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1.
Vet Res ; 55(1): 89, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39010163

RESUMEN

Since the reintroduction of African swine fever virus (ASFV) in Europe in 2007 and its subsequent spread to Asia, wild boar has played a crucial role in maintaining and disseminating the virus. There are significant gaps in the knowledge regarding infection dynamics and disease pathogenesis in domestic pigs and wild boar, particularly at the early infection stage. We aimed to compare domestic pigs and wild boar infected intranasally to mimic natural infection with one of the original highly virulent genotype II ASFV isolates (Armenia 2007). The study involved euthanising three domestic pigs and three wild boar on days 1, 2, 3, and 5 post-infection, while four domestic pigs and four wild boar were monitored until they reached a humane endpoint. The parameters assessed included clinical signs, macroscopic lesions, viremia levels, tissue viral load, and virus shedding in nasal and rectal swabs from day 1 post-infection. Compared with domestic pigs, wild boar were more susceptible to ASFV, with a shorter incubation period and earlier onset of clinical signs. While wild boar reached a humane endpoint earlier than domestic pigs did, the macroscopic lesions were comparatively less severe. In addition, wild boar had earlier viremia, and the virus was also detected earlier in tissues. The medial retropharyngeal lymph nodes were identified as key portals for ASFV infection in both subspecies. No viral genome was detected in nasal or rectal swabs until shortly before reaching the humane endpoint in both domestic pigs and wild boar, suggesting limited virus shedding in acute infections.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Genotipo , Sus scrofa , Animales , Virus de la Fiebre Porcina Africana/genética , Virus de la Fiebre Porcina Africana/fisiología , Fiebre Porcina Africana/virología , Porcinos , Esparcimiento de Virus , Viremia/veterinaria , Viremia/virología , Carga Viral/veterinaria , Virulencia
2.
J Vet Intern Med ; 38(4): 2373-2379, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38899610

RESUMEN

BACKGROUND: Equine parvovirus hepatitis (EqPV-H) can cause Theiler's disease and subclinical hepatitis in horses. OBJECTIVES: Assess the frequency of subclinical EqPV-H infection in hospitalized horses and to study viral transmission by investigating potential shedding routes. ANIMALS: One hundred sixteen equids, that presented to the University Equine Hospital of the University of Veterinary Medicine Vienna between February 2021 and March 2022, for causes other than hepatopathy. METHODS: In this cross-sectional study, samples (serum, feces, nasal, and buccal swabs) of hospitalized horses were collected. Sera were screened for the presence of anti-EqPV-H antibodies by a luciferase immunoprecipitation system assay. Quantitative PCR was used for the detection of EqPV-H DNA in the samples and a nested PCR was used for further validation. RESULTS: Seroprevalence was 10.3% (12/116) and viremia occurred in 12.9% (15/116) of the serologically positive horses. The detected viral load in serum varied from non-quantifiable amount to 1.3 × 106 genome equivalents per milliliter of serum. A low viral load of EqPV-H DNA was detected in 2 nasal swabs and 1 fecal sample. CONCLUSION AND CLINICAL IMPORTANCE: EqPV-H DNA was detected in nasal secretions and feces of viremic horses, which could pose a risk to naive hospitalized horses. It is advisable to screen hospitalized horses that are potential donors of blood or plasma to reduce the risk of iatrogenic EqPV-H transmission.


Asunto(s)
Hepatitis Viral Animal , Enfermedades de los Caballos , Infecciones por Parvoviridae , Parvovirus , Esparcimiento de Virus , Animales , Caballos , Enfermedades de los Caballos/virología , Enfermedades de los Caballos/epidemiología , Infecciones por Parvoviridae/veterinaria , Infecciones por Parvoviridae/virología , Infecciones por Parvoviridae/epidemiología , Austria/epidemiología , Estudios Transversales , Hepatitis Viral Animal/virología , Hepatitis Viral Animal/epidemiología , Masculino , Femenino , Parvovirus/aislamiento & purificación , Heces/virología , Anticuerpos Antivirales/sangre , Infecciones Asintomáticas/epidemiología , Estudios Seroepidemiológicos , Viremia/veterinaria , ADN Viral , Carga Viral/veterinaria
4.
Am J Vet Res ; 85(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38484465

RESUMEN

OBJECTIVE: To investigate the role of equine herpesvirus-2 (EHV-2) and equine herpesvirus-5 (EHV-5) in equine glandular gastric disease (EGGD) by visualizing and quantifying these gamma herpesviruses in EGGD-affected and normal glandular gastric mucosa of horses. A secondary objective was to describe the histopathological abnormalities in the equine gastric glandular mucosa in horses with EGGD. ANIMALS: 29 horses (n = 21 postmortem and 8 gastroscopy) categorized as normal (11), EGGD (12), or both EGGD and equine squamous gastric disease (6). METHODS: Glandular gastric mucosal samples were collected from horses by gastroscopy or postmortem. Histopathology and in situ hybridization targeting EHV-2 and EHV-5 were performed on grossly normal and abnormal glandular gastric mucosa. The number of in situ hybridization-positive cells per millimeter squared of tissue was calculated. Evaluators were blinded to groups. RESULTS: Glandular gastric tissues from horses without EGGD had higher viral loads in the mucosa than normal or abnormal tissues from EGGD horses. There was no difference in viral loads for EHV-2 or EHV-5 between grossly or endoscopically normal to abnormal gastric tissues within horses with EGGD. Lymphocytic plasmacytic gastritis was the most common histopathological abnormality, with only 3 horses having mucosal disruption (glandular ulcer or erosion). CLINICAL RELEVANCE: Equine gamma herpesviruses are unlikely to play a role in the pathophysiology of EGGD. EGGD is frequently inflammatory with occasional mucosal disruption (ulcer or erosion).


Asunto(s)
Infecciones por Herpesviridae , Enfermedades de los Caballos , Gastropatías , Carga Viral , Animales , Caballos , Enfermedades de los Caballos/virología , Enfermedades de los Caballos/patología , Infecciones por Herpesviridae/veterinaria , Infecciones por Herpesviridae/virología , Infecciones por Herpesviridae/patología , Carga Viral/veterinaria , Gastropatías/veterinaria , Gastropatías/virología , Gastropatías/patología , Femenino , Masculino , Mucosa Gástrica/virología , Mucosa Gástrica/patología , Gammaherpesvirinae/aislamiento & purificación , Hibridación in Situ/veterinaria
5.
Vet Res Commun ; 48(1): 191-202, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37610507

RESUMEN

Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leucosis (EBL), which affects cattle globally. In Egypt, BLV control strategies have been ignored because of the shortage of BLV research studies and the silent infection in most animals. This study aimed to identify the risk factors associated with the prevalence of BLV among dairy and beef cattle from six different geographic and climatic provinces in Egypt. Additionally, risk factors affecting the BLV proviral load (PVL) among the positive cattle were targeted. The total BLV prevalence in cattle from six investigated Egyptian provinces was 24.2% (105/433), while the mean PVL (8651.6 copies /105 white blood cells) was absolutely high as estimated by the BLV-CoCoMo-quantitative polymerase chain reaction (qPCR)-2 assay. Analysis of the influence of risk factors (age, sex, breed, production type, farm size, and location) on BLV prevalence indicated that the Holstein breed (OR = 1.582, p = 0.007), beef cattle (OR = 1.088, p = 0.0001), large-size farms (OR = 1.26, p = 0.0001), and cattle from Damietta (OR = 1.43, p = 0.0001) and Cairo (OR = 1.16, p = 0.0001) were ultimately proven the most important risks for BLV infection. The risk factors were analyzed considering the BLV PVL levels in the BLV-positive cases. Significantly high PVL (HPVL) levels were observed in cattle > 5 years old (p < 0.0001), females (p = 0.0008), Holstein (p < 0.0001), dairy cows (p = 0.0053), large-size farms (p < 0.0001), and cattle from Damietta (p < 0.0001) compared to other categories. Contrary, no significant differences in PVL levels were reported between the Native and Mixed cattle breeds (p = 0.13). Ultimately, the logistic regression model indicated that the probability of carrying HPVL in cattle > 5 years is 1.27 (95% CI: 1.03-2.09, p < 0.001) times more likely compared to cattle < 2 years old. In conclusion, the findings were valuably correlating the BLV prevalence with PVL as an indicator of the risk of BLV infection.


Asunto(s)
Enfermedades de los Bovinos , Leucosis Bovina Enzoótica , Virus de la Leucemia Bovina , Femenino , Bovinos , Animales , Provirus/genética , Carga Viral/veterinaria , Leucosis Bovina Enzoótica/epidemiología , Factores de Riesgo
6.
J Aquat Anim Health ; 36(1): 45-56, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38124451

RESUMEN

OBJECTIVE: The primary objective of this study was to determine the effects of temperature on viral erythrocytic necrosis (VEN) progression under controlled conditions. Secondarily, this study was intended to evaluate the combined effects of temperature and VEN on the Pacific Herring Clupea palasii transcriptome. METHODS: The effects of temperature on VEN progression were assessed by waterborne exposure of laboratory-reared, specific-pathogen-free Pacific Herring to tissues homogenates containing erythrocytic necrosis virus (ENV) at 6.9, 9.0, or 13.5°C. RESULT: Exposure of Pacific Herring to ENV resulted in the establishment of infections characterized by high infection prevalence (89%; 40/45) and mean viral loads (5.5 log10 [gene copies/µg genomic DNA]) in kidney tissues at 44 days postexposure. Mean viral loads were significantly higher in fish from the ambient (mean = 9.0°C) and warm (mean = 13.5°C) treatments (6.1-6.2 log10 [gene copies/total genomic DNA]) than in fish from the cool (mean = 6.9°C) treatment (4.3 log10 [gene copies/µg genomic DNA]). Similarly, the peak proportion of diseased fish was directly related to temperature, with cytoplasmic inclusion bodies detected in 21% of fish from the cool treatment, 52% of fish from the ambient treatment, and 60% of fish from the warm treatment. The mean VEN load in each fish (enumerated as the percentage of erythrocytes with cytoplasmic inclusions) at 44 days postexposure increased with temperature from 15% in the cool treatment to 36% in the ambient treatment and 32% in the warm treatment. Transcriptional analysis indicated that the number of differentially expressed genes among ENV-exposed Pacific Herring increased with temperature, time postexposure, and viral load. Correlation network analysis of transcriptomic data showed robust activation of interferon and viral immune responses in the hepatic tissue of infected individuals independent of other experimental variables. CONCLUSION: Results from this controlled laboratory study, combined with previous observations of natural epizootics in wild populations, support the conclusion that temperature is an important disease cofactor for VEN in Pacific Herring.


Asunto(s)
Enfermedades de los Peces , Animales , Enfermedades de los Peces/epidemiología , Temperatura , Carga Viral/veterinaria , Peces , Necrosis/veterinaria , Cuerpos de Inclusión , ADN , Eritrocitos , Inmunidad
7.
Res Vet Sci ; 159: 101-105, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37104992

RESUMEN

Bovine papillomavirus (BPV) types 1 and 2 are causally associated with equine sarcoid, the most common mesenchymal neoplasm of horses, but the viral load (VL) differs between lesions. Sensitive and accurate BPV detection and quantification is essential for clinicians to confirm clinical suspicion, as well as in research settings for stratifying these skin lesions. Due to the limitations of histopathology in sarcoid diagnosis, PCR screening of superficial swabs constitutes the principal sampling method for BPV detection. This study aimed to investigate the ability of superficial swabs and fine-needle aspirates (FNA) to accurately detect the VL in equine sarcoids, considering the main clinical types: occult, nodular, verrucous and fibroblastic. Superficial swabs and FNAs from a series of sarcoid-affected horses were tested in parallel for BPV DNA quantification. Quantitative real-time PCR screening of postoperative tissue biopsies served as reference standard for the accuracy assessment of the viral titters. Our results indicate that VL is not a predictor of the clinical type. Student's t-test results gave evidence of a significant difference between both sample methods (P < 0.001) with FNA giving the best approximation of the actual VL (P < 0.01). In contrast to superficial swabs, the reference standard correlated moderately with FNA in general (P < 0.05; r = 0.39) and strongly with FNA results within the occult sarcoid group (P < 0.05; r = 0.59). In conclusion, the correlation of FNA with the reference standard was strong enough to suggest this is the preferred method for quantifying VL in sarcoids.


Asunto(s)
Papillomavirus Bovino 1 , Enfermedades de los Caballos , Neoplasias , Infecciones por Papillomavirus , Sarcoidosis , Enfermedades de la Piel , Neoplasias Cutáneas , Caballos/genética , Animales , Carga Viral/veterinaria , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/veterinaria , ADN Viral/análisis , Enfermedades de la Piel/veterinaria , Neoplasias/veterinaria , Sarcoidosis/diagnóstico , Sarcoidosis/veterinaria , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Enfermedades de los Caballos/diagnóstico , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/veterinaria , Papillomavirus Bovino 1/genética
8.
J Vet Diagn Invest ; 35(3): 278-283, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36896657

RESUMEN

Columbid alphaherpesvirus 1 (CoHV1) is associated with oral or upper respiratory tract lesions, encephalitis, and occasional fatal systemic disease in naive or immunosuppressed pigeons. Clinical disease is often reported with CoHV1 and coinfecting viruses, including pigeon circovirus (PiCV), which may cause host immunosuppression and augment lesion development. A natural outbreak of CoHV1 and PiCV coinfection occurred in a flock of 60 racing rock pigeons (Columba livia), in which 4 pigeons succumbed within 7 d of clinical onset. Lesions included suppurative stomatitis, pharyngitis, cloacitis, meningitis, and tympanitis, with eosinophilic intranuclear inclusion bodies consistent with herpesviral infection. In addition, large numbers of botryoid intracytoplasmic inclusion bodies were present in the skin, oral mucosa, and bursa of Fabricius, suggestive of circoviral infection, which was confirmed by immunohistochemistry. The concurrent viral load of CoHV1 and PiCV was high in liver, oropharynx, and bursa of Fabricius. We found PiCV in oro-cloacal swabs from 44 of 46 additional birds of variable clinical status, PiCV alone in 23 birds, and coinfection with CoHV1 in 21 birds. Viral copy numbers were significantly higher (p < 0.0001) for both viruses in clinically affected pigeons than in subclinical qPCR-positive birds. The CoHV1-induced lesions might have been exacerbated by concomitant PiCV infection.


Asunto(s)
Enfermedades de las Aves , Infecciones por Circoviridae , Circovirus , Coinfección , Animales , Columbidae , Enfermedades de las Aves/epidemiología , Carga Viral/veterinaria , Coinfección/veterinaria , Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/veterinaria
9.
Res Vet Sci ; 158: 84-95, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36958176

RESUMEN

Porcine Reproductive and Respiratory Syndrome (PRRS) threats the swine industry seriously. The spread of live vaccine virus leads to the emergence of recombinant virus, which brings biosafety problems. The replication-deficient virus as a vaccine candidate would avoid this problem. In the present study, the recombinant lentiviral plasmid pLV-EF1α-EGFP-2A-ORF4 was co-transfected with lentivirus in HEK293FT cells. The transfection mixture was harvested and transduced into Marc-145 to screen a cell line stably expressing the PRRSV ORF4 with puromycin. The cell line Marc-145-GP4 was confirmed with PCR, RT-PCR, IFA, and Western blotting using a monoclonal antibody against Glycoprotein 4 (GP4) of PRRSV. To obtain a replication-deficient PRRSV, Western blotting the recombinant plasmid pNM09-ΔORF4 was constructed by Overlap PCR and DNA recombinant technology with the pNM09 as a backbone plasmid. The pNM09-ΔORF4 was transfected into Marc-145-GP4 with electroporation after transcription in vitro. The replication-deficient virus was rescued on Marc-145-GP4 cells with trans-complementation of ORF4 gene and verified by RT-PCR and IFA. The results indicated that a cell line Marc-145-GP4 stably expressed PRRSV ORF4 was obtained. The recombinant GP4 was successfully expressed and obtained a monoclonal antibody Anti-A-GP4-70, which can specifically react with the virus. Finally, the replication-deficient virus rNM09-ΔORF4 can be rescued with low titer and could only reproduce on the Marc-145-GP4 cells. Unfortunately, the rNM09-ΔORF4 showed too low virus replication titer to determine it. This study lays the foundation for the rapid detection of PRRS and the functional study of GP4 and provides experience for replication-deficient PRRSV.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Animales , Porcinos , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Carga Viral/veterinaria , Línea Celular , Glicoproteínas , Anticuerpos Monoclonales , Replicación Viral/genética
10.
Zool Res ; 43(6): 1041-1062, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36349357

RESUMEN

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes diverse clinical manifestations and tissue injuries in multiple organs. However, cellular and molecular understanding of SARS-CoV-2 infection-associated pathology and immune defense features in different organs remains incomplete. Here, we profiled approximately 77 000 single-nucleus transcriptomes of the lung, liver, kidney, and cerebral cortex in rhesus macaques ( Macaca mulatta) infected with SARS-CoV-2 and healthy controls. Integrated analysis of the multi-organ dataset suggested that the liver harbored the strongest global transcriptional alterations. We observed prominent impairment in lung epithelial cells, especially in AT2 and ciliated cells, and evident signs of fibrosis in fibroblasts. These lung injury characteristics are similar to those reported in patients with coronavirus disease 2019 (COVID-19). Furthermore, we found suppressed MHC class I/II molecular activity in the lung, inflammatory response in the liver, and activation of the kynurenine pathway, which induced the development of an immunosuppressive microenvironment. Analysis of the kidney dataset highlighted tropism of tubule cells to SARS-CoV-2, and we found membranous nephropathy (an autoimmune disease) caused by podocyte dysregulation. In addition, we identified the pathological states of astrocytes and oligodendrocytes in the cerebral cortex, providing molecular insights into COVID-19-related neurological implications. Overall, our multi-organ single-nucleus transcriptomic survey of SARS-CoV-2-infected rhesus macaques broadens our understanding of disease features and antiviral immune defects caused by SARS-CoV-2 infection, which may facilitate the development of therapeutic interventions for COVID-19.


Asunto(s)
COVID-19 , Animales , COVID-19/genética , COVID-19/veterinaria , Macaca mulatta , SARS-CoV-2 , Transcriptoma , Carga Viral/veterinaria
11.
J Vector Borne Dis ; 59(2): 190-192, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36124487

RESUMEN

Japanese encephalitis (JE) is a mosquito borne viral zoonotic disease and JE virus (JEV) is responsible for causing several children deaths every year in India. Since 1978, cases of JE have been reported from Gorakhpur district of Uttar Pradesh state annually. The knowledge on the role played by wildlife reservoirs in the sylvatic transmission and maintenance of JE virus remains limited. Bats are reservoir hosts for several emerging and re-emerging viral pathogens but their role in zoonotic cycle of JEV has not been elucidated yet. In Gorakhpur district of Uttar Pradesh, 52 fruit bats were found dead on 26 May 2020. The post-mortem report of the bat samples conducted at the Indian Veterinary Research Institute stated that the bats died due to brain hemorrhage, caused by excessive heat. The brain tissue samples of the bats were subjected to investigation using molecular techniques to determine the presence of JEV. The present work reports for the first time the detection of JEV in brain samples of bats from India. The viral load ranging from 8 to 18 copies/reaction was detected in brain samples by TaqMan real Time RT-PCR. The low viral load might be the reason for the absence of apparent clinical signs in bats and suggests the probable role of fruit bats in maintaining the JEV in nature.


Asunto(s)
Quirópteros/virología , Virus de la Encefalitis Japonesa (Especie)/aislamiento & purificación , Encefalitis Japonesa/veterinaria , Animales , Encéfalo/patología , Encéfalo/virología , Niño , Reservorios de Enfermedades/virología , Virus de la Encefalitis Japonesa (Especie)/genética , Encefalitis Japonesa/diagnóstico , Encefalitis Japonesa/epidemiología , Humanos , India/epidemiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Carga Viral/veterinaria , Zoonosis Virales/epidemiología
12.
Br Poult Sci ; 63(4): 484-492, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35179081

RESUMEN

1. The role of the Harderian gland (HG), choanal cleft (CC) and turbinate in terms of IBV M41 viral load compared to the trachea, and immune (innate, cellular and mucosal) responses were studied in 21-day-old commercial broiler chickens.2. After virulent IBV M41 challenge, the antigen concentration detected either by quantitative RT-PCR or immunohistochemistry peaked at 2-3 days post challenge (dpc) in all tissues. Significant increases of lachrymal IBV-specific IgA and IgY levels were found at 4-5 dpc.3. Gene transcription showed a significant up-regulation of TLR3, MDA5, IL-6, IFN-α and IFN-ß, where patterns and magnitude fold-change of mRNA transcription were dependent on the gene and tissue type.4. The results demonstrated active IBV M41 replication in the HG, CC and turbinate, comparable to levels of replication found in the trachea. Data on immune-related genes in head-associated tissues provide further understanding on the immunobiology of IBV and offer opportunities to identify their use as quantitative biomarkers in pathogenicity and vaccination-challenge studies.


Asunto(s)
Infecciones por Coronavirus , Glándula de Harder , Virus de la Bronquitis Infecciosa , Enfermedades de las Aves de Corral , Animales , Pollos/genética , Infecciones por Coronavirus/veterinaria , Inmunidad , Virus de la Bronquitis Infecciosa/genética , Tráquea , Cornetes Nasales , Carga Viral/veterinaria
13.
J Vet Med Sci ; 84(3): 350-357, 2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35046241

RESUMEN

Bovine leukemia virus (BLV) is an important pathogen associated with enzootic bovine leukosis. In this study, we performed PCR and sequencing analysis to characterize BLVgp51 sequences from formalin-fixed paraffin-embedded (FFPE) specimens made from 1974 to 2000 and successfully obtained BLV proviral genome sequences from 94% of the analyzed samples. Furthermore, from these samples, we reconstructed eight full-length and nearly full-length BLVgp51 sequences. These sequences were classified as BLV genotype 1, implying that genotype1 has already been circulating in Japan since the 1970s. In our results, the proviral DNA was detected in the 1970s, 1980s, and 1990s in the same manner, indicating that the detection of BLV proviral genome depends on storage conditions rather than storage period. The sequences obtained in this study provide direct insights into BLV sequences before 2000, which serves as a good calibrator for inferring ancient BLV diversity.


Asunto(s)
Enfermedades de los Bovinos , Leucosis Bovina Enzoótica , Virus de la Leucemia Bovina , Animales , Bovinos , Leucosis Bovina Enzoótica/diagnóstico , Formaldehído , Japón/epidemiología , Virus de la Leucemia Bovina/genética , Adhesión en Parafina/veterinaria , Carga Viral/veterinaria
14.
Viruses ; 14(1)2022 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-35062316

RESUMEN

Vaccines against Marek's disease can protect chickens against clinical disease; however, infected chickens continue to propagate the Marek's disease virus (MDV) in feather follicles and can shed the virus into the environment. Therefore, the present study investigated if MDV could induce an immunoregulatory microenvironment in feathers of chickens and whether vaccines can overcome the immune evasive mechanisms of MDV. The results showed an abundance of CD4+CD25+ and CD4+ transforming growth factor-beta (TGF-ß)+ T regulatory cells in the feathers of MDV-infected chickens at 21 days post-infection. In contrast, vaccinated chickens had a lower number of regulatory T cells. Furthermore, the expression of TGF-ß and programmed cell death receptor (PD)-1 increased considerably in the feathers of Marek's disease virus-infected chickens. The results of the present study raise the possibility of an immunoregulatory environment in the feather pulp of MDV-infected chickens, which may in turn favor replication of infectious MDV in this tissue. Exploring the evasive strategies employed by MDV will facilitate the development of control measures to prevent viral replication and transmission.


Asunto(s)
Pollos/virología , Plumas/virología , Enfermedad de Marek/inmunología , Animales , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Expresión Génica , Herpesvirus Gallináceo 2/inmunología , Enfermedad de Marek/virología , Vacunas contra la Enfermedad de Marek/inmunología , Bazo/inmunología , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Vacunación , Carga Viral/veterinaria , Replicación Viral/fisiología
15.
HLA ; 99(2): 105-112, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34854239

RESUMEN

Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis. Polymorphism in bovine leukocyte antigen (BoLA)-DRB3 allele can influence the host immune response to pathogens, including BLV. However, association between specific BoLA-DRB3 alleles and BLV proviral load (PVL), which is a useful index for estimating disease progression and transmission risk, in Vietnamese cattle are unknown. Here, association study of BoLA-DRB3 allele frequency between cattle with high or low PVL demonstrated BoLA-DRB3*12:01 associates with high PVL in Vietnamese Holstein Friesian (HF) crossbred cattle. This is the first study to demonstrate that BoLA-DRB3 polymorphism confers susceptibility to BLV high PVL in HF crossbred kept in Vietnam. Our results may be useful in disease control and eradiation for BLV through genetic selection.


Asunto(s)
Bovinos , Virus de la Leucemia Bovina , Alelos , Animales , Bovinos/genética , Antígenos de Histocompatibilidad Clase II/genética , Virus de la Leucemia Bovina/genética , Provirus/genética , Vietnam , Carga Viral/veterinaria
16.
Transbound Emerg Dis ; 69(2): 195-203, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34606685

RESUMEN

In humans, co-infection of hepatitis B and C viruses (HBV, HCV) is common and aggravates disease outcome. Infection-mediated disease aggravation is poorly understood, partly due to lack of suitable animal models. Carnivores are understudied for hepatitis virus homologues. We investigated Mexican carnivores (ringtails, Bassariscus astutus) for HBV and HCV homologues. Three out of eight animals were infected with a divergent HBV termed ringtail HBV (RtHBV) at high viral loads of 5 × 109 -1.4 × 1010 copies/ml serum. Two of the RtHBV-infected animals were co-infected with a divergent hepacivirus termed ringtail hepacivirus (RtHV) at 4 × 106 -7.5 × 107 copies/ml in strain-specific qRT-PCR assays. Immunofluorescence assays relying on HBV core and RtHV NS3/4a proteins indicated that none of the animals had detectable hepadnavirus core-specific antibodies, whereas one RtHV-infected animal had concomitant RtHV-specific antibodies at 1:800 end-point titre. RtHBV and RtHV complete genomes showed typical HBV and HCV structure and length. All RtHBV genomes were identical, whereas RtHV genomes showed four amino acid substitutions located predominantly in the E1/E2-encoding genomic regions. Both RtHBV (>28% genomic nucleotide sequence distance) and RtHV (>30% partial NS3/NS5B amino acid sequence distance) formed new species within their virus families. Evolutionary analyses showed that RtHBV grouped with HBV homologues from different laurasiatherian hosts (carnivores, bats, and ungulates), whereas RtHV grouped predominantly with rodent-borne viruses. Ancestral state reconstructions showed that RtHV, but not RtHBV, likely emerged via a non-recent host switch involving rodent-borne hepacivirus ancestors. Conserved hepatitis virus infection patterns in naturally infected ringtails indicate that carnivores may be promising animal models to understand HBV/HCV co-infection.


Asunto(s)
Coinfección , Hepatitis B , Animales , Coinfección/veterinaria , Hepacivirus/genética , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Hepatitis B/veterinaria , Virus de la Hepatitis B/genética , Carga Viral/veterinaria
17.
J Anim Sci ; 99(11)2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34734242

RESUMEN

Thyroid hormones are powerful regulators of growth, development, and basal metabolic rate and can be dysregulated under conditions of severe stress or illness. To understand the role of these hormones in porcine disease response, serum samples were obtained from three batches of nursery-aged pigs (n = 208) exposed to a natural polymicrobial disease challenge with an array of bacterial and viral pathogens. Levels of total thyroxin (T4) and triiodothyronine (T3) assessed in sera by radioimmunoassay, decreased significantly by 14 days post-exposure (DPE). Levels of T3 partially rebounded by 48 DPE, while T4 levels remain depressed. Post-exposure T3 and T4 levels were positively correlated with acute and long-term average daily gain (ADG). Cross-sectional sampling of animals maintained at the high health source farms, showed no equivalent change in either hormone when managed under standard industrial conditions. To further elucidate the effect of porcine reproductive and respiratory syndrome virus (PRRSV)-infection on thyroid hormone levels, archived sera over 42 days post inoculation (DPI) from nursery pigs (N = 190) challenged with one of two PRRSV2 strains by the PRRS Host Genetics Consortium were similarly assessed, with animals selected in a two-by-two design, to investigate biological extremes in ADG and viral load (VL). All animals showed a similar decrease in both thyroid hormones reaching a minimum at 7 DPI and returning to near pre-challenge levels by 42 DPI. Post-challenge T3 and T4 levels were significantly greater in high ADG groups, with no significant association with VL or strain. The results of this study demonstrate porcine susceptibility to thyroid disruption in response to disease challenge and demonstrate a relationship between this response and growth performance.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Animales , Anticuerpos Antivirales , Estudios Transversales , Porcinos , Hormonas Tiroideas , Carga Viral/veterinaria
18.
Comp Immunol Microbiol Infect Dis ; 79: 101709, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34543808

RESUMEN

African swine fever (ASF) causes a contagious hemorrhagic disease in all ages of pigs without sex predilections. The objective of this study was to determine the age-related viral loads and severity of systemic pathological lesions among three different swine group ages (weaned pigs, fattening pigs, and sows) during a recent outbreak of acute ASF in Vietnam. Age-related viral loads were determined in 5 major organs (lung, liver, spleen, kidney, and lymph node) by immunohistochemistry as well as in the blood by real-time polymerase chain reaction (PCR). Age-related systemic pathological lesions were analyzed in the listed organs among three age groups. Weaned pigs had significantly (p < 0.05) higher levels of viral loads in their lung, liver, lymph nodes and blood than in those of fattening pigs and sows. Fattening pigs had significantly (p < 0.05) higher scores of macroscopic lung and lymphoid lesions, and microscopic liver lesions compared with those of weaned pigs and sows. The results of this study demonstrated that viral loads were age-related in acute naturally occurring ASF but the severity of pathological lesions was not correlated with the level of viral loads in the five major organs.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Enfermedades de los Porcinos , Fiebre Porcina Africana/epidemiología , Virus de la Fiebre Porcina Africana/genética , Animales , Brotes de Enfermedades , Femenino , Genotipo , Sus scrofa , Porcinos , Carga Viral/veterinaria
19.
Vet Microbiol ; 262: 109243, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34563884

RESUMEN

SARS-CoV-2 infects several animal species and SARS-CoV-2 variants of concern (VOCs) may even show (as in humans) enhanced inter- and intra-species transmission rates. We correlated sensitivity data of SARS-CoV-2 rapid antigen tests (RATs) to viral RNA genome equivalents analyzed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Further, we checked their suitability for testing animals by assessing saliva and VOC effects. Viral loads up to 2 logs (RNA copy number) under the hypothetical SARS-CoV-2 infectivity threshold were detected by most analyzed RATs. However, while saliva from various animal species showed generally no adverse effects on the RATs' analytical sensitivities, the detection of VOCs B.1.1.7 and B.1.351 was in some RATs inferior to non-VOC viruses.


Asunto(s)
Antígenos Virales/aislamiento & purificación , Prueba Serológica para COVID-19/veterinaria , COVID-19/veterinaria , Variación Genética , SARS-CoV-2/aislamiento & purificación , Saliva/virología , Animales , COVID-19/diagnóstico , COVID-19/virología , Prueba Serológica para COVID-19/normas , Chlorocebus aethiops , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Células Vero , Carga Viral/veterinaria
20.
Vet Microbiol ; 261: 109200, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34371437

RESUMEN

Bovine leukemia virus (BLV) infects bovine B-cells and causes malignant lymphoma, resulting in severe economic losses in the livestock industry. To control the spread of BLV, several studies have attempted to clarify the molecular mechanisms of BLV pathogenesis, but the details of the mechanism are still enigmatic. Currently, viral non-coding RNAs are attracting attention as a novel player for BLV pathogenesis because these transcripts can evade the host immune response and are persistently expressed in latent infection. One of the viral non-coding RNA, AS1, is encoded in the antisense strand of the BLV genome and consists of two isoforms, AS1-L and AS1-S. Although the function of the AS1 is still unknown, the AS1 RNA might also have some roles because it keeps expressing in tumor tissues. In the present study, we identified novel single nucleotide polymorphisms (SNPs) located in the AS1 coding region and indicated that individuals infected with BLV with minor SNPs showed low proviral load. To evaluate the effect of identified SNPs, we constructed infectious clones with these SNPs and found that their introduction affected the expression profile of AS1 RNA; the amount of AS1-L isoform increased compared with the wild type, although the total amount of AS1 RNA remained unchanged. Prediction analysis also suggested that the introduction of SNPs changed the secondary structure of AS1 RNA. These results explain part of the relationship between BLV expansion in vivo and the expression profile of AS1, although further analysis is required.


Asunto(s)
Linfocitos B/virología , Leucosis Bovina Enzoótica/virología , Regulación Viral de la Expresión Génica/genética , Genoma Viral/genética , Virus de la Leucemia Bovina/genética , Provirus/fisiología , Animales , Bovinos , Perfilación de la Expresión Génica , Polimorfismo de Nucleótido Simple , Carga Viral/veterinaria
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