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Feather damaging behavior (feather picking) is a common malady of captive parrots. Diagnosis is challenging as a primary disadvantage to clinicians faced with diagnosis of parrot skin disease remains the lack of normative data for the healthy parrot epidermal microbiology. The objective of this pilot study was to establish bacterial and fungal cutaneous microbiota baselines for quaker parrots with and without feather loss. Healthy quaker parrots (Myiopsitta monachus n = 12) with intact feathers were compared to 12 quaker parrots with evidence of feather loss via next-generation DNA sequencing of bacteria and fungus swabbed from skin. Of 351 bacterial and 97 fungal species identified, no statistical differences occurred in bacteria or fungal alpha-diversity or beta-diversity based on age, sex, or feather loss. However, enclosure affected bacterial beta-diversity. The most abundant bacterial species for fully feathered quaker parrots were Exiguobacterium indicum, Sphingomonas yabuuchiae , and Corynebacterium spp.,. Fragaria/Populus euphratica, S. yabuuchiae, and E. indicum for quaker parrots with feather loss. Lactobacillales, Acinetobacter, Kocuria sp., and Streptococcus epidermidis were significantly enriched in fully feathered quaker parrots, while Streptococcaceae, Methylobacterium, Clostridiales, Nocardioidaceae, Nesterenkonia, and Actinomycetospora were significantly enriched in quaker parrots with feather loss. Both groups had Cladosporium halotolerans/sphaerospermum as the predominant fungus, while Capnodiales was significantly enriched in quaker parrots with feather loss. Use of next generation microbial sequencing as a preliminary diagnostic tool of bacterial and fungal communities of captive birds allows veterinarians to confirm cytologic diagnoses and circumvent the limitations of culture testing. Diagnostic implications include the potential transmission of pathogenic bacteria and/or fungi and pathogen resistance between cohoused birds. [ABSTRACT FROM AUTHOR]

Abstract: This study was designed to investigate the effectiveness of meloxicam in the treatment of proventricular dilatation disease induced by challenge with avian bornavirus (ABV), strain M24. Three groups of 4 cockatiels were employed. Group 1 was challenged with ABV alone, group 2 was challenged with ABV and 20 days later began daily oral meloxicam treatment, and group 3 received daily oral meloxicam alone. All birds in groups 1 and 3 remained in apparent good health and maintained their weight until being euthanized on day 150 after challenge (group 1) or day 130 of treatment (group 3). In contrast, group 2 birds died or were euthanized on or before day 98 because of severe weight loss and depression. Necropsy and histopathology results indicated that all birds in group 2 had pathologic evidence of proventricular dilatation disease. ABV was detected by reverse transcriptase polymerase chain reaction testing in all the major organs of the group 2 birds. The proventriculus was enlarged in 2 birds in group 1, and 75% of the birds in this group had ABV detectable in all their major organs. No significant lesions were observed in group 3 birds. [Copyright &y& Elsevier]

Background: Biolistic injections provide a needle-free delivery of antigen-laden microparticles to the epithelium. The precision of the injection preferentially targets the Langerhans cell network, which, although ideal for vaccination, might not be suitable for the downregulation of immune responses in immunotherapy. Objective: We sought to determine the ability of biolistic injection of antigen into the epithelium of sensitized mice to inhibit IgE antibody and lung inflammatory responses produced by further exposure to antigen. Methods: Mice were sensitized by means of a needle injection of ovalbumin (OVA) in alum and given a series of biolistic injections of OVA or vehicle control, followed by a boost of OVA in alum. Serum IgE and IgG antibodies were measured before and after the boost. The mice were then challenged intranasally, and the infiltration of inflammatory cells was measured by means of bronchoalveolar lavage. Airway reactivity of the challenged mice was measured by examining responses to methacholine with forced oscillatory techniques. Results: Biolistic injection of OVA into the dorsal skin of sensitized mice markedly inhibited IgE and IgG1 antibody responses induced by boosting. IgG2a antibody responses were reduced rather than stimulated. The eosinophilic inflammation in the bronchoalveolar lavage fluid induced by intranasal challenge was also markedly inhibited. Lung hyperreactivity showed an initial increase and then a decrease of responsiveness to methacholine, with elastance returning to the level of unsensitized mice. Biolistic injection into the buccal epithelium was also inhibitory. Conclusions: Biolistic injection of allergen inhibited the boosting of IgE antibody and eosinophilic lung inflammatory responses without inducing TH1 immunity. [Copyright &y& Elsevier]

Mice are commonly used to model human lung diseases. However, their small size poses substantial problems for accurately measuring lung function. Non-invasive techniques have been widely used but have severe limitations and should be restricted to screening for the presence of disease. Accurate measures of lung function and assessment of the site of disease pathology and drug action are possible using invasive techniques. Investigators must understand the strengths and weaknesses of each technique before deciding which to use. [Copyright &y& Elsevier]

Highlights: [•] Oral HBsAg boosting induces strong mucosal responses whereas parenteral Recombivax® boosting does not. [•] SFE-treated wafers enhance the immune response over full fat or hexane-treated wafers. [•] SFE treatment of maize favors HBsAg dimer formation. [•] Two boosting doses of oral or parenteral vaccine produce comparable responses. [•] Oral HBsAg boosting does not require an adjuvant for a robust response. [ABSTRACT FROM AUTHOR]

Typhoid fever remains a serious public health problem with a high impact on toddlers and young children. Vaccines against the Vi capsular polysaccharide are efficacious against typhoid fever demonstrating that antibodies against Vi confer protection. The currently licensed Vi typhoid vaccines have however limited efficacy and are manufactured by a complex process from wild-type bacteria. Due to these inherent issues with the current vaccines, an alternative vaccine based on an O-acetylated high molecular weight (HMW) polygalacturonic acid (GelSite-OAc™) was generated. The HMW polygalacturonic acid shares the same backbone as the Vi polysaccharide of Salmonella Typhi. The GelSite-OAc™ has a high molecular weight (>1 × 10 6  Da) and a high degree of O-acetylation (DOAc) (>5 μmole/mg), both exceeding the potency specifications of the current Vi vaccine. Studies in Balb/c mice demonstrated that GelSite-OAc™ was highly immunogenic, inducing a strong antigen-specific antibody response in a DOAc- and dose-dependent manner which was comparable to or higher than those induced by the licensed Vi vaccine. Importantly, the GelSite-OAc™ was shown to be fully protective in mice against lethal challenge with Salmonella Typhi. Furthermore, the GelSite-OAc™ demonstrated a boosting effect or memory response, exhibiting a >2-fold increase in antibody levels upon the second immunization with either GelSite-OAc™ or the Vi vaccine. This novel boosting effect is unique among polysaccharide antigens and potentially makes GelSite-OAc™ effective in people under 2 years old. Together these results suggest that the GelSite-OAc™ could be a highly effective vaccine against Salmonella Typhi. [ABSTRACT FROM AUTHOR]

Background The hepatitis B surface antigen (HBsAg) has been administered over the last 20 years as a parenteral vaccine against the hepatitis B virus (HBV). Despite high seroconversion rates, chronic infection rates are still high worldwide. Orally delivered vaccines provide a practical alternative to injected vaccines, potentially helping poorly responding populations and providing a viable alternative for populations in remote locations. Anamnestic responses are vital to establishing the efficacy of a given vaccine and have been assessed in this study using a plant-based oral delivery platform expressing HBsAg. Methods Long-term immunological memory was assessed in mice injected with a primary dose of Recombivax ® and boosted with orally-delivered HBsAg wafers, control wafers, or parenterally-delivered commercial vaccine (Recombivax ® ). Results Mice boosted with HBsAg orally-administered wafers displayed sharp increases in mucosal IgA titers in fecal material and steep increases in serum IgA, whereas mice boosted with Recombivax ® showed no detectable levels of IgA in either fecal or serum samples following four boosting treatments. Long-term memory in the orally-treated mice was evidenced by sustained fecal IgA, and serum IgA, IgG, and mIU/mL over one year, while Recombivax ® -treated mice displayed sustained serum IgG and mIU/mL. Furthermore, sharp increases in these same antibodies were induced after re-boosting at 47 and 50 weeks post-primary injection. Conclusions Orally-delivered vaccines can provide long-term immune responses mucosally and systemically. For sexually-transmitted diseases that can be acquired at mucosal surfaces, such as HBV, an oral delivery platform may provide added protection over a conventional parenterally administered vaccine. [ABSTRACT FROM AUTHOR]

Abstract: Hepatitis B remains a major global health problem despite the availability of a safe and effective vaccine. Segments of the population lack access to or respond poorly to the parenteral vaccine, perpetuating the infection-transmission cycle. A low cost, orally delivered vaccine has the potential to alleviate many of these problems. Here we describe the expression of a bioencapsulated hepatitis B surface antigen (HBsAg) in maize and its immunogenicity, demonstrating for the first time a commercially feasible oral subunit vaccine production system for a major disease. This work surmounts previous barriers to plant-produced vaccines by expressing HBsAg at much higher levels and retaining antigen immunogenicity post-processing: factors which facilitated a robust immune response in mice without the need for an adjuvant. This method provides a practical solution to the delivery of a low-cost, stable oral vaccine. [Copyright &y& Elsevier]

Abstract: The study aim was to establish how recruitment maneuvers (RMs) influence lung mechanics and to determine whether RMs produce lung injury. Healthy BALB/c mice were allocated to receive positive end-expiratory pressure (PEEP) at 2 or 6cmH2O and volume- (20 or 40mL/kg) or pressure-controlled (25cmH2O) RMs every 5 or 75min for 150min. The low-frequency forced oscillation technique was used to measure respiratory input impedance. Large RMs resulting in peak airway opening pressures (P ao)>30cmH2O did not increase inflammatory response or affect transcutaneous oxygen saturation but significantly lowered airway resistance, tissue damping and tissue elastance; the latter changes are likely associated with the bimodal pressure–volume behavior observed in mice. PEEP increase alone and application of RMs producing peak P ao below 25cmH2O did not prevent or reverse changes in lung mechanics; whereas frequent application of substantial RMs on top of elevated PEEP levels produced stable lung mechanics without signs of lung injury. [Copyright &y& Elsevier]

The use of recombinant gene technologies by the vaccine industry has revolutionized the way antigens are generated, and has provided safer, more effective means of protecting animals and humans against bacterial and viral pathogens. Viral and bacterial antigens for recombinant subunit vaccines have been produced in a variety of organisms. Transgenic plants are now recognized as legitimate sources for these proteins, especially in the developing area of oral vaccines, because antigens have been shown to be correctly processed in plants into forms that elicit immune responses when fed to animals or humans. Antigens expressed in maize (Zea mays) are particularly attractive since they can be deposited in the natural storage vessel, the corn seed, and can be conveniently delivered to any organism that consumes grain. We have previously demonstrated high level expression of the B-subunit of Escherichia coli heat-labile enterotoxin and the spike protein of swine transmissible gastroenteritis in corn, and have demonstrated that these antigens delivered in the seed elicit protective immune responses. Here we provide additional data to support the potency, efficacy, and stability of recombinant subunit vaccines delivered in maize seed. [Copyright &y& Elsevier]