1
|
Dastjerdi A, Strong R, La Rocca SA, Wessels M, Wessels J, Whitaker K, Strugnell B, Williamson S. Investigation into an outbreak of Border disease virus in pigs in England. Transbound Emerg Dis 2022; 69:1698-1706. [PMID: 35353447 PMCID: PMC9544453 DOI: 10.1111/tbed.14539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/09/2022] [Accepted: 03/24/2022] [Indexed: 11/30/2022]
Abstract
Border disease (BD) was first reported in 1959 in lambs from the border region of England and Wales. The causative virus (BD virus; BDV) has since been identified in several other ruminant species and pigs. The virus is prevalent in sheep flocks of UK, Europe and USA and has potential to inflict substantial economic losses. Natural BDV infection of pigs was first reported in the UK in 1992 from pigs with haemorrhagic lesions and more recently from healthy pigs in Spain and Japan. Here, a persistent problem of poor growth and anaemia in a small proportion of growing pigs on a mixed pig and sheep holding was investigated and tissues were tested in a pan viral microarray. The microarray detected BDV RNA in several tissues which was further confirmed by sequencing, specific BDV PCR and immunohistochemistry. Phylogenetically, the virus clustered with other BDVs in the sub‐genotype 1b. This investigation highlights likely interspecies transmission of pestiviruses and their impact on pestivirus detection and eradication programs.
Collapse
Affiliation(s)
- Akbar Dastjerdi
- Virology department, Animal and Plant Health Agency (APHA)-Weybridge, Addlestone, Surrey, KT15 3NB, UK
| | - Rebecca Strong
- Virology department, Animal and Plant Health Agency (APHA)-Weybridge, Addlestone, Surrey, KT15 3NB, UK
| | - S Anna La Rocca
- Virology department, Animal and Plant Health Agency (APHA)-Weybridge, Addlestone, Surrey, KT15 3NB, UK
| | - Mark Wessels
- APHA-Preston, Animal Health Centre, Barton Hall, Garstang Road, Barton, Preston, . PR3 5HE, UK
| | - Julie Wessels
- APHA-Bury St. Edmunds, Rougham Hill, Bury St Edmunds, Suffolk, IP33 2RX, UK
| | - Kate Whitaker
- APHA-Preston, Animal Health Centre, Barton Hall, Garstang Road, Barton, Preston, . PR3 5HE, UK
| | - Ben Strugnell
- APHA-Thirsk, West House, Station Road, Thirsk, YO7 1PZ, UK
| | - Susanna Williamson
- APHA-Bury St. Edmunds, Rougham Hill, Bury St Edmunds, Suffolk, IP33 2RX, UK
| |
Collapse
|
2
|
Montgomery DL. Distribution and Cellular Heterogeneity of Bovine Viral Diarrhea Viral Antigen Expression in the Brain of Persistently Infected Calves: A New Perspective. Vet Pathol 2016; 44:643-54. [PMID: 17846236 DOI: 10.1354/vp.44-5-643] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Persistent infection following in utero exposure to bovine viral diarrhea virus (BVDV) early in gestation is a serious cause of morbidity and mortality in cattle industries worldwide. The brain is a primary target of persistent infection. In the current study, the types of cells infected and topography of viral antigen expression were examined in brain sections from 9 BVDV persistently infected crossbred calves, all less than 1 year of age, by immunohistochemical staining using the 15C5 primary monoclonal antibody. BVDV antigen was detected in the brains of all persistently infected calves. A variety of cell types was infected, including neurons, astrocytes, oligodendroglia, blood vessel-associated cells (pericytes, perivascular macrophages, smooth muscle cells), and cells in the leptomeninges (blood vessel-associated cells). Conclusive demonstration of viral antigen in vascular endothelial cells was elusive. The intensity and distribution of viral antigen staining in neurons were highly variable. Viral antigen staining was most consistent and intense in thalamic nuclei, most notably in dorsal and medial nuclear groups, followed by the hippocampus, entorhinal cortex, basal nuclei, and piriform cortex. Staining in other brain areas was often less intense and inconsistent. The variability in the intensity and topography of viral antigen in the brain may explain the heterogeneity in the clinical manifestations of BVDV-induced disease. Additionally, infection of the brain in persistently infected calves may underlie or at least contribute to endocrine disturbances and immunologic deficits that are protean manifestations of BVDV-induced disease.
Collapse
Affiliation(s)
- D L Montgomery
- Department of Veterinary Sciences, College of Agriculture, University of Wyoming, Laramie, WY 82070, USA.
| |
Collapse
|
3
|
Confer AW, Fulton RW, Step DL, Johnson BJ, Ridpath JF. Viral Antigen Distribution in the Respiratory Tract of Cattle Persistently Infected with Bovine Viral Diarrhea Virus Subtype 2a. Vet Pathol 2016; 42:192-9. [PMID: 15753473 DOI: 10.1354/vp.42-2-192] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tissues were obtained at necropsy from the nasal vestibule, turbinates, nasopharynx, trachea, tracheobronchial bifurcation, and lung from each of 10 clinically healthy calves persistently infected (PI) with bovine viral diarrhea virus (BVDV) serotype 2a. Tissues from the nasal vestibule were obtained by biopsy from five additional PI calves. Formalin-fixed tissues were processed for immunohistochemistry to localize the distribution of BVDV throughout the respiratory tract. Antigen distribution and intensity were subjectively evaluated. Throughout the respiratory tract, mononuclear leukocytes, vascular smooth muscle, and endoneural and perineural cells had BVDV immunoreactivity (BVDV-IR). Multifocally, squamous and ciliated columnar epithelium throughout the respiratory tract contained weak to moderate BVDV antigen. Viral antigen was not seen in goblet cells. BVDV-IR in mixed tubuloalveolar glands of the nasal cavity was weak to strong in serous secretory cells and ductular epithelium. Chondrocytes of the concha often contained BVDV antigen diffusely. Nasal mucus-secreting and tracheobronchial glands multifocally contained weak viral signal. In all cases, alveolar macrophages had moderate to strong BVDV-IR, whereas BVDV-IR in alveolar epithelial cells was weak to moderate. BVDV was present in interalveolar leukocytes and mesenchymal cells. Results indicate that serous secretions of the nasal cavity, productive viral infection of epithelium, and infected leukocytes in respiratory secretions are likely major sources of infectious BVDV from PI calves. The presence of BVDV antigen in respiratory epithelium is, at least, indirect support for the notion that this virus predisposes PI cattle to secondary microbial infections.
Collapse
Affiliation(s)
- A W Confer
- Department of Veterinary Pathobiology and the Oklahoma Animal Disease Diagnostic Laboratory, 211 McElroy Hall, Oklahoma State University, Stillwater, OK 74078-2007, USA.
| | | | | | | | | |
Collapse
|
4
|
Seyfi Abad Shapouri MR, Ekhtelat M, Ghorbanpoor Najaf Abadi M, Mahmoodi Koohi P, Lotfi M. Production of Monoclonal Antibody Against Recombinant Polypeptide From the Erns Coding Region of the Bovine Viral Diarrhea Virus. Jundishapur J Microbiol 2016; 8:e26727. [PMID: 26870309 PMCID: PMC4746439 DOI: 10.5812/jjm.26727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 06/07/2015] [Accepted: 07/06/2015] [Indexed: 11/16/2022] Open
Abstract
Background: Bovine viral diarrhea (BVD) is an economically important cattle disease with a worldwide distribution. Detection and elimination of animals persistently infected (PI) with bovine viral diarrhea virus (BVDV) is essential for the control of BVD and eradication of BVDV. There are usually no pathognomonic clinical signs of BVDV infection. Diagnostic investigations therefore rely on laboratory-based detection of the virus, or virus-induced antigens or antibodies. Objectives: Erns as an immunogenic protein of BVDV, is genetically and antigenically conserved among different isolates and therefore, is a candidate antigen for development of the enzyme linked immunosorbent assay (ELISA) for serological studies or identification of PI animals. The aim of this study was to produce a monoclonal antibody (MAb) against recombinant Erns. Materials and Methods: For this purpose, recombinant maltose-binding protein (MBP)-Erns protein was expressed in Escherichia coli and purified using amylose resin chromatography column and used as an antigen in MAb production. Spleen cells of the immunized mice with the recombinant antigen were fused with SP2/0 myeloma cells. Next, culture supernatants of primary clones of fused cells were screened by indirect ELISA. After three rounds of cloning, the reactivity of the MAbs with recombinant and natural antigen was established by Western blotting. Results: Based on our results, MAb against recombinant Erns was produced and reacted successfully with recombinant and natural antigens. Conclusions: With regards to the role of Erns in the identification of PI animals, it appears that Erns recombinant antigen and the specific monoclonal antibodies produced against it may be suitable for developing BVDV laboratory diagnostic assays.
Collapse
Affiliation(s)
| | - Maryam Ekhtelat
- Department of Pharmacognosy, Faculty of Pharmacy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
- Corresponding author: Maryam Ekhtelat, Department of Pharmacognosy, Faculty of Pharmacy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran. Tel: +98-9161130232, Fax: +98-6133333936, E-mail:
| | | | - Pezhman Mahmoodi Koohi
- Department of Pathobiology, Faculty of Para Veterinary Science, Bu-Ali Sina University, Hamedan, IR Iran
| | - Mohsen Lotfi
- Department of Quality Control, Razi Vaccine and Serum Research Institute, Karaj, IR Iran
| |
Collapse
|
5
|
Passler T, Riddell KP, Edmondson MA, Chamorro MF, Neill JD, Brodersen BW, Walz HL, Galik PK, Zhang Y, Walz PH. Experimental infection of pregnant goats with bovine viral diarrhea virus (BVDV) 1 or 2. Vet Res 2014; 45:38. [PMID: 24708266 PMCID: PMC3994200 DOI: 10.1186/1297-9716-45-38] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 03/11/2014] [Indexed: 12/15/2022] Open
Abstract
Infections with bovine viral diarrhea virus (BVDV) of the genus pestivirus, family Flaviviridae, are not limited to cattle but occur in various artiodactyls. Persistently infected (PI) cattle are the main source of BVDV. Persistent infections also occur in heterologous hosts such as sheep and deer. BVDV infections of goats commonly result in reproductive disease, but viable PI goats are rare. Using 2 BVDV isolates, previously demonstrated to cause PI cattle and white-tailed deer, this study evaluated the outcome of experimental infection of pregnant goats. Pregnant goats (5 goats/group) were intranasally inoculated with BVDV 1b AU526 (group 1) or BVDV 2 PA131 (group 2) at approximately 25-35 days of gestation. The outcome of infection varied considerably between groups. In group 1, only 3 does became viremic, and 1 doe gave birth to a stillborn fetus and a viable PI kid, which appeared healthy and shed BVDV continuously. In group 2, all does became viremic, 4/5 does aborted, and 1 doe gave birth to a non-viable PI kid. Immunohistochemistry demonstrated BVDV antigen in tissues of evaluated fetuses, with similar distribution but reduced intensity as compared to cattle. The genetic sequence of inoculated viruses was compared to those from PI kids and their dam. Most nucleotide changes in group 1 were present during the dam's acute infection. In group 2, a similar number of mutations resulted from fetal infection as from maternal acute infection. Results demonstrated that BVDV may cause reproductive disease but may also be maintained in goats.
Collapse
Affiliation(s)
- Thomas Passler
- College of Veterinary Medicine, Departments of Clinical Sciences and Pathobiology, Auburn University, Auburn, AL 36849, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Colloff A, Watson P, Paul Duff J, Scholes S. Haemorrhagic disease in cattle with genotype 1 bovine viral diarrhoea virus infection. Vet Rec 2012; 171:530. [DOI: 10.1136/vr.100497] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- A. Colloff
- Animal Health and Veterinary Laboratories Agency (AHVLA); AHVLA-Truro; Truro TR4 9AD UK
| | - P. Watson
- Animal Health and Veterinary Laboratories Agency (AHVLA); AHVLA-Penrith; Penrith UK
| | - J. Paul Duff
- Animal Health and Veterinary Laboratories Agency (AHVLA); AHVLA-Penrith; Penrith UK
| | - S. Scholes
- Animal Health and Veterinary Laboratories Agency (AHVLA); AHVLA-Lasswade; Penicuik UK
| |
Collapse
|
7
|
Henningson JN, Steffen DJ, Topliff CL, Kurth KL, Dubielzig RR, Brodersen BW, Bedenice D, Eskridge KM, Callan RJ, Reggiardo C, Rupp GP, Kelling CL. Systemic Distribution of Viral Antigen in Alpacas Persistently Infected With Bovine Pestivirus. Vet Pathol 2012; 50:308-17. [DOI: 10.1177/0300985812447827] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recently, confirmed occurrences of persistent bovine viral diarrhea virus (BVDV) infection in North American alpacas have raised concerns about the role of persistently infected (PI) alpacas in transmission of virus among herds, yet only limited pathological descriptions of persistent infections in alpacas have been reported. The objective of this study was to characterize BVDV antigen distribution in 10 PI alpacas of varying age and to compare viral antigen distribution and localization in tissues of PI alpacas with 5 PI calves of varying age. Ocular dysplasia was evident in 1 PI alpaca, constituting the first reported congenital ocular lesion in PI alpacas. Viral antigen was widely distributed in alpaca tissues and was prominent in neurons, endothelial cells, and vascular tunica media myocytes but had limited distribution in lymphoid tissues and moderate distribution in epithelium of several organ systems of alpacas. Macrophages in the alpaca gastrointestinal system submucosa and lymph node medullary sinuses often had prominent labeling. In addition, only 1 alpaca had antigen labeling in the bone marrow in contrast to PI cattle. Labeled cells in calf tissues were more widely distributed, occurring prominently in lymphoid and epithelial tissues. Common features of the 2 host species were widespread antigen labeling and absence of lymphoid depletion.
Collapse
Affiliation(s)
- J. N. Henningson
- School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska, Lincoln, Nebraska
- Current address: Kansas State Veterinary
Diagnostic Laboratory, Kansas State University, Manhattan, Kansas
| | - D. J. Steffen
- School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska, Lincoln, Nebraska
| | - C. L. Topliff
- School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska, Lincoln, Nebraska
| | - K. L. Kurth
- Wisconsin Veterinary Diagnostic Laboratory,
Madison, Wisconsin
| | - R. R. Dubielzig
- Department of Pathobiology, University of
Wisconsin School of Veterinary Medicine, Madison, Wisconsin
| | - B. W. Brodersen
- School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska, Lincoln, Nebraska
| | - D. Bedenice
- Cummings School of Veterinary Medicine, Tufts
University, North Grafton, Massachusetts
| | - K. M. Eskridge
- Department of Statistics, University of
Nebraska, Lincoln, Nebraska
| | - R. J. Callan
- College of Veterinary Medicine, Colorado State
University, Fort Collins, Colorado
| | - C. Reggiardo
- Arizona Veterinary Diagnostic Laboratory,
University of Arizona, Tucson, Arizona
| | - G. P. Rupp
- School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska, Lincoln, Nebraska
| | - C. L. Kelling
- School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska, Lincoln, Nebraska
| |
Collapse
|
8
|
Passler T, Walz HL, Ditchkoff SS, van Santen E, Brock KV, Walz PH. Distribution of bovine viral diarrhoea virus antigen in persistently infected white-tailed deer (Odocoileus virginianus). J Comp Pathol 2012; 147:533-41. [PMID: 22520818 DOI: 10.1016/j.jcpa.2012.02.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 02/02/2012] [Accepted: 02/27/2012] [Indexed: 10/28/2022]
Abstract
Infection with bovine viral diarrhoea virus (BVDV), analogous to that occurring in cattle, is reported rarely in white-tailed deer (Odocoileus virginianus). This study evaluated the distribution of BVDV antigen in persistently infected (PI) white-tailed deer and compared the findings with those from PI cattle. Six PI fawns (four live-born and two stillborn) from does exposed experimentally to either BVDV-1 or BVDV-2 were evaluated. Distribution and intensity of antigen expression in tissues was evaluated by immunohistochemistry. Data were analyzed in binary fashion with a proportional odds model. Viral antigen was distributed widely and was present in all 11 organ systems. Hepatobiliary, integumentary and reproductive systems were respectively 11.8, 15.4 and 21.6 times more likely to have higher antigen scores than the musculoskeletal system. Pronounced labelling occurred in epithelial tissues, which were 1.9-3.0 times likelier than other tissues to contain BVDV antigen. Antigen was present in >90% of samples of liver and skin, suggesting that skin biopsy samples are appropriate for BVDV diagnosis. Moderate to severe lymphoid depletion was detected and may hamper reliable detection of BVDV in lymphoid organs. Muscle tissue contained little antigen, except for in the cardiovascular system. Antigen was present infrequently in connective tissues. In nervous tissues, antigen expression frequency was 0.3-0.67. In the central nervous system (CNS), antigen was present in neurons and non-neuronal cells, including microglia, emphasizing that the CNS is a primary target for fetal BVDV infection. BVDV antigen distribution in PI white-tailed deer is similar to that in PI cattle.
Collapse
Affiliation(s)
- T Passler
- Department of Clinical Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL, USA.
| | | | | | | | | | | |
Collapse
|
9
|
Santos AS, Antoniassi NA, Boabaid FM, Bitencourt AP, Almeida LL, Canal CW, Flores EF, Driemeier D. Aspectos clínicos, patológicos, imuno-histoquímicos e virológicos em cinco bezerros persistentemente infectados com o vírus da diarreia viral bovina em uma propriedade do Rio Grande do Sul. PESQUISA VETERINARIA BRASILEIRA 2011. [DOI: 10.1590/s0100-736x2011001000009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
O vírus da diarreia viral bovina (BVDV) é responsável por diferentes síndromes que afetam bovinos em todo o mundo, causando grandes perdas econômicas. O presente trabalho analisou as características clínicas, patológicas e imuno-histoquímicas e virais de cinco bovinos persistentemente infectados pelo BVDV de uma mesma propriedade, localizada no Município de Viamão, Rio Grande do Sul. Dentre os sinais clínicos verificados destacaram-se subdesenvolvimento, secreções nasais e oculares, além de catarata congênita unilateral em dois bovinos. As principais lesões observadas durante a necropsia consistiram de aumento dos linfonodos mesentéricos, evidenciação das placas de Peyer e pododermatite e lesões crostosas no plano nasal e na região periocular em um animal. Os achados microscópicos caracterizavam-se, principalmente, por infiltrado mononuclear na lâmina do intestino delgado e rarefação linfoide com infiltrado histiocitário nos centrofoliculares de linfonodos e nas placas de Peyer. Antígenos virais foram detectados por imuno-histoquímica principalmente em queratinócitos da epiderme, no epitélio de folículos pilosos e células mononucleares da derme de orelhas e pele; histiócitos e em linfócitos dos linfonodos; células foliculares da tireoide; no citoplasma de neurônios e, em menor escala, em células da micróglia no córtex cerebral e no hipocampo. O isolamento viral de amostras de sangue e órgãos dos animais confirmou a presença de BVDV não citopático. Também foi possível detectar a presença do genoma viral por RT-PCR no soro dos animais. A análise filogenética do fragmento parcial da região 5' não traduzida do genoma viral permitiu a classificação da amostra viral como BVDV tipo 2b. O presente estudo reforça a necessidade de investigar e caracterizar surtos de BVD e descrever suas diferentes for-mas de apresentação.
Collapse
|
10
|
Otter A, Welchman DDB, Sandvik T, Cranwell MP, Holliman A, Millar MF, Scholes SFE. Congenital tremor and hypomyelination associated with bovine viral diarrhoea virus in 23 British cattle herds. Vet Rec 2009; 164:771-8. [PMID: 19542551 DOI: 10.1136/vr.164.25.771] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
This paper presents data from 23 British herds investigated between 1991 and 2007 where neurological disease in calves was caused by bovine viral diarrhoea virus (BVDV) infection. A variety of clinical signs, most commonly tremor or trembling, were apparent in the calves from birth, and most were recumbent or unable to stand unsupported. Severe diffuse neuraxial hypomyelination was present in all of the calves, and immunohistochemistry revealed cerebral neuronal labelling consistent with congenital persistent pestivirus infection in each brain. BVDV was detected in peripheral blood samples from eight of 15 calves tested using an antigen ELISA, and was isolated in culture from samples of viscera, brain or blood collected from 17 of 24 affected calves. TaqMan RT-PCR for pestivirus RNA was positive for BVDV-1 in all six calves tested. Six of the virus isolates on which molecular classification was carried out, obtained from calves in four of the herds, were identified as BVDV-1a, while three isolates from one affected and two unaffected calves on a fifth farm were confirmed as BVDV-1b.
Collapse
Affiliation(s)
- A Otter
- Veterinary Laboratories Agency (VLA) - Shrewsbury, Kendal Road, Harlescott, Shrewsbury, UK.
| | | | | | | | | | | | | |
Collapse
|
11
|
Cerebral Segmental Polyarteritis of Unknown Aetiology in Sheep. J Comp Pathol 2009; 140:283-7. [DOI: 10.1016/j.jcpa.2009.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2008] [Revised: 12/17/2008] [Accepted: 01/23/2009] [Indexed: 11/21/2022]
|
12
|
Duncan C, Ridpath J, Palmer MV, Driskell E, Spraker T. Histopathologic and immunohistochemical findings in two white-tailed deer fawns persistently infected with Bovine viral diarrhea virus. J Vet Diagn Invest 2008; 20:289-96. [PMID: 18460614 DOI: 10.1177/104063870802000305] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Bovine viral diarrhea virus (BVDV) is an important pathogen of domestic cattle. Serologic, experimental, and individual case studies explored the presence and pathogenesis of the virus in wild ungulates; however, there remain large gaps in knowledge regarding BVDV infection in nonbovine species. Live twins were born from a white-tailed deer (Odocoileus virginianus) doe infected with noncytopathic BVDV during its first trimester of pregnancy. The twins died at 1 day of age from trauma unrelated to the infection, and tissues were collected for histologic and immunohistochemical examination. The most significant histologic abnormality was diffuse depletion of B-lymphocytes in both fawns. The BVDV antigen was distributed widely throughout many tissues and cell types, most notably epithelium and vascular endothelium, consistent with that reported in cattle. In contrast to cattle, lymphocytes exhibited only very rare positive staining.
Collapse
Affiliation(s)
- Colleen Duncan
- Colorado State University Veterinary Diagnostic Laboratory, Fort Collins, CO 80523, USA.
| | | | | | | | | |
Collapse
|
13
|
Montgomery DL, Van Olphen A, Van Campen H, Hansen TR. The Fetal Brain in Bovine Viral Diarrhea Virus-infected Calves: Lesions, Distribution, and Cellular Heterogeneity of Viral Antigen at 190 Days Gestation. Vet Pathol 2008; 45:288-96. [DOI: 10.1354/vp.45-3-288] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Previous studies have shown that the brain is a target of persistent infection with bovine viral diarrhea virus (BVDV) and have demonstrated viral tropism for neurons as well as other endogenous cell types in diverse brain areas. Apart from foci of mild residual inflammation in some postnatal calves, consistent brain lesions, per se, have not been reported. No similar comprehensive studies of the brain have been reported in bovine fetuses. In the current study, 12 BVDV-seronegative heifers were inoculated intranasally with a 2-ml 4.4 log10 TCID50/ml dose of noncytopathic type 2 BVDV at 75 and 175 days of gestation to create persistently and transiently infected fetuses, respectively. In only persistently infected fetuses, encephaloclastic lesions resulting in pseudocysts were observed in the subependymal zone in the region of the median eminence and adjacent corona radiata as well as in the region of the external capsule associated with lenticulostriate arteries. Additionally, areas of rarefaction in white matter were observed at the tips of cerebrocortical gyri and in the external capsule. The distribution of viral antigen was examined by immunohistochemical labeling using the 15C5 anti-BVDV monoclonal antibody. Viral antigen was detected only in calves inoculated at 75 days of gestation, i.e., persistently infected. The pattern of BVDV immunolabeling revealed both similarities and differences compared with previous studies in postnatal calves, suggesting that viral infection in the brain is a dynamic and progressive rather than static process.
Collapse
Affiliation(s)
- D. L. Montgomery
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY
| | - A. Van Olphen
- Department of Global Health, College of Public Health, University of South Florida, Tampa, FL
| | - H. Van Campen
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO
| | - T. R. Hansen
- Department and Biomedical Sciences, Colorado State University, Fort Collins, CO
| |
Collapse
|
14
|
Gómez-Villamandos JC, García de Leániz I, Núñez A, Salguero FJ, Ruiz-Villamor E, Romero-Trevejo JL, Sánchez-Cordón PJ. Neuropathologic study of experimental classical swine fever. Vet Pathol 2006; 43:530-40. [PMID: 16846995 DOI: 10.1354/vp.43-4-530] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of this study was to report on the lesions occurring in the central nervous system (CNS) during experimental classical swine fever (CSF) to clarify the spatial and chronologic distribution of the lesions and virus antigen in the CNS. To learn more about the pathogenetic mechanisms of the lesions during CSF in the CNS and to investigate the role of the virus in these mechanisms, cellular infiltrates and infected cells have been characterized. Twenty-eight pigs were inoculated with the virulent CSF virus isolate Alfort 187 and slaughtered from 2 to 15 postinoculation days; 4 animals of similar background served as a control group. Immunohistochemistry, electron microscopy, and the transferase-mediated deoxyuridine triphosphate nick-end labeling method were used to detect viral antigens and apoptosis. The results showed the presence of nonpurulent meningoencephalitis, occasional microhemorrhages, and apoptosis of the lymphocytes forming the perivascular and interstitital infiltrate in swine with CSF. Macrophages appeared to display little involvement in CNS lesions. The infected cells observed at the early stage of disease were lymphocytes and microglial cells in the rostral portion of the telencephalon, with infection of these cells in other areas in the next stages. The relationship between these lesions and the presence of viral antigen varied according to the type of lesion: hemorrhages were not associated with the presence of antigen in endothelial cells, but infiltrate-cell apoptosis was temporally and spacially associated to viral infection. However, the link between viral infection and the presence of cell infiltrate was far from clear.
Collapse
Affiliation(s)
- J C Gómez-Villamandos
- Departamento de Anatomía y Anatomía Patológica Comparadas, Facultad de Veterinaria, Universidad de Córdoba, Edificio de Sanidad Animal, Campus de Rabanales, 14014, Córdoba (Spain).
| | | | | | | | | | | | | |
Collapse
|
15
|
Abstract
Infections with bovine viral diarrhoea virus continue to plague the cattle industry worldwide. The wish to control the negative effects of the virus has lead to the development of numerous vaccines, but also of eradication schemes. In this paper, a comprehensive overview on BVDV is given: the virus and its clinical manifestations, its occurrence and economic impact, the different routes of transmission, as well as diagnostic methods and objectives. Furthermore, the two major options for BVDV control--eradication and vaccination--are discussed as well as the risk for reintroduction of BVDV after eradication.
Collapse
|
16
|
Fredriksen B, Press CM, Sandvik T, Odegaard SA, Løken T. Detection of viral antigen in placenta and fetus of cattle acutely infected with bovine viral diarrhea virus. Vet Pathol 1999; 36:267-75. [PMID: 10421093 DOI: 10.1354/vp.36-4-267] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The reproductive organs and fetuses of seven Norwegian Red heifers were investigated for the presence of bovine viral diarrhea virus (BVDV) antigen during the time of initial transplacental transmission of the virus. The heifers were inoculated with a noncytopathogenic BVDV at day 85/86 of gestation and were slaughtered at day 7, 10, 14, 18, or 22 postinoculation (pi). Cryostat sections of uterus, ovaries, placentomes, intercotyledonary fetal membranes, and fetal organs were examined using immunohistochemical techniques. A double immunofluorescence technique was used to identify cells that showed staining with antibodies against the leukocyte common antigen CD45 or the intermediate filament vimentin and BVDV antigens. The earliest stage of infection at which BVDV antigen could be detected in the fetuses was 14 days pi. At this stage, BVDV antigen was detected in cells of mesenchymal origin in the lungs and in large cells that morphologically resembled immature megakaryocytes in the liver. In the intercotyledonary fetal membranes and in the placentomes, BVDV antigen was not detected until 18 and 22 days pi, respectively. BVDV antigen was not detected in maternal tissue from any of the heifers. The present results indicate that fetal infection with BVDV can take place without preceding or simultaneous high concentrations of BVDV in uterus or placenta of acutely infected heifers.
Collapse
Affiliation(s)
- B Fredriksen
- Department of Reproduction and Forensic Medicine, Norwegian School of Veterinary Science, Oslo.
| | | | | | | | | |
Collapse
|
17
|
Sandvik T. Laboratory diagnostic investigations for bovine viral diarrhoea virus infections in cattle. Vet Microbiol 1999; 64:123-34. [PMID: 10028167 DOI: 10.1016/s0378-1135(98)00264-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
There are no pathognomonic clinical signs of infection with bovine viral diarrhoea virus (BVDV) in cattle. Diagnostic investigations therefore rely on laboratory-based detection of the virus, or of virus-induced antigens or antibodies in submitted samples. In unvaccinated dairy herds, serological testing of bulk milk is a convenient method for BVDV prevalence screening. Alternatively, serological testing of young stock may indicate if BVDV is present in a herd. In BVDV positive herds, animals persistently infected (PI) with BVDV can be identified by combined use of serological and virological tests for examination of blood samples. ELISAs have been used for rapid detection of both BVDV antibodies and antigens in blood, but should preferably be backed up by other methods such as virus neutralization, virus isolation in cell cultures or amplification of viral nucleic acid. Detailed knowledge of the performance of the diagnostic tests in use, as well as of the epidemiology of bovine virus diarrhoea is essential for identification of viremic animals in affected herds.
Collapse
Affiliation(s)
- T Sandvik
- Department of Virology and Serodiagnostics, National Veterinary Institute, Oslo, Norway.
| |
Collapse
|
18
|
Letellier C, Kerkhofs P, Wellemans G, Vanopdenbosch E. Detection and genotyping of bovine diarrhea virus by reverse transcription-polymerase chain amplification of the 5' untranslated region. Vet Microbiol 1999; 64:155-67. [PMID: 10028170 PMCID: PMC7117503 DOI: 10.1016/s0378-1135(98)00267-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A reverse-transcription polymerase chain reaction (RT-PCR) was developed to differentiate the bovine diarrhea virus (BVDV) from other pestiviruses, and to determine the genotype of the BVDV isolates. For this purpose, primer pairs were selected in the 5' untranslated region (5'UTR). The primers BE and B2 were located in highly conserved regions and were pestivirus-specific. Two primer pairs named B3B4 and B5B6 were specific of BVDV genotypes I and II, respectively. With this technique, an amplification product of the expected size was obtained with either the B3B4 or the B5B6 primer pairs for the 107 BVDV isolates tested but not for BDV or CSFV. For some isolates that were grouped in the genotype II, sequence analysis of the PCR fragments confirmed their classification into this genotype.
Collapse
Affiliation(s)
- C Letellier
- Centre d'Etude et de Recherches Vétérinaires et Agrochimiques 99, Brussels, Belgium.
| | | | | | | |
Collapse
|
19
|
Muñoz DP, Lager IA, Mersich S, Zábal O, Ulloa E, Schudel AA, Weber EL. Foetal infections with bovine viral diarrhoea virus in Argentina. THE BRITISH VETERINARY JOURNAL 1996; 152:175-82. [PMID: 8680840 DOI: 10.1016/s0007-1935(96)80072-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The frequency of isolation of bovine viral diarrhoea virus (BVDV) from primary tissue cultures and organs from bovine foetuses was studied between 1992 and 1994. Around 25% of primary tissue cultures were BVDV positive. Primary testis cultures were inoculated with homogenates of spleen, kidney, lung and liver from 52 foetuses. Cells were passaged twice and BVDV antigen investigated by indirect immunofluorescence. Non-cytopathic BVDV was detected in at least one organ in 11/52 foetuses (21.2%): 6/10 spleens, 4/7 kidneys, 7/9 lungs and 3/5 livers. Cytopathic BVDV was detected in lung and kidney from two foetuses. Since only gamma-irradiated sera are used in the laboratory and only inactivated BVDV vaccines are applied in Argentina, it was concluded that these isolations represented field infections. In addition to the 11 virus positive foetuses, two foetuses were positive for BVDV antibodies, which suggested a 25% prevalence of infection. These results stress the need for disease control on a herd basis and the requirement for biological reagents of bovine origin for the detection of BVDV.
Collapse
Affiliation(s)
- D P Muñoz
- Instituto de Virología, CICV-INTA, Morón, Buenos Aires, Argentina
| | | | | | | | | | | | | |
Collapse
|
20
|
Schelp C, Greiser-Wilke I, Wolf G, Beer M, Moennig V, Liess B. Identification of cell membrane proteins linked to susceptibility to bovine viral diarrhoea virus infection. Arch Virol 1995; 140:1997-2009. [PMID: 7503697 DOI: 10.1007/bf01322688] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Three monoclonal antibodies directed against cell surface molecules of bovine cells inhibited subsequent infections with bovine viral diarrhoea virus (BVDV). They specifically blocked the infectivity of three non-cytopathogenic and three cytopathogenic BVDV strains. These results showed that an important mechanism for virus uptake was inhibited. The ligand of the monoclonal antibody BVD/CA 17, which blocked infectivity most efficiently, was found on leukocytes from a wide range of domestic and wild even-toed ungulates using flow cytometric analysis. In contrast, the monoclonal antibodies BVD/CA 26 and BVD/CA 27 appeared to be specific for bovine cells. Immunoprecipitation of labelled bovine cell surface proteins showed that the three monoclonal antibodies bound to proteins with identical relative molecular masses (M(r)). Proteins of an apparent M(r) of 93 K and 60 K were precipitated from lysates of fetal bovine kidney cells irrespectively of the MAbs used.
Collapse
Affiliation(s)
- C Schelp
- Institute of Virology, Hannover Veterinary School, Federal Republic of Germany
| | | | | | | | | | | |
Collapse
|
21
|
Bielefeldt-Ohmann H. The pathologies of bovine viral diarrhea virus infection. A window on the pathogenesis. Vet Clin North Am Food Anim Pract 1995; 11:447-76. [PMID: 8581857 PMCID: PMC7111321 DOI: 10.1016/s0749-0720(15)30461-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Pathologic lesions caused by bovine viral diarrhea virus (BVDV) infections comprise a wide spectrum of type, degree, and, by implication, pathogenesis, including congenital defects, necroticerosive lesions in mucosal epithelia and skin, and reactive as well as degenerative changes in lymphoid tissues. At least some of the pathology may not be solely due to BVDV replication per se, but rather caused by a host response to the virus, particularly the production of pro-inflammatory cytokines.
Collapse
Affiliation(s)
- H Bielefeldt-Ohmann
- Centre for Molecular Biotechnology (Arbovirology Group) School of Life Science, Queensland University of Technology, Brisbane, Australia
| |
Collapse
|
22
|
Shannon AD, Morrissy C, Mackintosh SG, Westbury HA. Detection of hog cholera virus antigens in experimentally-infected pigs using an antigen-capture ELISA. Vet Microbiol 1993; 34:233-48. [PMID: 8460468 DOI: 10.1016/0378-1135(93)90014-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
An antigen-capture ELISA was used to detect hog cholera virus (HCV) antigens in blood and tissues taken from pigs infected with 2 different strains of virus. Specific antigens were demonstrated in peripheral blood leucocytes (PBLs) and a wide range of tissue samples 4-6 days after infection of pigs with a moderate-high virulent HCV strain (Weybridge virus). Strong signal to noise (S/N) ratios were obtained in the ELISA for PBLs and lymphoid tissues such as spleen, tonsil and mesenteric lymph nodes at 5-7 days after infection with the Weybridge virus, S/N ratios varying between 8.1-19.7 for blood samples and 4.3-19.1 for spleen samples. High positive ELISA results were also obtained for duodenum and ileum samples (S/N ratios 10.3-18.6) taken from these pigs, reflecting severe pathological changes observed in the gut at post mortem. In contrast, the antigen-capture ELISA gave strong positive results for PBLs and spleen samples only at 7-9 days after infection of pigs with a low virulent strain of HCV (New South Wales virus). The ELISA S/N ratios averaged 9.5 for PBLs and 8.9 for spleen samples in these animals. Although virus isolation detected infection earlier in the infected pigs, the ELISA returned positive results on PBLs and spleen samples around the time all of the animals first showed typical signs of classical swine fever. The technique does not require tissue culture and takes less than 36 h to return a definitive result.
Collapse
Affiliation(s)
- A D Shannon
- Elizabeth Macarthur Agricultural Institute, Camden, N.S.W., Australia
| | | | | | | |
Collapse
|
23
|
Hewicker-Trautwein M, Trautwein G, Moennig V, Liess B. Infection of ovine fetal brain cell cultures with cytopathogenic and non-cytopathogenic bovine viral diarrhoea virus. Vet Microbiol 1992; 33:239-48. [PMID: 1336242 DOI: 10.1016/0378-1135(92)90052-u] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The in vitro cell tropism of non-cytopathogenic (ncp) and cytopathogenic (cp) bovine viral diarrhoea virus (BVDV) was studied in primary dissociated brain cell cultures derived from ovine fetuses of different gestational ages. The cell types infected were identified by double immunofluorescence using antibodies against BVDV and cell type-specific markers. In cultures infected with ncp BVDV viral antigen was present in neurofilament (NF 200 kDa)-positive neurons, glial fibrillary acidic protein (GFAP)-positive astrocytes and fibronectin-expressing cells. Estimation of the percentages of individual cell types infected with ncp BVDV indicated a tropism for NF 200-positive neurons. In cultures infected with cp BVD virus cytopathic changes were observed beginning at 40 hours post infection. Viral antigen was present in vacuolated NF 200-, GFAP- and fibronectin-positive cells. In comparison with non-infected control cultures a considerable reduction of the number of the different cell types was seen.
Collapse
|
24
|
Wöhrmann T, Hewicker-Trautwein M, Fernandez A, Moennig V, Liess B, Trautwein G. Distribution of bovine virus diarrhoea viral antigens in the central nervous system of cattle with various congenital manifestations. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1992; 39:599-609. [PMID: 1334302 DOI: 10.1111/j.1439-0450.1992.tb01211.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Distribution of bovine viral diarrhoea virus (BVDV) antigens in the central nervous system (CNS) of 26 cattle persistently BVDV infected, 11 cattle with mucosal disease (MD), and 32 calves with congenital brain malformations was studied using monoclonal antibodies against BVDV epitopes. In persistently infected cattle and in cattle with MD, a widespread infection of neurons was present. Predilection sites for BVDV antigens were the cerebral cortex and the hippocampus. In calves with congenital encephalopathies, viral antigen-containing neurons could only be detected in the CNS of four animals. From the topographical distribution of BVDV antigens in these four postnatal cases with end-stage lesions, no conclusions could be drawn concerning the pathogenesis of BVDV-induced encephalopathies.
Collapse
Affiliation(s)
- T Wöhrmann
- Institute of Pathology, School of Veterinary Medicine, Hannover, Germany
| | | | | | | | | | | |
Collapse
|
25
|
Abstract
The various measures of genetic variation of BVD virus was reviewed with emphasis on the implications for future control of virus-induced disease and diagnosis. While experimental data does not support unique serotypes for BVDV, there is substantial antigenic variation among the isolates examined. This variation may permit fetal infections even in animals assumed to be well vaccinated. The genetic differences between cytopathic and noncytopathic strains of BVDV are expressed in infected cells by the production of a p80 protein by cytopathic strains. In addition, cellular gene inserts have been detected in cytopathic strains. Monoclonal antibodies have demonstrated a high degree of diversity with the pestivirus population. Grouping of BVDV isolates by monoclonal antibody analysis is suggestive at best. The use of nucleic acid probes as diagnostic reagents has been compromised by the nucleic acid sequence variation found in the BVDV isolates tested.
Collapse
Affiliation(s)
- E J Dubovi
- Diagnostic Laboratory, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853
| |
Collapse
|
26
|
Haines DM, Clark EG, Dubovi EJ. Monoclonal antibody-based immunohistochemical detection of bovine viral diarrhea virus in formalin-fixed, paraffin-embedded tissues. Vet Pathol 1992; 29:27-32. [PMID: 1313612 DOI: 10.1177/030098589202900104] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Thirty-two monoclonal antibodies directed against epitopes on bovine viral diarrhea virus proteins and glycoproteins were tested for immunohistochemical reactivity with bovine viral diarrhea virus in formalin-fixed and paraffin-embedded tissues from 45 cases of bovine viral diarrhea virus-associated mucosal disease. Only one antibody, designated 15C5, which reacts with the 48-kD glycoprotein of bovine viral diarrhea virus, detected an epitope preserved in these specimens. Monoclonal antibody 15C5 and a polyclonal antibody to bovine viral diarrhea virus successfully detected bovine viral diarrhea viral antigens in 44/45 cases of mucosal disease and did not react with formalin-fixed tissues from 30 uninfected cattle. Monoclonal antibody-based immunohistochemical detection of bovine viral diarrhea virus is routinely fixed tissue specimens has advantages over other currently available techniques in terms of the convenience of specimen submission, the relative ease of method standardization, and the rapidity of the test, and by enabling identification of the virus in association with specific tissues, cell types, and histologic lesions.
Collapse
Affiliation(s)
- D M Haines
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | | | | |
Collapse
|
27
|
Liebler EM, Waschbüsch J, Pohlenz JF, Moennig V, Liess B. Distribution of antigen of noncytopathogenic and cytopathogenic bovine virus diarrhea virus biotypes in the intestinal tract of calves following experimental production of mucosal disease. ARCHIVES OF VIROLOGY. SUPPLEMENTUM 1991; 3:109-24. [PMID: 9210932 DOI: 10.1007/978-3-7091-9153-8_13] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Mucosal disease can be experimentally induced by inoculating calves persistently viremic with noncytopathogenic (ncp) Bovine Virus Diarrhea Virus (BVDV) with an antigenetically closely related cytopathogenic (cp) BVDV strain. Calves suffering from mucosal disease develop severe intestinal lesions causing breakdown of the gastrointestinal barrier and death. Knowledge about tissue distribution of ncp/cp biotypes of BVDV may contribute to the understanding of the pathogenesis of these lesions. Distribution of cpBVDV versus ncpBVDV was demonstrated in the intestinal tract of nine calves with experimentally induced mucosal disease and in five persistently viremic calves. Biotypes were distinguished immunohistochemically in organ tissues using monoclonal antibodies against marker epitopes on the viral surface glycoprotein gp53. In persistently viremic calves ncpBVDV was present in a few epithelial cells, mononuclear cells and intramural ganglia. A multifocal reaction was observed in vascular walls. In calves with mucosal disease a striking increase of antigen containing cells occurred. Viral antigen in these cells reacted with marker antibodies for cpBVDV. A distinct tissue distribution of biotypes was observed in intramural ganglia and duodenal glands. Severe tissue damage was correlated to the presence of cpBVDV antigen. This indicates the importance of cpBVDV for the development of lesions. Interactions of cpBVDV and immunemediated mechanisms will need further investigation.
Collapse
Affiliation(s)
- E M Liebler
- Institute of Pathology, Hannover Veterinary School, Federal Republic of Germany
| | | | | | | | | |
Collapse
|