tukey’s HSD tests at p < 0.05 for statistical significance. Results: Early in phase 1, the eB group had increased SA-specific IgM, IgA, and total lymphocyte concentrations compared with FK. In phase 2, FK and eB i.d. vaccines increased total lymphocyte and T cell proportions in GF pulps compared with sham. In blood, the recall eB vaccination increased monocytes, B cells, CD8+ T cells, and total lymphocytes, while the recall FK vaccination increased heterophils (p < 0.05). Conclusions: Improved early protection at mucosal surfaces may be reflected by higher plasma levels of SA-specific IgM and IgA following in ovo eBeam-killed-SA vaccination. Additionally, both eB-SA and FK-SA vaccines stimulated robust local inflammatory responses dominated by lymphocytes in GF pulps. Full article

Bovine coronavirus (BCoV) is a major cause of respiratory and enteric diseases in cattle, resulting in substantial economic losses to the global cattle industry. Next-generation epitope-focused vaccines require conserved neutralizing determinants to achieve broad protective efficacy across circulating variants. Here, we applied a reverse-vaccinology and immunoinformatics-guided strategy to identify conserved linear B-cell epitope candidates on the BCoV spike protein. Using ABCPred (16 aa; threshold score 0.51), 139 putative linear B-cell epitopes were predicted, and 10 candidates (B1–B10) were selected based on antigenicity, allergenicity/toxicity filters, and Shannon-entropy-based conservation (≥95%). Each candidate was displayed on Helicobacter pylori ferritin and TEM confirmed the formation of self-assembled nanocages. BALB/c mice (n = 6 per group) were subcutaneously immunized with 50 μg of each epitope–ferritin fusion protein emulsified 1:1 with Montanide ISA 201 in a prime–boost regimen (at a 14-day interval), and sera were collected 14 days after the booster immunization. All 10 constructs induced BCoV-specific binding IgG (endpoint titers ranging from 1:2667 to 1:11,733), but only B1, B2, B4, B6, B7, and B8 elicited detectable in vitro neutralizing activity against both representative strains, whereas B3, B5, B9, and B10 remained below the detection limit (<1:8). Neutralizing titers were 1:24–1:99 for the enteric strain XHD4 and 1:27–1:88 for the respiratory strain HXD1, with no significant difference observed between the two strains (p > 0.05). Overall, these findings identify six conserved B-cell epitope candidates capable of eliciting neutralizing antibody responses against both representative enteric and respiratory field strains, providing experimental evidence to support epitope-focused BCoV vaccine design. Full article

Background/Objectives: Batai orthobunyavirus (BATV) is an emerging mosquito-borne zoonotic pathogen for which no licensed vaccine is currently available. The viral envelope glycoprotein plays an important role in viral attachment and host immune recognition, making it a potential target for rational vaccine design. Methods: In this study, an immunoinformatics-based framework was used to design and evaluate a multi-epitope vaccine candidate targeting the BATV envelope glycoprotein. Selected B-cell, cytotoxic T-lymphocyte (CTL), and helper T-lymphocyte (HTL) epitopes were assembled using appropriate linkers and a human β-defensin adjuvant. Population coverage and in silico immune simulations were conducted to evaluate the potential breadth and magnitude of immune response. Results: The final vaccine construct demonstrated favorable physicochemical characteristics, high predicted antigenicity (0.7959), and non-allergenic properties while maintaining favorable predicted structural characteristics and broad predicted population coverage (99.92%). Structural docking revealed a stable interaction between the vaccine construct and human TLR4, with a weighted docking score of −1194.8, suggesting favorable molecular recognition and receptor engagement. Normal Mode Analysis further supported the structural stability and conformational integrity of the vaccine receptor complex. Immune simulation predicted robust primary and secondary immune responses characterized by elevated IgM and IgG antibody production, sustained memory cell formation, and strong IFN-γ and IL-2 responses, indicating the potential to elicit balanced humoral and cellular immunity. Conclusions: This study presents a structurally optimized and validated multiepitope vaccine candidate against the emerging Batai orthobunyavirus. These computational findings identified a promising vaccine candidate for further investigation; however, its immunogenicity, safety, and protective efficacy before further vaccine development can be considered. Full article

Though a number of Eimeria species have been described in geese, the host responses to these parasites at the molecular level have yet to be explored. In the present study, fresh fecal samples were collected for single-oocyst isolation. The recovered oocysts were identified based on molecular analysis using PCR and sequencing. Subsequently, we examined the transcriptional response of the Landes goose cecum following infection with the isolated Eimeria strain. Molecular analysis showed that the isolated Eimeria strain was Eimeria stigmosa, which was named the E. stigmosa SX-01 strain. Transcriptomic profiling identified 3806 differentially expressed genes (DEGs), including 2238 genes with increased expression and 1568 genes with decreased expression. The results obtained from the quantitative reverse transcription PCR (qRT-PCR) analysis confirmed that the RNA sequencing (RNA-seq) data were reliable. According to pathway enrichment analysis for the obtained DEGs, 24 pathways were significantly affected following infection with the E. stigmosa SX-01 strain, such as cytokine–cytokine receptor interaction, intestinal immune network for IgA production, cell adhesion molecules, gap junction, arachidonic acid metabolism, alpha-Linolenic acid metabolism, retinol metabolism, and PPAR signaling pathway. These transcriptional alterations were observed in E. stigmosa-infected geese without obvious clinical signs, indicating that E. stigmosa infection may trigger a strong subclinical host response related to metabolism, immune and inflammatory responses, and intercellular junctional complex-associated processes. Collectively, these findings have implications for better understanding the E. stigmosa–goose interactions at the molecular level and provide a foundation for future functional and comparative studies to dissect the pathogenic mechanisms and molecular markers associated with disease resistance, which are expected to inform the design of effective control strategies. Full article

Alpha-gal syndrome (AGS) is a tick-induced, IgE-mediated hypersensitivity to the oligosaccharide galactose-α-1,3-galactose (α-gal), which is expressed on glycoproteins and glycolipids of non-primate mammals but absent in humans. Gastrointestinal (GI) symptoms dominate the clinical presentation in a substantial proportion of patients yet remain systematically under-recognized, frequently being attributed to irritable bowel syndrome (IBS), non-celiac gluten sensitivity (NCGS), or lactose intolerance. This narrative review synthesizes the current evidence on the epidemiology, GI and systemic phenotype, immunological mechanisms, diagnostic strategies, management approaches, quality-of-life burden, and multi-level public health interventions for AGS, and it identifies critical knowledge gaps as of 2026. We searched PubMed/MEDLINE, Embase, and Web of Science from database inception through 31 March 2026, and synthesized the evidence narratively in accordance with the Scale for the Assessment of Narrative Review Articles (SANRA). GI symptoms occur in 47–69% of patients with AGS, with abdominal pain (58%), diarrhea (42%), nausea (39%), and vomiting (31%) as the cardinal manifestations. A characteristic 2–6 h delay between the ingestion of mammalian-derived food and symptom onset—explained by the glycolipid–chylomicron delivery mechanism—drives diagnostic confusion with functional GI disorders. Among 295,400 tested individuals in the United States, 30.5% were α-gal IgE positive, and an estimated 96,000–450,000 Americans were affected between 2010 and 2022. Despite this burden, 42% of U.S. healthcare providers had never heard of AGS. Strict avoidance of mammalian meat improves symptoms in 53–86% of adherent patients, although the condition carries a meaningful risk of anaphylaxis even among GI-predominant presenters. AGS is a prevalent, frequently misdiagnosed, and clinically morbid condition whose GI phenotype lies squarely within the gastroenterologist’s domain. A coordinated response that integrates clinician education, institutional diagnostic algorithms, and national surveillance infrastructure is urgently needed. Full article

Background/Objectives: Pseudorabies virus (PRV) variant strains have caused widespread outbreaks in China since 2011, and currently available vaccines provide suboptimal protection. Glycoprotein D (gD), the principal target of virus-neutralizing antibodies, represents a promising antigen for subunit vaccine development. However, CHO cell-based production systems suitable for large-scale manufacturing remain insufficiently explored. This study aimed to develop a potentially scalable CHO cell-derived PRV gD subunit vaccine and evaluate its immunogenicity and protective efficacy in mice. Methods: A stable Chinese hamster ovary (CHO) suspension cell line secreting the extracellular domain of PRV gD was established through signal peptide optimization and stepwise serum-free adaptation. The recombinant gD protein was purified using Ni²⁺- Sepharose High-Performance affinity chromatography and subsequently formulated with MONTANIDE ISA 206 adjuvant. Immunogenicity and protective efficacy were assessed in BALB/c mice through serological analysis, neutralization assays, lethal challenge experiments, and quantitative PCR. Results: The gD subunit vaccine induced rapid seroconversion of gD-specific IgG antibodies as early as 7 days post immunization and exhibited a strong booster effect, maintaining high antibody levels. Neutralizing antibodies were first detected at 14 days and increased significantly after booster immunization, with titers markedly exceeding those induced by a commercial inactivated PRV vaccine at 42 days (p = 0.001). Following lethal challenge with 10⁴ TCID₅₀ of the highly virulent PRV-TJ variant strain, vaccinated mice achieved 100% survival without clinical signs. Viral genome copy numbers in the brain and spinal cord were reduced by approximately 3.3 to 4.4 log₁₀ relative to the PBS control group. Conclusions: The CHO cell-derived PRV gD subunit vaccine elicits robust humoral immune responses and provides complete protection against lethal PRV variant challenge in mice. These findings support its further evaluation in the natural swine host toward the development of a safe and scalable subunit vaccine for pseudorabies control. Full article

Foam rolling (FR) is widely used to acutely enhance range of motion, yet the influence of different application volumes on neuromuscular, structural, and biochemical responses remains unclear. This study investigated the acute effects of low- and high-volume hamstrings FR interventions. Fifty-seven healthy male participants were randomly assigned to a high-volume FR group (IG10; 10 min per posterior thigh), a low-volume FR group (IG2; 2 min per posterior thigh), or a control group (CG; 20 min rest). Pre- and post-intervention assessments included sit-and-reach (SAR) performance, shoulder circumduction (SC) (mobility), maximal voluntary isometric contraction (MVIC), biceps femoris muscle stiffness (MS), and creatine kinase (CK) levels. Linear mixed-effects models revealed significant Time effects for SAR performance and SC, as well as a Group effect for SC (p < 0.05), whereas no significant Group × Time interactions were observed for any outcome (all p > 0.05). Significant improvements in SC were observed in both intervention groups compared with the CG, whereas no differences were detected between the two intervention durations. In contrast, no differential effects were observed for MS, maximal strength, or CK concentrations between the intervention groups, indicating that extending the FR duration from 2 to 10 min did not provide additional acute benefits. Full article

Irisin is a myokine derived from fibronectin type III domain-containing protein 5 (FNDC5) and is involved in energy metabolism, muscle development, and oxidative regulation. Although irisin has been extensively studied in mammals, its potential application in poultry production remains unclear. Enhancing growth performance and physiological resilience is critical for male white-feathered broiler chickens under intensive production systems. This study investigated the effects of dietary irisin supplementation on growth performance and physiological responses in male white-feathered broiler chickens. A total of 180 broilers were randomly allocated to three treatments, with six replicate pens of ten birds per treatment: basal diet and basal diet supplemented with 5 and 10 mg/kg irisin for 42 days. At 42 days, one bird from each replicate pen was sampled for carcass, meat-quality, serum, immune, and microbiota analyses. Dietary irisin supplementation significantly increased final body weight and average daily gain compared with the control group. Feed conversion ratio decreased from 1.51 in the control group to 1.46 in the 5 and 10 mg/kg groups. Carcass evaluation showed higher slaughter yield and breast muscle yield in irisin-supplemented birds, and cooking loss was significantly reduced in both breast and thigh muscles. Serum superoxide dismutase (SOD) activity was elevated in irisin-treated groups. In addition, immunoglobulin Y (IgY) and immunoglobulin M (IgM) concentrations were significantly increased. No significant treatment effects were observed for total antioxidant capacity (T-AOC), catalase (CAT), malondialdehyde (MDA), inflammatory cytokines (IL-6, TNF-α), or immune organ indices (thymus, spleen and bursa of Fabricius). Gut microbiota analysis showed numerical differences in the relative abundance of several major bacterial taxa among treatments. In conclusion, dietary irisin supplementation was associated with improved growth performance and selected carcass, meat-quality, antioxidant, immunoglobulin, and cecal microbiota outcomes in male white-feathered broiler chickens, supporting further investigation of its potential as a functional feed additive in poultry nutrition. Full article

Copper sulfate (CuSO₄) is one of the most widely used chemotherapeutic agents in aquaculture and aquatic veterinary medicine because of its broad-spectrum antiparasitic, antifungal, and antimicrobial activities. However, repeated exposure may induce oxidative stress and impair hematological and immune functions, thereby compromising fish health. This study evaluated the effects of pre-exposure and post-exposure dietary ellagic acid (EA) supplementation on CuSO₄-induced hematological, immunological, and oxidative stress alterations in common carp (Cyprinus carpio). A total of 150 fish were randomly allocated to five experimental groups: Control, EA, CuSO₄, pre-exposure EA + CuSO₄, and post-exposure CuSO₄ + EA. Fish were fed a diet supplemented with 100 mg EA kg⁻¹ feed for 14 days either before or after repeated CuSO₄ exposure (1 mg L⁻¹, 30 min day⁻¹ for seven consecutive days). Hematological variables, innate immune responses, and oxidative stress biomarkers were subsequently evaluated. CuSO₄ exposure significantly decreased red blood cell (RBC) count, hemoglobin (Hb), hematocrit (Ht), phagocytic activity (PA), phagocytic index (PI), total plasma protein (TP), immunoglobulin M (IgM), bactericidal activity (BA), lysozyme (LYZ), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), and reduced glutathione (GSH), while significantly increasing mean corpuscular hemoglobin concentration (MCHC), white blood cell (WBC) count, respiratory burst activity (NBT), myeloperoxidase (MPO), and malondialdehyde (MDA) (p < 0.05). Dietary EA supplementation markedly alleviated these alterations by restoring hematological homeostasis, improving innate immune responses, reducing lipid peroxidation, and reinforcing antioxidant defense systems in the liver, kidney, spleen, and gill. Both pre-exposure and post-exposure EA supplementation were associated with improvements in the evaluated biomarkers under the experimental conditions of the present study. However, because the two supplementation strategies were not evaluated against a time-matched CuSO₄ recovery control group, the present study does not permit a direct comparison of their relative efficacy. These findings demonstrate that dietary EA was associated with improvements in hematological, immunological, and oxidative stress biomarkers following experimental CuSO₄ exposure, potentially through antioxidant and immunomodulatory mechanisms. Therefore, dietary EA may serve as a promising functional feed additive to support antioxidant and immune status during experimental CuSO₄ exposure in common carp. Further studies including pathogen challenge models are required before its use as an adjunct to CuSO₄ treatments can be recommended. Full article

Therapeutic antibodies have transformed the management of infectious diseases, autoimmune disorders, and cancer, yet most approved agents continue to rely on a limited range of IgG-based Fc scaffolds. Consequently, the broader therapeutic potential of antibody isotypes, subclasses, allotypes, and host Fc receptor (FcR) genetics remains incompletely integrated into antibody design and clinical development. Emerging evidence indicates that these determinants profoundly influence effector function, pharmacokinetics, tissue distribution, immunogenicity, and therapeutic efficacy. This review provides a comprehensive, translational perspective on how antibody isotype selection, IgG subclass biology, allotypic variation, Fcγ receptor (FcγR) and neonatal Fc receptor (FcRn) genetics, and Fc engineering collectively shape therapeutic outcomes. Distinct from previous reviews that examine these factors individually, we integrate their roles across infectious diseases, autoimmunity, and cancer to identify common principles governing Fc-dependent immunity and therapeutic response. We further describe the clinical implications of Fc-mediated mechanisms, Fc glycoengineering, FcRn-targeted therapies, systems serology, and emerging non-IgG antibody platforms, highlighting both established applications and unresolved challenges. By unifying structural immunology, Fc pharmacology, host genetics, and disease biology, this review advances the concept of precision Fc pharmacology, in which antibody scaffold selection and Fc optimization are tailored to specific disease contexts and patient immune profiles. This framework provides a roadmap for the rational development of next-generation antibody therapeutics with improved efficacy, safety, and clinical precision. Full article

Lactic acid bacteria exopolysaccharides (LAB EPS) have garnered significant interest owing to their beneficial biological properties and safety. This study aimed to screen LAB EPS with comprehensive biological activities and anti-allergic potential from four high-yield strains, isolate and characterize their homogeneous polysaccharide fractions, and preliminarily explore their anti-allergic mechanism. Through in vitro evaluation of antibacterial, hyaluronidase inhibitory, antioxidant and immunomodulatory activities, Lacticaseibacillus casei LZ9183 EPS (183 EPS) was identified as the optimal candidate with the most superior comprehensive performance. Further purification via DEAE-52 anion exchange chromatography and Sephadex G-100 gel filtration chromatography yielded two homogeneous polysaccharide fractions, LZEPS-1 and LZEPS-2. Structural characterization results showed that LZEPS-1 (28.73 kDa) was a neutral polysaccharide composed of rhamnose, galactose, glucose and mannose with a total sugar content of 94.39 ± 0.92%, while LZEPS-2 (95.58 kDa) was an acidic polysaccharide containing glucose, galactose, arabinose, mannose, xylose and glucuronic acid with 92.17 ± 1.22% total sugars and 1.72 ± 0.04% protein. Using the RBL-2H3 cell degranulation model, we demonstrated that 183 EPS, LZEPS-1 and LZEPS-2 effectively alleviated IgE-mediated allergic responses by inhibiting the release of β-hexosaminidase and histamine, and modulating the secretion of IL-4 and TNF-α to restore the Th1/Th2 balance. These results propose that LAB EPS could potentially be utilized as natural anti-allergic functional ingredients in the development of functional foods or dietary supplements. Full article

Wle vanillin is widely used as a flavoring agent in food products, its potential as a non-antibiotic feed additive for broilers remains unexplored. This study primarily investigated the effects of dietary supplementation of vanillin on antioxidant activity, anti-inflammatory response, immune function, and gut microbiota composition in broilers. One-day-old male broilers were randomly assigned to five groups: a basal diet group, a positive control group (basal diet + 100 mg/kg chlortetracycline (CTC)), and three vanillin-supplemented groups (0.1%, 0.2%, or 0.4%) for 42 days. Results showed that vanillin improved antioxidant capacity, with elevated serum superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity and reduced malondialdehyde (MDA) levels. Broilers receiving vanillin supplementation showed lower levels of pro-inflammatory cytokines (interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α)) and higher interleukin-10 (IL-10) expression compared with controls. Additionally, serum immunoglobulin A (IgA) and immunoglobulin M (IgM) levels were also greater in the vanillin group. It also enhanced intestinal health by increasing the duodenal villus height-to-crypt depth ratio, improving intestinal morphology, raising the Firmicutes-to-Bacteroidetes ratio, and promoting Lactobacillus proliferation compared with CTC. Notably, growth performance data were exploratory in nature; vanillin was associated with numerical improvements in average daily gain (ADG) and feed conversion (F/G) ratio. These preliminary findings suggest that vanillin requires further investigation as a potential feed additive. Full article

Gyrovirus homsa1 (GyH1) causes immunosuppression and multi-organ damage in young poultry. The VP1 capsid protein (VP1) is a key target for subunit vaccine development; however, recombinant VP1 alone elicits limited immunogenicity and requires an efficient delivery system. Here, we developed a liposomal formulation associated with the GyH1 VP1 protein (LNP-VP1) and evaluated its immunogenicity and preliminary safety in specific-pathogen-free chickens. The prepared LNP-VP1 had a mean particle size of 230.11 ± 5.95 nm, a polydispersity index of 0.204 ± 0.023, a zeta potential of −36.55 ± 0.99 mV, and an apparent encapsulation efficiency of 84.03% ± 2.10%. In addition, immunization of chicks with LNP-VP1 induced robust antigen-specific IgG responses and significantly enhanced the infiltration of CD4⁺ and CD8⁺ T cells in the spleen. Furthermore, cytokine analysis revealed upregulation of IFN-γ, IL-4, and IL-17 levels following vaccination. Importantly, no vaccine-associated histopathological changes were observed in major immune or metabolic organs after immunization. Overall, LNP-VP1 effectively elicited both humoral and cellular immune responses with a favorable safety profile, indicating its potential as a candidate vaccine against GyH1 and providing experimental evidence supporting lipid nanoparticles as a delivery platform for avian subunit vaccines. Full article