Experimental porcine astrovirus type 3-associated polioencephalomyelitis in swine

2021 ◽  
pp. 030098582110257
Author(s):  
Franco Matias Ferreyra ◽  
Paulo E. H. Arruda ◽  
Laura K. Bradner ◽  
Karen M. Harmon ◽  
Min Zhang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Natural Infection ◽  
Quantitative Polymerase Chain Reaction ◽  
Clinical Signs ◽  
Subsequent Development ◽  
Tissue Homogenate ◽  
Post Inoculation ◽  
Neuronal Necrosis ◽  
Porcine Astrovirus ◽  
Type 3

Porcine astrovirus type 3 (PoAstV3) is an emerging virus in the family Astroviridae that has been recently associated with polioencephalomyelitis/encephalitis. Herein, we describe the experimental oral and intravenous inoculation of an infectious central nervous system (CNS) tissue homogenate containing PoAstV3 to cesarean-derived, colostrum-deprived pigs, and the subsequent development of clinical signs, histologic lesions, specific humoral immune response, and detection of viral particles by electron microscopy (EM) and viral RNA by RT-qPCR (reverse transcriptase quantitative polymerase chain reaction) and in situ hybridization (ISH). IgG against a portion of the PoAstV3 ORF2 capsid was first detected at 7 days post-inoculation (DPI) in 2 of 4 inoculated animals and in all inoculated animals by 14 DPI. At 21 and 28 DPI, 2 of 4 inoculated animals developed ataxia, tetraparesis, and/or lateral recumbency. All inoculated animals had histologic lesions in the CNS including perivascular lymphoplasmacytic cuffs, multifocal areas of gliosis with neuronal necrosis, satellitosis, and radiculoneuritis, and PoAstV3 RNA as detected by RT-qPCR within multiple anatomic regions of the CNS. Consistent viral structures were within the soma of a spinal cord neuron in the single pig examined by EM. Of note, PoAstV3 was not only detected by ISH in neurons of the cerebrum and spinal cord but also neurons of the dorsal root ganglion and nerve roots consistent with viral dissemination via axonal transport. This is the first study reproducing CNS disease with a porcine astrovirus strain consistent with natural infection, suggesting that pigs may serve as an animal model to study the pathogenesis of neurotropic astroviruses.

scholarly journals Polioencephalomyelitis in Domestic Swine Associated With Porcine Astrovirus Type 3

2019 ◽  
Vol 57 (1) ◽  
pp. 82-89 ◽  
Author(s):  
Franco S. Matias Ferreyra ◽  
Laura K. Bradner ◽  
Eric R. Burrough ◽  
Vickie L. Cooper ◽  
Rachel J. Derscheid ◽  
...  
Keyword(s):  
Quantitative Polymerase Chain Reaction ◽  
Neurologic Disease ◽  
Viral Encephalomyelitis ◽  
Formalin Fixed Paraffin ◽  
Porcine Astrovirus ◽  
Formalin Fixed Paraffin Embedded ◽  
Type 3 ◽  
Domestic Swine ◽  
Formalin Fixed

In the past decade, different members of the genus Mamastrovirus have been associated with outbreaks of neurologic disease in humans, cattle, sheep, mink, and, most recently, porcine astrovirus 3 (PoAstV3) in swine. We performed a retrospective analysis of 50 cases of porcine neurologic disease of undetermined cause but with microscopic lesions compatible with a viral encephalomyelitis to better understand the role and pathogenesis of PoAstV3 infection. Nucleic acid was extracted from formalin-fixed paraffin-embedded (FFPE) tissue for reverse transcription quantitative polymerase chain reaction (RT-qPCR) testing for PoAstV3. In addition, 3 cases with confirmed PoAstV3-associated disease were assayed by RT-qPCR to investigate PoAstV3 tissue distribution. PoAstV3 was detected in central nervous system (CNS) tissue via RT-qPCR and in situ hybridization in 13 of 50 (26%) FFPE cases assayed. PoAstV3 was rarely detected in any tissues outside the CNS. Positive cases from the retrospective study included pigs in various production categories beginning in 2010, the earliest year samples were available. Based on these results, PoAstV3 appears to be a recurring putative cause of viral encephalomyelitis in swine that is rarely detected outside of the CNS at the time of clinical neurologic disease, unlike other common viral causes of neurologic disease in swine.

Pathogenicity and immune response against porcine circovirus type 3 infection in caesarean-derived, colostrum-deprived pigs

2020 ◽  
Author(s):  
Gun Temeeyasen ◽  
Shay Lierman ◽  
Bailey L. Arruda ◽  
Rodger Main ◽  
Fabio Vannucci ◽  
...  
Keyword(s):  
Cellular Response ◽  
Clinical Signs ◽  
Humoral Response ◽  
T Cell Response ◽  
Porcine Circovirus ◽  
Histological Evaluation ◽  
Tissue Homogenate ◽  
Post Inoculation ◽  
Viral Shedding

Recently, a novel PCV species (PCV3) has been detected in cases associated with sow mortality, lesions consistent with porcine dermatitis and nephropathy syndrome, reproductive failure and multisystemic inflammation. The pathogenesis and clinical significance of PCV3 is still unclear. In this study, we investigated the immunopathogenesis of PCV3 in CD/CD pigs. Four treatment groups, PCV3 (n=6), PCV3-KLH (n=6), control (n=3) and control-KLH (n=3), were included with PCV3-positive tissue homogenate (gc=3.38×1012 ml−1 and gc=1.04×1011 ml−1), confirmed by quantitative PCR (qPCR) and next-generation sequencing. Clinical signs, viremia, viral shedding, systemic cytokines, humoral (IgG) and T-cellular response were evaluated for 42 days. At necropsy, tissues were collected for histological evaluation and PCV3 detection by qPCR and in situ hybridization. No significant clinical signs were observed through the study. Viremia was detected in both PCV3-inoculated groups from 3 days post-inoculation (p.i.) until the end of the study. Nasal shedding was detected from 3 to 28 days p.i. and faecal shedding was transient. PCV3 induced an early (7 days p.i.) and sustained (42 days p.i.) IgG response. No significant T-cell response was observed. Histological evaluation demonstrated lesions consistent with multisystemic inflammation and perivasculitis. All tissues evaluated were positive by qPCR and virus replication was confirmed by positive in situ hybridization. This study demonstrated the potential role of PCV3 in subclinical infection, producing a mild, multisystemic inflammatory response, prolonged viremia detectable for 42 days p.i., presence of IgG humoral response and viral shedding in nasal secretions. More research is required to understand and elucidate potential co-factors necessary in the manifestation and severity of clinical disease.

scholarly journals Efficacy of Intravenous Liposomal Amphotericin B (AmBisome) against Coccidioidal Meningitis in Rabbits

2002 ◽  
Vol 46 (8) ◽  
pp. 2420-2426 ◽  
Author(s):  
Karl V. Clemons ◽  
Raymond A. Sobel ◽  
Paul L. Williams ◽  
Demosthenes Pappagianis ◽  
David A. Stevens
Keyword(s):  
Spinal Cord ◽  
Amphotericin B ◽  
Liposomal Amphotericin ◽  
White Blood Cells ◽  
Clinical Signs ◽  
Liposomal Amphotericin B ◽  
Coccidioides Immitis ◽  
Lower Protein ◽  
Motor Abnormalities ◽  
The Brain

ABSTRACT The efficacy of intravenously administered liposomal amphotericin B (AmBisome [AmBi]) for the treatment of experimental coccidioidal meningitis was compared with those of oral fluconazole (FLC) and intravenously administered conventional amphotericin B (AMB). Male New Zealand White rabbits were infected by intracisternal inoculation of arthroconidia of Coccidioides immitis. Starting 5 days postinfection, animals received one of the following: 5% dextrose water diluent; AMB given at 1 mg/kg of body weight; AmBi given at 7.5, 15, or 22.5 mg/kg intravenously three times per week for 3 weeks; or oral FLC given at 80 mg/kg for 19 days. One week after the cessation of therapy, all survivors were euthanatized, the numbers of CFU remaining in the spinal cord and brain were determined, and histological analyses were performed. All AmBi-, FLC-, or AMB-treated animals survived and had prolonged lengths of survival compared with those for the controls (P < 0.0001). Treated groups had significantly lower numbers of white blood cells and significantly lower protein concentrations in the cerebrospinal fluid compared with those for the controls (P < 0.01 to 0.0005) and had fewer clinical signs of infection (e.g., weight loss, elevated temperature, and neurological abnormalities including motor abnormalities). The mean histological scores for AmBi-treated rabbits were lower than those for FLC-treated and control rabbits (P < 0.016 and 0.0005, respectively); the scores for AMB-treated animals were lower than those for the controls (P < 0.0005) but were similar to those for FLC-treated rabbits. All regimens reduced the numbers of CFU in the brain and spinal cord compared with those for the controls (P ≤0.0005). AmBi-treated animals had 3- to 11-fold lower numbers of CFU than FLC-treated rabbits and 6- to 35-fold lower numbers of CFU than AmB-treated rabbits. Three of eight animals given 15 mg of AmBi per kg had no detectable infection in either tissue, whereas other doses of AmBi or FLC cleared either the brain or the spinal cord of infection in fewer rabbits. In addition, clearance of the infection from both tissues was achieved in none of the rabbits, and neither tissue was cleared of infection in AMB-treated animals. Overall, these data indicate that intravenously administered AmBi is superior to oral FLC or intravenous AMB and that FLC is better than AMB against experimental coccidioidal meningitis. These data indicate that AmBi may offer an improvement in the treatment of coccidioidal meningitis. Additional studies are warranted.

scholarly journals Changes of Dorsal Root Ganglion Volume in Dogs with Clinical Signs of Degenerative Myelopathy Detected by Water-Excitation Magnetic Resonance Imaging

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1702
Author(s):  
Eiji Naito ◽  
Kohei Nakata ◽  
Yukiko Nakano ◽  
Yuta Nozue ◽  
Shintaro Kimura ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Spinal Cord ◽  
Magnetic Resonance ◽  
Clinical Signs ◽  
Intervertebral Disc Herniation ◽  
Resonance Imaging ◽  
Diagnostic Potential ◽  
Water Excitation ◽  
Spinal Cord Segment ◽  
Degenerative Myelopathy

Canine degenerative myelopathy (DM) is a progressive and fatal neurodegenerative disease. However, a definitive diagnosis of DM can only be achieved by postmortem histopathological examination of the spinal cord. The purpose of this study was to investigate whether the volumetry of DRG using the ability of water-excitation magnetic resonance imaging (MRI) to visualize the DRG in dogs has premortem diagnostic value for DM. Eight dogs with DM, twenty-four dogs with intervertebral disc herniation (IVDH), and eight control dogs were scanned using a 3.0-tesla MRI system, and water-excitation images were obtained to visualize and measure the volume of DRG, normalized by body surface area. The normalized mean DRG volume between each spinal cord segment and mean volume of all DRG between T8 and L2 in the DM group was significantly lower than that in the control and the IVDH groups (P = 0.011, P = 0.002, respectively). There were no correlations within the normalized mean DRG volume between DM stage 1 and stage 4 (rs = 0.312, P = 0.128, respectively). In conclusion, DRG volumetry by the water-excitation MRI provides a non-invasive and quantitative assessment of neurodegeneration in DRG and may have diagnostic potential for DM.

scholarly journals What Makes a Successful Donor? Fecal Transplant from Anxious-Like Rats Does Not Prevent Spinal Cord Injury-Induced Dysbiosis

Biology ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 254
Author(s):  
Emma K. A. Schmidt ◽  
Pamela J. F. Raposo ◽  
Karen L. Madsen ◽  
Keith K. Fenrich ◽  
Gillian Kabarchuk ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Mental State ◽  
Subsequent Development ◽  
Fecal Transplant ◽  
Cord Injury ◽  
Prevalence Of Depression ◽  
Inflammatory State ◽  
Motivation To Participate ◽  
Development Of Anxiety

Spinal cord injury (SCI) causes gut dysbiosis and an increased prevalence of depression and anxiety. Previous research showed a link between these two consequences of SCI by using a fecal transplant from healthy rats which prevented both SCI-induced microbiota changes and the subsequent development of anxiety-like behaviour. However, whether the physical and mental state of the donor are important factors in the efficacy of FMT therapy after SCI remains unknown. In the present study, rats received a fecal transplant following SCI from uninjured donors with increased baseline levels of anxiety-like behaviour and reduced proportion of Lactobacillus in their stool. This fecal transplant increased intestinal permeability, induced anxiety-like behaviour, and resulted in minor but long-term alterations in the inflammatory state of the recipients compared to vehicle controls. There was no significant effect of the fecal transplant on motor recovery in rehabilitative training, suggesting that anxiety-like behaviour did not affect the motivation to participate in rehabilitative therapy. The results of this study emphasize the importance of considering both the microbiota composition and the mental state of the donor for fecal transplants following spinal cord injury.

scholarly journals Experimental infection of broiler chicks with Salmonella Typhimurium from pigeon (Columba livia)

2016 ◽  
Vol 37 (4) ◽  
pp. 1919
Author(s):  
Átilla Holanda de Albuquerque ◽  
Régis Siqueira de Castro Teixeira ◽  
Débora Nishi Machado ◽  
Elisângela De Souza Lopes ◽  
Ruben Horn Vasconcelos ◽  
...  
Keyword(s):  
Salmonella Typhimurium ◽  
Clinical Signs ◽  
Columba Livia ◽  
Poultry Feed ◽  
Economic Losses ◽  
Control Group ◽  
Broiler Chicks ◽  
Post Inoculation ◽  
Microbiological Analysis ◽  
Fecal Samples

Several cases of animal and human salmonellosis caused by the Salmonella serotype Typhimurium have been reported. In animals, subclinical infection favors pathogen dissemination through feces. In this context, the domestic pigeon (Columba livia) with an asymptomatic condition may play an important role in the transmission of salmonellosis, through the elimination of contaminated feces in commercial aviaries or in poultry feed facilities, causing economic losses to the poultry industry and presenting a risk to public health. This study aimed to evaluate the mortality, clinical signs and the presence of Salmonella Typhimurium in the feces and organs of chicks previously inoculated with bacteria isolated from a pigeon. One-day-old chicks were distributed in two experimental groups (G1 and G2) of 32 birds each, and a control group of six birds. Two inocula of 0.4 and 0.7 mL with 105 and 106 colony forming units were used in G1 and G2 birds, respectively. At 1, 4, 7 and 14 days post-inoculation (dpi) fecal samples were pooled from each cage and individual cloacal swabs were collected. At 14 dpi, all chicks were euthanized and samples were collected from the liver, spleen, lung, cecum and intestine for microbiological analysis. Mortality was only observed among G2 birds (6.25%). Most birds presented clinical signs of diarrhea at 4 dpi and no symptom as observed at 14 dpi. The results from cloacal swabs demonstrated bacterial elimination in 68.8% and 53.1% of G2 and G1 birds, respectively at 1 dpi. Additionally, fecal samples had elevated bacterial shedding in all four periods of observation , with a higher excretion at 4 dpi (62.5%) for both groups. Among G2 birds, 74.2% were positive for the pathogen in the intestine; G1 birds presented the lowest rate of lung infection (29%), and both groups had more than 50% positivity for liver and caeca. The results revealed that infected chicks with a Salmonella Typhimurium strains isolated from pigeons may host the pathogen in several organs, and simultaneously present diarrheic disorders with significant levels of bacterial excretion in feces.

scholarly journals Evolution of the Seroprevalence of Pestivirus and Respiratory Viral Infections in Spanish Feedlot Lambs

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 160
Author(s):  
Teresa Navarro ◽  
Aurora Ortín ◽  
Oscar Cabezón ◽  
Marcelo De Las Heras ◽  
Delia Lacasta ◽  
...  
Keyword(s):  
Viral Infections ◽  
Clinical Signs ◽  
Production Performance ◽  
Herpesvirus Type ◽  
Bovine Herpesvirus Type 1 ◽  
Feedlot Lambs ◽  
Syncytial Virus ◽  
Type 3 ◽  
Bovine Parainfluenza Virus

The presence of respiratory viruses and pestiviruses in sheep has been widely demonstrated, and their ability to cause injury and predispose to respiratory processes have been proven experimentally. A longitudinal observational study was performed to determine the seroprevalence of bovine parainfluenza virus type 3 (BPIV-3), bovine respiratory syncytial virus (BRSV), bovine herpesvirus type 1 (BHV-1) and pestiviruses in 120 lambs at the beginning and the end of the fattening period. During this time, the animals were clinically monitored, their growth was recorded, and post-mortem examinations were performed in order to identify the presence of pneumonic lesions in the animals. Seroconversion to all viruses tested except BHV-1 was detected at the end of the period. Initially, BPIV-3 antibodies were the most frequently found, while the most common seroconversion through the analysed period occurred to BRSV. Only 10.8% of the lambs showed no detectable levels of antibodies against any of the tested viruses at the end of the survey. In addition, no statistical differences were found in the presentation of respiratory clinical signs, pneumonic lesions nor in the production performance between lambs that seroconverted and those which did not, except in the case of pestiviruses. The seroconversion to pestiviruses was associated with a reduction in the final weight of the lambs.

Clinical signs and histopathology of brain, spinal cord and muscle of the pelvic limb of rats experimentally infected with Trypanosoma evansi

2012 ◽  
Vol 208 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Aleksandro S. Da Silva ◽  
Camila B. Oliveira ◽  
Claudia M. Bertoncheli ◽  
Rosmarine P. Santos ◽  
Diego V. Beckmann ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Clinical Signs ◽  
Trypanosoma Evansi ◽  
Pelvic Limb

Histopathologic lesions in conventional pigs experimentally infected with Haemophilus parasuis serovar 5

2015 ◽  
Vol 43 (02) ◽  
pp. 91-96 ◽  
Author(s):  
R.-L. Austin-Busse ◽  
A. Ladinig ◽  
G. Balka ◽  
S. Zoels ◽  
M. Ritzmann ◽  
...  
Keyword(s):  
Clinical Signs ◽  
Control Group ◽  
Post Inoculation ◽  
Haemophilus Parasuis ◽  
Tissue Samples ◽  
Group A ◽  
Pathologic Lesions ◽  
Group B ◽  
Kidney Lesions ◽  
Challenge Group

Summary Objective: In the present study various tissues of pigs were investigated for the presence of histopathologic lesions after an experimental infection with Haemophilus (H.) parasuis serovar 5. Material and methods: Conventional pigs (n = 36) were divided into a control group B (n = 9) and a challenge group A (n = 27), which was infected intratracheally. Pigs that did not die prior to study termination were euthanized on day 14 post inoculation. Postmortem samples of the lung, heart, liver, kidney, spleen, left tarsal joint capsule and brain were collected. Results: All but one pig with detectable histopathologic lesions (n = 11) showed typical macroscopic changes. Histopatho logic examination of all tissue samples identified pyelitis (n = 10), synovitis (n = 7) and meningitis (n = 7) and all those animals were euthanized prior to study termination. No histopathologic lesions were found in pigs of the control group. The correlations between pyelitis and meningitis, pyelitis and synovitis and synovitis and meningitis were significant (p < 0.001). No significant correlation could be observed between the histopathologic and the clinical examination of the joints. The investigation of samples from the joints by PCR was not significantly correlated with the observed synovitis. The clinical observation of neurologic signs was significantly correlated with meningitis (p = 0.03). A significant correlation (p < 0.001) could be detected between meningitis and the detection of H. parasuis by PCR in brain samples. Conclusions: H. parasuis constantly causes clinical signs and pathologic lesions as soon as it infects the brain while it can infect the joints without causing histopathologic lesions. Pigs with histopathologic lesions do not always show typical clinical signs. Only few studies described the finding of kidney lesions in pigs with Glässer’s disease and this is the first study to describe a pyelitis in pigs experimentally infected with H. parasuis. The observed pyelitis mainly occurred in acute cases.

scholarly journals Pathogenicity of an African swine fever virus strain isolated in Vietnam and alternative diagnostic specimens for early detection of viral infection

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Hu Suk Lee ◽  
Vuong Nghia Bui ◽  
Duy Tung Dao ◽  
Ngoc Anh Bui ◽  
Thanh Duy Le ◽  
...  
Keyword(s):  
Early Detection ◽  
Oral Fluid ◽  
African Swine Fever Virus ◽  
Fluid Collection ◽  
Clinical Signs ◽  
African Swine Fever ◽  
Post Inoculation ◽  
Tissue Samples ◽  
Viral Loads ◽  
Specimen Collection

Abstract Background African swine fever (ASF), caused by the ASF virus (ASFV), was first reported in Vietnam in 2019 and spread rapidly thereafter. Better insights into ASFV characteristics and early detection by surveillance could help control its spread. However, the pathogenicity and methods for early detection of ASFV isolates from Vietnam have not been established. Therefore, we investigated the pathogenicity of ASFV and explored alternative sampling methods for early detection. Results Ten pigs were intramuscularly inoculated with an ASFV strain from Vietnam (titer, 103.5 HAD50/mL), and their temperature, clinical signs, and virus excretion patterns were recorded. In addition, herd and environmental samples were collected daily. The pigs died 5–8 days-post-inoculation (dpi), and the incubation period was 3.7 ± 0.5 dpi. ASFV genome was first detected in the blood (2.2 ± 0.8) and then in rectal (3.1 ± 0.7), nasal (3.2 ± 0.4), and oral (3.6 ± 0.7 dpi) swab samples. ASFV was detected in oral fluid samples collected using a chewed rope from 3 dpi. The liver showed the highest viral loads, and ear tissue also exhibited high viral loads among 11 tissues obtained from dead pigs. Overall, ASFV from Vietnam was classified as peracute to acute form. The rope-based oral fluid collection method could be useful for early ASFV detection and allows successful ASF surveillance in large pig farms. Furthermore, ear tissue samples might be a simple alternative specimen for diagnosing ASF infection in dead pigs. Conclusions Our data provide valuable insights into the characteristics of a typical ASFV strain isolated in Vietnam and suggest an alternative, non-invasive specimen collection strategy for early detection.

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