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ObjectivesTo evaluate the association between plasma metabolites, biochemical analytes, diagnostic imaging findings, and the histologic diagnosis of hepatic lipidosis in bearded dragons. To assess the effects of gemfibrozil therapy on hepatic lipid accumulation and associated diagnostic tests.AnimalsFourteen bearded dragons (Pogona vitticeps) with varying severity of hepatic lipid accumulation (with and without hepatic lipidosis) were included.ProceduresAnimals underwent coelomic ultrasound, computed tomography (CT) scans, and coelioscopic hepatic biopsies. Clinical pathology tests included lipidologic tests, hepatic biomarkers, and mass spectrometry-based metabolomics. Animals were medicated with gemfibrozil 6mg/kg orally once a day for 2 months in a randomized blinded clinical trial prior to repeating previous diagnostic testing.ResultsHounsfield units on CT were negatively associated with increased hepatic vacuolation, while ultrasound and gross evaluation of the liver were not reliable. Beta-hydroxybutyric-acid (BHBA) concentrations were significantly associated with hepatic lipidosis. Metabolomics and lipidomics data found BHBA and succinic acid to be potential biomarkers for diagnosing hepatic lipidosis in bearded dragons. Succinic acid concentrations were significantly lower in the gemfibrozil treatment group. There was a tendency for improvement in the biomarkers and reduced hepatic fat in bearded dragons with hepatic lipidosis when treated with gemfibrozil, though the improvement was not statistically significant.ConclusionsThese findings provide information on the antemortem assessment of hepatic lipidosis in bearded dragons and paves the way for further research in diagnosis and treatment of this disease.

The emergence and re-emergence of pathogens with pandemic potential has been a persistent issue throughout history. Recent decades have seen significant outbreaks of zoonotic viruses from members of the Coronaviridae, Filoviridae, Paramyxoviridae, Flaviviridae, and Togaviridae families, resulting in widespread infections. The continual emergence of zoonotic viral pathogens and associated infections highlights the need for prevention strategies and effective treatments. Central to this effort is the availability of suitable animal models, which are essential for understanding pathogenesis and assessing transmission dynamics. These animals are also critical for evaluating the safety and efficacy of novel vaccines or therapeutics and are essential in facilitating regulatory approval of new products. Rapid development of animal models is an integral aspect of pandemic response and preparedness; however, their establishment is fraught by several rate-limiting steps, including selection of a suitable species, the logistical challenges associated with sharing and disseminating transgenic animals (e.g., the time-intensive nature of breeding and maintaining colonies), the availability of technical expertise, as well as ethical and regulatory approvals. A method for the rapid development of relevant animal models that has recently gained traction, in large part due to the COVID-19 pandemic, is the use of gene therapy vectors to express human viral receptors in readily accessible laboratory animals to enable virus infection and development of clinical disease. These models can be developed rapidly on any genetic background, making mechanistic studies and accelerated evaluation of novel countermeasures possible. In this review, we will discuss important considerations for the effective development of animal models using viral vector approaches and review the current vector-based animal models for studying viral pathogenesis and evaluating prophylactic and therapeutic strategies, with an emphasis on models of SARS-CoV-2 infection based on the vectorized expression of human angiotensin-converting enzyme 2.

Abstract Aquatic bird bornavirus 1 (ABBV-1) is a neurotropic virus that causes persistent infection in the nervous system of wild waterfowl. This study evaluated whether Pekin ducks, the most common waterfowl raised worldwide, are susceptible to ABBV-1 infection and associated disease. Groups of Pekin ducks were inoculated with ABBV-1 through the intracranial (IC; n, 32), intramuscular (IM; n, 30), and choanal (CH; n, 30) routes. Controls (CO; n, 29) received carrier only. At 1, 12, and 21 weeks postinfection (wpi), 7–14 birds were euthanized to assess virus distribution and lesions. Infection rates in the IC and IM groups were over 70%, while only 4 ducks in the CH group became infected. Neurological signs were observed in 8 ducks only, while over 25% of IC and IM birds had encephalitis and/or myelitis. Seroconversion was highest in the IC and IM groups, and mucosal ABBV-1 RNA shedding was most frequent in the IC group (53%). None of the fertile eggs laid during the experiment tested positive for ABBV-1 RNA. This study shows that Pekin ducks are permissive to ABBV-1 infection and partly susceptible to associated disease. While mucosal shedding may be an important route of transmission, congenital infection appears unlikely.

In psittacine birds, round cell neoplasms that originate from lymphocytes, plasma cells, histiocytes, or mast cells are sporadic and poorly described. The lack of morphological and immunohistochemical diagnostic criteria or grading schemes make specific diagnoses and prognoses challenging. We assessed cases of psittacine birds diagnosed with round cell neoplasia from 3 North American veterinary diagnostic laboratories to describe the diagnostic features of these tumors. For all cases, demographic data, anatomic distribution, histological features, and immunoreactivity for T (CD3) and B (Pax5 and MUM-1) cell markers were assessed using tissue microarrays and whole slide mounts. Thirty-eight psittacine birds representing 14 species were included. Tumors were mainly infiltrative and multicentric, were composed of homogenous sheets of round to polygonal cells, and commonly presented with a high mitotic count (average 21 mitoses per high-power field). Based on Pax5 immunoreactivity, B-cell lymphoma was most common (19/38 [50%]), and was significantly associated with involvement of the gastrointestinal and urogenital systems. Of the 38 cases, 6 (16%) were consistent with T-cell lymphoma, 3 (8%) with plasma cell tumor, and 3 (8%) were double-reactive for both B- and T-lymphocyte markers. This is the first study to describe morphologic and immunohistochemical features of round cell neoplasia in a large number of psittacine birds, and provides benchmark data for future studies aimed at elucidating the diagnosis and prognosis of these neoplasms. These data also provide useful information about reactivity of commercially available antibodies as lymphocyte markers in tissues of multiple psittacine species.

A 34-year-old female greater sulfur-crested cockatoo (Cacatua galerita galerita) was referred for suspected left globe rupture. Ophthalmic examination revealed effacement of the anterior chamber and cornea by a large mass. The left eye was enucleated due to suspicion of globe rupture, secondary to a neoplastic process or chronic trauma. Histopathological examination revealed complete effacement of the internal ocular structures by a neoplasm morphologically consistent with an iridociliary adenoma. The diagnosis was confirmed by Periodic acid-Schiff histochemistry and immunohistochemistry for S100, Melan-A/PNL2, and vimentin antigens. The cockatoo recovered well from surgery, with appropriate healing of the enucleation site, and no evidence of recurrence at 1-year follow-up. Key clinical message: To the authors' knowledge, this is the first report of iridociliary adenoma in a greater sulfur-crested cockatoo, and the third report of such a neoplasm in a psittacine species with a description of the use of immunohistochemistry to confirm a diagnosis of a rare tumor in a bird species.

Technologies and applications developed to assist and promote museum activities and cultural exhibitions have evolved significantly during the last decade, as has been proven by many works published in the scientific literature. This paper addresses a study developed with the specific purpose of understanding the possible knowledge-transfer outcomes of a digitization process meant to replicate original drawings by Leonardo da Vinci in the digital domain, allowing museums’ visitors to explore them as if they were manipulating the original artworks through custom interactive artifacts. A report is presented here to evaluate and investigate the didactic effectiveness of the fruition devices set up during a real exhibition, with a focus on the application dedicated to the drawing Study for the Adoration of the Magi, part of five artworks by Leonardo selected for exhibition during the reported event. The results encourage the adoption of this kind of technology for disseminating information at different levels, especially when knowledge contents are successfully explicated through proper didactic mediators.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged following an outbreak of unexplained viral illness in China in late 2019. Since then, it has spread globally causing a pandemic that has resulted in millions of deaths and has had enormous economic and social consequences. The emergence of SARS-CoV-2 saw the rapid and widespread development of a number of vaccine candidates worldwide, and this never-before-seen pace of vaccine development led to several candidates progressing immediately through clinical trials. Many countries have now approved vaccines for emergency use, with large-scale vaccination programs ongoing. Despite these successes, there remains a need for ongoing pre-clinical and clinical development of vaccine candidates against SARS-CoV-2, as well as vaccines that can elicit strong mucosal immune responses. Here, we report on the efficacy of a Newcastle disease virus-vectored vaccine candidate expressing SARS-CoV-2 spike protein (NDV-FLS) administered to cynomolgus macaques. Macaques given two doses of the vaccine via respiratory immunization developed robust immune responses and had reduced viral RNA levels in nasal swabs and in the lower airway. Our data indicate that NDV-FLS administered mucosally provides significant protection against SARS-CoV-2 infection, resulting in reduced viral burden and disease manifestation, and should be considered as a viable candidate for clinical development.

Aves polyomavirus 1, psittacine beak and feather disease virus, and psittacid herpesvirus 1 are important pathogens of psittacine birds with the potential to cause substantial morbidity and mortality. Using publically available nucleotide sequences, we developed and validated a triplex real-time PCR (rtPCR) assay to rapidly detect these 3 viruses. The assay had high analytical sensitivity, detecting

Abstract Aquatic bird bornavirus (ABBV-1), an avian bornavirus, has been reported in wild waterfowl from North America and Europe that presented with neurological signs and inflammation of the central and peripheral nervous systems. The potential of ABBV-1to infect and cause lesions in commercial waterfowl species is unknown. The aim of this study was to determine the ability of ABBV-1 to infect and cause disease in day-old Muscovy ducks (n = 174), selected as a representative domestic waterfowl. Ducklings became infected with ABBV-1 through both intracranial and intramuscular, but not oral, infection routes. Upon intramuscular infection, the virus spread centripetally to the central nervous system (brain and spinal cord), while intracranial infection led to virus spread to the spinal cord, kidneys, proventriculus, and gonads (centrifugal spread). Infected birds developed both encephalitis and myelitis by 4 weeks post infection (wpi), which progressively subsided by 8 and 12 wpi. Despite development of microscopic lesions, clinical signs were not observed. Only five birds had choanal and/or cloacal swabs positive for ABBV-1, suggesting a low potential of Muscovy ducks to shed the virus. This is the first study to document the pathogenesis of ABBV-1 in poultry species, and confirms the ability of ABBV-1 to infect commercial waterfowl.

From 2014–2023, infectious bronchitis virus (IBV) was detected in 6,589 samples from Canada, and partial nucleotide (nt) sequences of the IBV spike protein (S) gene were determined for 1,678 samples. Based on their S gene nt sequence identities and origin, Canadian IBVs could be classified into 4 groups: 1) 50.3% were variant viruses related to strains described in the United States; 2) 45.6% were vaccine-like viruses; 3) 2.1% were Eurasian viruses; 4) 2.0% were Canadian variants. Outbreaks with IBVs related to strains CAL1734/04, 4/91, and DMV/1639/11 were often associated with more severe disease in all chicken commodity groups. With the emergence of numerous IBV strains, the severity of infection and number of affected flocks increased. Outbreaks with various IBV strains overlapped in their emergence, peaked, and regressed, but the introduction of DMV/1639/11 has resulted in a continuous field challenge since its first detection in 2015. [ABSTRACT FROM AUTHOR]

The emergence and re-emergence of pathogens with pandemic potential has been a persistent issue throughout history. Recent decades have seen significant outbreaks of zoonotic viruses from members of the Coronaviridae, Filoviridae, Paramyxoviridae, Flaviviridae, and Togaviridae families, resulting in widespread infections. The continual emergence of zoonotic viral pathogens and associated infections highlights the need for prevention strategies and effective treatments. Central to this effort is the availability of suitable animal models, which are essential for understanding pathogenesis and assessing transmission dynamics. These animals are also critical for evaluating the safety and efficacy of novel vaccines or therapeutics and are essential in facilitating regulatory approval of new products. Rapid development of animal models is an integral aspect of pandemic response and preparedness; however, their establishment is fraught by several rate-limiting steps, including selection of a suitable species, the logistical challenges associated with sharing and disseminating transgenic animals (e.g., the time-intensive nature of breeding and maintaining colonies), the availability of technical expertise, as well as ethical and regulatory approvals. A method for the rapid development of relevant animal models that has recently gained traction, in large part due to the COVID-19 pandemic, is the use of gene therapy vectors to express human viral receptors in readily accessible laboratory animals to enable virus infection and development of clinical disease. These models can be developed rapidly on any genetic background, making mechanistic studies and accelerated evaluation of novel countermeasures possible. In this review, we will discuss important considerations for the effective development of animal models using viral vector approaches and review the current vector-based animal models for studying viral pathogenesis and evaluating prophylactic and therapeutic strategies, with an emphasis on models of SARS-CoV-2 infection based on the vectorized expression of human angiotensin-converting enzyme 2. [ABSTRACT FROM AUTHOR]

Spaghetti meat (SM) and woody breast (WB) are breast muscle myopathies of broiler chickens, characterized by separation of myofibers and by fibrosis, respectively. This study sought to investigate the transcriptomic profiles of breast muscles affected by SM and WB. Targeted sampling was conducted on a flock to obtain 10 WB, 10 SM, and 10 Normal Pectoralis major muscle samples from 37-day-old male chickens. Total RNA was extracted, cDNA was used for pair-end sequencing, and differentially expressed genes (DEGs) were determined by a false discovery rate of 1.5-fold change. Principal component and heatmap cluster analyses showed that the SM and WB samples clustered together. No DEGs were observed between SM and WB fillets, while a total of 4018 and 2323 DEGs were found when comparing SM and WB, respectively, against Normal samples. In both the SM and WB samples, Gene Ontology terms associated with extracellular environment and immune response were enriched. The KEGG analysis showed enrichment of cytokine–cytokine receptor interaction and extracellular matrix–receptor interaction pathways in both myopathies. Although SM and WB are macroscopically different, the similar transcriptomic profiles suggest that these conditions may share a common pathogenesis. This is the first study to compare the transcriptomes of SM and WB, and it showed that, while both myopathies had profiles different from the normal breast muscle, SM and WB were similar, with comparable enriched metabolic pathways and processes despite presenting markedly different macroscopic features.

The effects of salt-sensitive alginate (“A”) and a two-component salt-tolerant alginate system (“B”) used at a 0.5% or 1.0% level were evaluated in normal breast (NB) chicken fillets and in spaghetti meat (SM) fillets. Minced raw and cooked SM samples showed higher cooking loss (p < 0.05) and lower penetration force compared to NB meat. Both alginate systems significantly raised the penetration force in raw samples and decreased cooking loss (p < 0.05). Adding 1% of “A” or 0.5% “B” to SM, without salt, resulted in a similar penetration force as the cooked NB meat, while 1% “B” with salt resulted in a higher penetration force. Excluding salt from SM samples while adding alginate “A” or “B” improved texture profiles, but not to the same level as using NB without additives. Overall, salt, together with alginate “B”, improved the texture of SM to that of normal meat without myopathy.

Objectives To evaluate the association between plasma metabolites, biochemical analytes, diagnostic imaging findings, and the histologic diagnosis of hepatic lipidosis in bearded dragons. To assess the effects of gemfibrozil therapy on hepatic lipid accumulation and associated diagnostic tests. Animals Fourteen bearded dragons (Pogona vitticeps) with varying severity of hepatic lipid accumulation (with and without hepatic lipidosis) were included. Procedures Animals underwent coelomic ultrasound, computed tomography (CT) scans, and coelioscopic hepatic biopsies. Clinical pathology tests included lipidologic tests, hepatic biomarkers, and mass spectrometry-based metabolomics. Animals were medicated with gemfibrozil 6mg/kg orally once a day for 2 months in a randomized blinded clinical trial prior to repeating previous diagnostic testing. Results Hounsfield units on CT were negatively associated with increased hepatic vacuolation, while ultrasound and gross evaluation of the liver were not reliable. Beta-hydroxybutyric-acid (BHBA) concentrations were significantly associated with hepatic lipidosis. Metabolomics and lipidomics data found BHBA and succinic acid to be potential biomarkers for diagnosing hepatic lipidosis in bearded dragons. Succinic acid concentrations were significantly lower in the gemfibrozil treatment group. There was a tendency for improvement in the biomarkers and reduced hepatic fat in bearded dragons with hepatic lipidosis when treated with gemfibrozil, though the improvement was not statistically significant. Conclusions These findings provide information on the antemortem assessment of hepatic lipidosis in bearded dragons and paves the way for further research in diagnosis and treatment of this disease.

Monoclonal antibodies (mAbs) are important treatment modalities for preventing and treating infectious diseases, especially for those lacking prophylactic vaccines or effective therapies. Recent advances in mAb gene cloning from naturally infected or immunized individuals has led to the development of highly potent human mAbs against a wide range of human and animal pathogens. While effective, the serum half-lives of mAbs are quite variable, with single administrations usually resulting in short-term protection, requiring repeated doses to maintain therapeutic concentrations for extended periods of time. Moreover, due to their limited time in circulation, mAb therapies are rarely given prophylactically; instead, they are generally administered therapeutically after the onset of symptoms, thus preventing mortality, but not morbidity. Adeno-associated virus (AAV) vectors have an established record of high-efficiency in vivo gene transfer in a variety of animal models and humans. When delivered to post-mitotic tissues such as skeletal muscle, brain, and heart, or to organs in which cells turn over slowly, such as the liver and lungs, AAV vector genomes assume the form of episomal concatemers that direct transgene expression, often for the lifetime of the cell. Based on these attributes, many research groups have explored AAV-vectored delivery of highly potent mAb genes as a strategy to enable long-term expression of therapeutic mAbs directly in vivo following intramuscular or intranasal administration. However, clinical trials in humans and studies in nonhuman primates (NHPs) indicate that while AAVs are a powerful and promising platform for vectored immunoprophylaxis (VIP), further optimization is needed to decrease anti-drug antibody (ADA) and anti-capsid antibody responses, ultimately leading to increased serum transgene expression levels and improved therapeutic efficacy. The following review will summarize the current landscape of AAV VIP in NHP models, with an emphasis on vector and transgene design as well as general delivery system optimization. In addition, major obstacles to AAV VIP, along with implications for clinical translation, will be discussed.

Aims of the studyThe study aims to identify the differences in brain activity between participants with anorexia nervosa and healthy control using visual stimulus conditions combined with the quantitative dense-array EEG recording analysis method called Brain Activation Sequences (BAS).Materials and methods23 participants with anorexia nervosa and 21 healthy controls were presented with visual stimuli, including the subject’s facial expressions and body images. The 128-channel EEG data were processed using BAS and displayed as activity in up to 66 brain regions. Subsequent cluster analysis was used to identify groups of participants exhibiting area-specific activation patterns.ResultsCluster analysis identified three distinct groups: one including all healthy controls (HC) and two consisting of all participants with anorexia (AN-I with 19 participants and AN-II with four participants). The AN-I and AN-II groups differed in their response to treatment. Comparisons of HC vs. AN confirmed the dominance of the right cerebral hemisphere in participants with anorexia nervosa in two of the three reported conditions. The facial expressions condition, specifically the facial reaction expressing disgust, indicates the existence of a social attentional bias toward faces, whereas emotions remained undetected in participants. High limbic activity, medial frontal gyrus involvement, low fusiform cortex activity, and milder visual cortex activity in healthy controls compared to participants indicate that the facial expression stimulus is perceived by healthy subjects primarily as an emotion, not as the face itself. In the body image condition, participants showed higher activity in the fusiform gyrus and right insula, indicating activation of the brain’s “fear network.”ConclusionThe study describes a specific pattern of brain activation in response to facial expression of disgust and body images that likely contributes to social-cognitive and behavioral impairments in anorexia. In addition, the substantial difference in the pattern of brain activation within the participants with AN and its association with treatment resistance deserves special attention because of its potential to develop a clinically useful prediction tool and identify potential targets for, for example, neuromodulatory treatments and/or individualized psychotherapy.

Reading is a fundamental activity for the development of linguistic comprehension. To the aim of investigating the relationship between reading practice and comprehension, a systematic review of the literature was conducted, taking into account empirical research studies. The totality of the studies found positive effects on comprehension. The results also revealed that this area of study is mostly focused on the primary school age group. Indeed, it is nearly always related to other aspects of language development but also to the promotion of a positive attitude towards reading, motivation, socialization, emotional skills and understanding of reality. Little heed seems to be paid to the optimal way of reading. The results suggest the need for a greater reflection on this practice and a more precise identification of how to implement reading aloud in order to identify concrete actions to support reading, both in scholastic and extra-scholastic contexts.

Aims of the study:Commonly used approach to illness assessment focuses on the patient's actual state supplemented by binary records of past events and conditions. This research project was designed to explain subjective experience in idiopathic hypersomnia (IH) patients influenced by their clinical symptoms and comorbidities.Material and MethodsForty-three IH patients of both sexes (female 60.5%, male 39.5%) were assessed using a detailed structured examination. The interview covered neurologic, psychiatric, and internal medicine anamnesis, medication past and current, substance abuse, work impairment, detailed sleep-related data, specific sleep medication, and a full-length set of questionnaires including depression, quality of life, sleepiness, anxiety, fatigue, insomnia, and sleep inertia. The data were digitized and imported into statistical software (SPSS by IBM), and dynamic simulation software (Vensim by Ventana Systems Inc.) was used to build a causal loop diagram and stocks and flows diagram as a simulation structure.ResultsThe overall raw data and simulation-based patterns fit at 76.1%. The simulation results also identified the parameters that contribute the most to patients' subjective experience. These included sleep inertia, the refreshing potential of naps, the quality of nocturnal sleep, and the social aspects of the patient's life. Psychiatric disorders influence the overall pattern at a surprisingly low level. The influence of medication has been studied in detail. Although its contribution to the dynamics looks marginal at first sight, it significantly influences the contribution of other variables to the overall patient experience of the disease.ConclusionEven the simplified dynamic structure designed by the research team reflects the real-life events in patients with IH at the acceptable level of 76.1% and suggests that a similar structure plays an important role in the course of the disease. Therapeutic focus on the parameters identified by the model should enhance the patients' subjective experience throughout illness duration and might even turn the progress from negative into positive. Further research is needed to understand the dynamics of idiopathic hypersomnia in greater detail to better understand the causes and design therapeutic approaches to improve patients' quality of life.

In this study, we compared three popular textural tests: the compression, Meullenet–Owens razor blade (MORS), and Allo–Kramer (AK) tests, which are used to detect the wooden breast (WB) and spaghetti meat (SM) myopathies. A total of 209 fillets (71 WB, 71 SM, 67 normal) were selected from three different flocks at a large commercial plant. Thawed fillets were subjected to 20% compression tests before and after cooking, and cooked samples were subjected to the MORS and AK tests. The compression test on raw samples showed that normal and SM fillets had lower force (5.61 and 4.69 vs. 9.52 N), work (25 and 22 vs. 45 N mm), and Young’s modulus (2.71 and 2.11 vs. 4.29 N/s, p

Abstract Background Exercise training provides benefits for individuals with cystic fibrosis; however, the optimal program is unclear. High-intensity interval training is safe and effective for improving ‘functional capacity’ in these individuals with peak rate of O2 uptake typically referenced. The ability to adjust submaximal rate of oxygen uptake (V̇O2 kinetics) might be more important for everyday function because maximal efforts are usually not undertaken. Moreover, the ability of high-intensity training to accelerate V̇O2 kinetics for individuals with cystic fibrosis could be enhanced with O2 supplementation during training. Methods Nine individuals with cystic fibrosis completed incremental cycling to limit of tolerance followed by 8 weeks of high-intensity interval cycling (2 sessions per week x ~ 45 min per session) either with (n = 5; O2+) or without (AMB) oxygen supplementation (100%). Each session involved work intervals at 70% of peak work rate followed by 60 s of recovery at 35%. For progression, duration of work intervals was increased according to participant tolerance. Results Both groups experienced a significant increase in work-interval duration over the course of the intervention (O2+, 1736 ± 141 v. 700 ± 154 s; AMB, 1463 ± 598 v. 953 ± 253 s; P = 0.000); however, the increase experienced by O2+ was greater (P = 0.027). During low-intensity constant-work-rate cycling, the V̇O2 mean response time was shortened post compared to pre training (O2+, 34 ± 11 v. 44 ± 9 s; AMB, 39 ± 14 v. 45 ± 17 s; P = 0.000) while during high-intensity constant-work-rate cycling, time to exhaustion was increased (O2+, 1628 ± 163 v. 705 ± 133 s; AMB, 1073 ± 633 v. 690 ± 348 s; P = 0.002) and blood [lactate] response was decreased (O2+, 4.5 ± 0.9 v. 6.3 ± 1.4 mmol. L− 1; AMB, 4.5 ± 0.6 v. 5.2 ± 1.4 mmol. L− 1; P = 0.003). These positive adaptations were similar regardless of gas inspiration during training. Conclusion Eight weeks of high-intensity interval training for patients with cystic fibrosis accelerated V̇O2 kinetics and increased time to exhaustion. This provides some evidence that these patients may benefit from this type of exercise. Trial registration This study was retrospectively registered in the ISRTCN registry on 22/06/2019 (#ISRCTN13864650).

Spaghetti meat (SM), woody breast (WB), and white striping (WS) are myopathies that affect the pectoral muscle of fast-growing broiler chickens. The prevalence and possible risk factors of these myopathies have been reported in other countries, but not yet in Canada. Thus, the objective of this study was to assess the prevalence and risk factors associated with these myopathies in a representative population of Canadian broilers. From May 2019 to March 2020, 250 random breast fillets from each of 37 flocks (total, 9,250) were obtained from two processing plants and assessed for the presence and severity of myopathies. Demographic data (e.g., sex and average live weight), environmental conditions during the grow-out period (e.g., temperature), and husbandry parameters (e.g., vaccination) were collected for each flock. Associations between these factors and the myopathies were tested using logistic regression analyses. The prevalence of SM, severe WB, and mild or moderate WS was 36.3% (95% CI: 35.3-37.3), 11.8% (95% CI: 11.2-12.5), and 96.0% (95% CI: 95.6-96.4), respectively. Most (85.1%) of the fillets showed multiple myopathies. Regression analyses showed that the odds of SM increased with live weight (OR = 1.30, 95% CI 1.01-1.69) and higher environmental temperature during the grow-out period (OR = 1.75, 95% CI 1.31-2.34). The odds of WB increased with live weight (OR = 1.23, 95% CI 1.03-1.47) and when flocks were not vaccinated against coccidia (OR = 1.86, 95% CI 1.51-2.29). This study documents for the first time a high prevalence of myopathies in Ontario broilers, and suggests that these lesions may have a significant economic impact on the Canadian poultry industry. Our results indicate that environmental conditions and husbandry are associated with the development of breast myopathies, in agreement with the current literature. Future studies are needed to determine how risk factors can promote the occurrence of these conditions, in order to implement possible mitigating strategies.

Pseudomonas aeruginosa is a bacterial pathogen of global concern and is responsible for 10–15% of nosocomial infections worldwide. This opportunistic bacterial pathogen is known to cause serious complications in immunocompromised patients and is notably the leading cause of morbidity and mortality in patients suffering from cystic fibrosis. Currently, the only line of defense against P. aeruginosa infections is antibiotic treatment. Due to the acquired and adaptive resistance mechanisms of this pathogen, the prevalence of multidrug resistant P. aeruginosa strains has increased, presenting a major problem in healthcare settings. To date, there are no approved licensed vaccines to protect against P. aeruginosa infections, prompting the urgent need alternative treatment options. An alternative to traditional vaccines is vectored immunoprophylaxis (VIP), which utilizes a safe and effective adeno-associated virus (AAV) gene therapy vector to produce sustained levels of therapeutic monoclonal antibodies (mAbs) in vivo from a single intramuscular injection. In this review, we will provide an overview of P. aeruginosa biology and key mechanisms of pathogenesis, discuss current and emerging treatment strategies for P. aeruginosa infections and highlight AAV-VIP as a promising novel therapeutic platform.

Abstract Background Aquatic bird bornavirus 1 (ABBV-1) has been associated with neurological diseases in wild waterfowls. In Canada, presence of ABBV-1 was demonstrated by RT-qPCR and immunohistochemistry in tissues of waterfowls with history of neurological disease and inflammation of the central and peripheral nervous tissue, although causation has not been proven by pathogenesis experiments, yet. To date, in vitro characterization of ABBV-1 is limited to isolation in primary duck embryo fibroblasts. The objectives of this study were to describe isolation of ABBV-1 in primary duck embryonic fibroblasts (DEF), and characterize replication in DEF and three immortalized avian fibroblast cell lines (duck CCL-141, quail QT-35, chicken DF-1) in order to evaluate cellular permissivity and identify suitable cell lines for routine virus propagation. Methods The virus was sequenced, and phylogenetic analysis performed on a segment of the N gene coding region. Virus spread in cell cultures, viral RNA and protein production, and titres were evaluated at different passages using immunofluorescence, RT-qPCR, western blotting, and tissue culture dose 50% (TCID50) assay, respectively. Results The isolated ABBV-1 showed 97 and 99% identity to European ABBV-1 isolate AF-168 and North American ABBV-1 isolates 062-CQ and CG-N1489, and could infect and replicate in DEF, CCL-141, QT-35 and DF-1 cultures. Viral RNA was detected in all four cultures with highest levels observed in DEF and CCL-141, moderate in QT-35, and lowest in DF-1. N protein was detected in western blots from infected DEF, CCL-141 and QT-35 at moderate to high levels, but minimally in infected DF-1. Infectious titre was highest in DEF (between approximately 105 to 106 FFU / 106 cells). Regarding immortalized cell lines, CCL-141 showed the highest titre between approximately 104 to 105 FFU / 106 cells. DF-1 produced minimal infectious titre. Conclusions This study confirms the presence of ABBV-1 among waterfowl in Canada and reported additional in vitro characterization of this virus in different avian cell lines. ABBV-1 replicated to highest titre in DEF, followed by CCL-141 and QT-35, and poorly in DF-1. Our results showed that CCL-141 can be used instead of DEF for routine ABBV-1 production, if a lower titre is an acceptable trade-off for the simplicity of using immortalized cell line over primary culture.