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James S. Guy - One of the best experts on this subject based on the ideXlab platform.
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A Retrospective Study of Transmissible Viral Proventriculitis in Broiler Chickens in California: 2000-18.
Avian diseases, 2020Co-Authors: R. Hauck, James S. Guy, Simone T. Stoute, C. Gabriel Sentíes-cué, H. L. ShivaprasadAbstract:Transmissible viral Proventriculitis (TVP) is a disease of chickens, mostly in broilers of 2-8 wk of age. Chicken proventricular necrosis virus (CPNV), a birnavirus, is the etiologic agent. Characteristic gross lesions are enlargement, atony, and pallor of the proventriculus. Cases diagnosed in California between 2000 and 2018 (n = 477), originating from 93 different farms representing all major companies in the region, were analyzed. Frequency of cases varied widely between years, with no recognizable seasonality. The flocks were between 6 and 61 days of age; the average age was 34.0 days, and the median age was 35 days. In 166 cases, between 6.3% and 100% of the submitted birds had gross lesions in the proventriculus. The most common findings were enlarged or dilated proventriculi, thickened walls, and pale or mottled serosal appearance. Histopathologically, inflammation of the glands was the most frequent finding. Other lesions included necrosis, hyperplasia, or both conditions of the glandular epithelium; dilated glands; and occasionally fibrin deposition, fibrosis, and hemorrhages. Twenty-three proventriculi from six cases were tested by immunohistochemistry for the presence of CPNV antigen; 21 stained positive. In 209 cases, birds also had lesions in the bursa fabricii attributed to infectious bursal disease, but with no significant difference in the mean percentage of birds with gross lesions in the proventriculus between cases with or without lesions in the bursa fabricii. The results show that TVP is a common disease of broiler flocks in California and confirms that CPNV is the likely causative agent.
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Runting Stunting Syndrome Associated with Transmissible Viral Proventriculitis in Broiler Chickens
Avian diseases, 2015Co-Authors: Rute Garcia Da Noiva, James S. Guy, R. Hauck, H. L. ShivaprasadAbstract:This report describes an outbreak of transmissible viral Proventriculitis (TVP) associated with runting stunting syndrome (RSS) in 25- and 28-day-old broiler chickens, in which chicken proventricular necrosis virus (CNPV) was detected. Clinical signs included poor uniformity, very small birds for their age, increased mortality, and culling of smaller birds. Almost all birds necropsied exhibited moderate to severely enlarged proventriculi with diffusely pale serosa and thickened walls. Microscopically the proventriculi had lesions of degeneration and necrosis of the epithelium of the proventricular glands, accompanied by lymphocytic inflammation and glandular hyperplasia, with occasional formation of lymphoid nodules within the glandular parenchyma. Immunohistochemistry staining for CPNV was positive. Positive staining was generally found in the cytoplasm of glandular epithelial cells in the form of finely granular brown pigment. CPNV RNA was detected in the proventriculi by reverse transcriptase-PCR (RT-PCR). Other findings included mild enteritis in a few birds and small bursa of Fabricius. Direct electron microscopy performed on the intestinal samples was negative for viral particles. RT-PCR analysis of bursae was positive for infectious bursal disease virus (IBDV). In conclusion, this report associates TVP with RSS by describing an outbreak in which TVP attributable to CPNV was the most commonly found lesionin chickens with a clinical history compatible with RSS. Therefore, TVP should be considered as a possible differential diagnosis in cases compatible with RSS.
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Transmissible viral Proventriculitis identified in broiler breeder and layer hens.
Avian diseases, 2012Co-Authors: Rosemary A. Marusak, Melissa A. West, James F. Davis, Oscar J. Fletcher, James S. GuyAbstract:SUMMARY. Transmissible viral Proventriculitis (TVP) is a recognized cause of production losses in broiler chickens, but previously it has not been reported in broiler breeder and commercial layer hens. In this study, TVP was identified in broiler breeder and commercial layer hens, 9–20 wk of age, based on histopathologic detection of characteristic microscopic lesions. Microscopic lesions in proventriculi of affected hens consisted of glandular epithelial necrosis, ductal epithelial hyperplasia, replacement of glandular epithelium with ductal epithelium, and diffuse interstitial lymphoid infiltration. Additionally, chicken proventricular necrosis virus (CPNV), a virus previously identified as the etiology of TVP in broiler chickens, was detected in proventriculi of TVP-affected hens using a reverse transcriptase–polymerase chain reaction procedure. The findings identify TVP as a potential cause of production losses in broiler breeder and commercial layer hens and provide additional evidence for etiologic ...
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Birnavirus-associated Proventriculitis in French broiler chickens.
The Veterinary record, 2011Co-Authors: Jocelyn Marguerie, Olivier Leon, Olivier Albaric, James S. Guy, Jean-luc GuérinAbstract:TRANSMISSIBLE viral Proventriculitis (TVP) has been described sporadically in broiler chickens in the USA for decades. Clinically, this disease is characterised by impaired growth (‘runting’), poor feed conversion and limited mortality. Gross lesions are limited to enlargement and pallor of the proventriculus (Dormitorio and others 2007). In Europe, Proventriculitis in broilers was reported in 1978 in the Netherlands, but its aetiology was not determined (Kouwenhoven and others 1978). In Spain, TVP was identified and associated with infectious bursal disease virus, but the aetiology could not be determined definitively (Grau-Roma and others 2010). TVP has never been reported in France. Several viruses, including birnavirus-like ones, …
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Physical and Genomic Characteristics Identify Chicken Proventricular Necrosis Virus (R11/3 Virus) as a Novel Birnavirus
Avian diseases, 2011Co-Authors: James S. Guy, A Melissa A West, Frederick J. FullerAbstract:SUMMARY. Chicken proventricular necrosis virus (CPNV), isolate R11/3, previously was isolated from transmissible viral Proventriculitis–affected chickens and was determined to be the likely etiology of this disease. CPNV was identified as a birnavirus on the basis of virion size and morphology (icosahedral, approximately 75 nm in diameter, nonenveloped); buoyant density in cesium chloride (1.32 g/ml); a genome comprising bisegmented, double-stranded RNA (approximately 3.8 and 3.4 kilobase pairs); and nucleotide sequence analyses. Nucleotide sequencing of CPNV RNA, segment B, identified a single large open reading frame that encodes a 903–amino acid protein. The 903–amino acid protein was identified as the putative VP1, the viral RNA-dependent RNA polymerase (RdRp), on the basis of sequence homologies with other birnavirus VP1 proteins. The CPNV VP1 possessed the unique permuted RdRp sequence motif arrangement characteristic of birnaviruses; however, phylogenetic analyses based on VP1 demonstrated that CPN...
Natàlia Majó - One of the best experts on this subject based on the ideXlab platform.
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Retrospective study on transmissible viral Proventriculitis and chicken proventricular necrosis virus (CPNV) in the UK.
Avian pathology : journal of the W.V.P.A, 2019Co-Authors: Llorenç Grau-roma, Simone De Brot, Miquel Nofrarías, Alex Schock, N Wali, Aline Padilha De Fraga, Cristina Garcia-rueda, Natàlia MajóAbstract:Chicken proventricular necrosis virus (CPNV) is a recently described birnavirus, which has been proposed to be the cause of transmissible viral Proventriculitis (TVP). The understanding of the epidemiology of both the virus and the disease is very limited. A retrospective investigation on TVP and CPNV in broiler chicken submissions from the UK from between 1994 and 2015 was performed with the aims of assessing the longitudinal temporal evolution of TVP and CPNV, and to review the histological proventricular lesions in the studied chickens. Ninety-nine of the 135 included submissions (73.3%) fulfilled the TVP-diagnostic criteria, while the remaining 36 submissions (26.7%) displayed only lymphocytic Proventriculitis (LP). The first detection of CPNV by PCR dated from 2009. Results showed a rise in the number of both TVP and positive CPNV RT-PCR submissions from 2009 with a peak in 2013, suggesting that they may be an emerging or re-emerging disease and pathogen, respectively. Twenty-two out of the 99 submissions displaying TVP lesions (22%) and four out of the 36 (11%) submissions with LP gave positive CPNV RT-PCR results, further supporting the association between CPNV and TVP and confirming that CPNV is present in a low proportion of proventriculi that do not fulfil the TVP-diagnostic criteria. In addition, intranuclear inclusion bodies were observed in 22 of the submissions with TVP. The vast majority of these cases (21 of 22, 96%) gave negative CPNV RT-PCR results, raising the question of whether a virus other than CPNV is responsible for some of these TVP-affected cases.RESEARCH HIGHLIGHTSTVP and CPNV have been present in British broilers since at least 1994 and 2009, respectively.TVP and CPNV seem to be an emerging and re-emerging disease and pathogen, respectively.CPNV was detected in proventriculi with both TVP and LP-lesions.Viruses other than CPNV may be responsible for some TVP-affected cases.
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Detection of transmissible viral Proventriculitis and chicken proventricular necrosis virus in the UK
Avian pathology : journal of the W.V.P.A, 2016Co-Authors: Llorenç Grau-roma, Kirsty Reid, Simone De Brot, Richard Jennison, Paul A. Barrow, Raúl Sánchez, Miquel Nofrarías, Michael Clark, Natàlia MajóAbstract:Increasing evidence suggests that a new birnavirus, named Chicken proventricular necrosis virus (CPNV), is the aetiological agent of transmissible viral Proventriculitis (TVP). The present work aimed to explore the possible presence of both TVP and CPNV in the UK. Forty-four chickens showing TVP-compatible gross lesions were classified into 3 groups based on the histological lesions: i) TVP-affected chickens: lymphocytic infiltration and glandular necrosis (n=15); ii) lymphocytic Proventriculitis (LP)-affected chickens: lymphocytic infiltration without necrosis (n=18); and iii) without Proventriculitis (WP): no lymphocytic infiltration or necrosis (n=11). Nine proventriculi (7 out of 15 corresponding to TVP, and 2 out of 11 corresponding to LP) were positive for CPNV by RT-PCR. These results support the previously suggested idea of CPNV as causative agent of TVP. Moreover, this data shows that CPNV can also be detected in a number of cases with LP, which do not fulfil the histological TVP criteria. Phylogenetic analysis of partial sequences of gene VP1 showed that British CPNV sequences were closer to other European CPNV sequences and might constitute a different lineage from the American CPNV. TVP cases with negative CPNV PCR results may be due to chronic stages of the disease or to the reduced PCR sensitivity on formalin-fixed paraffin embedded tissues. However, involvement of other agents in some of the cases cannot totally be ruled out. As far as the authors are aware, this is the first peer-reviewed report of TVP as well as of CPNV in the UK, and the first exploratory CPNV phylogenetic study.
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Infectious bursal disease-like virus in cases of transmissible viral Proventriculitis.
The Veterinary record, 2010Co-Authors: Llorenç Grau-roma, Alberto Marco, Jorge Martínez, Aida J Chaves, Roser Dolz, Natàlia MajóAbstract:TRANSMISSIBLE viral Proventriculitis (TVP) is an infectious disease of chickens that results in an enlarged and fragile proventriculus. The disease is characterised by specific microscopic lesions that include glandular epithelial (oxynticopeptic) cell necrosis, ductal epithelial hyperplasia, and
Majó Natàlia - One of the best experts on this subject based on the ideXlab platform.
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Retrospective study on transmissible viral Proventriculitis and chicken proventricular necrosis virus (CPNV) in the UK
'Informa UK Limited', 2020Co-Authors: Grau-roma Llorenc, De Brot Simone, Nofrarías Miquel, Schock Alex, Wali, Nabil Ali, De Fraga, Aline Padilha, Garcia-rueda Cristina, Majó NatàliaAbstract:Chicken proventricular necrosis virus (CPNV) is a recently described birnavirus, which has been proposed to be the cause of transmissible viral Proventriculitis (TVP). The understanding of the epidemiology of both the virus and the disease is very limited. A retrospective investigation on TVP and CPNV in broiler chicken submissions from the UK from between 1994 and 2015 was performed with the aims of assessing the longitudinal temporal evolution of TVP and CPNV, and to review the histological proventricular lesions in the studied chickens. Ninety-nine of the 135 included submissions (73.3%) fulfilled the TVP-diagnostic criteria, while the remaining 36 submissions (26.7%) displayed only lymphocytic Proventriculitis (LP). The first detection of CPNV by PCR dated from 2009. Results showed a rise in the number of both TVP and positive CPNV RT-PCR submissions from 2009 with a peak in 2013, suggesting that they may be an emerging or re-emerging disease and pathogen, respectively. Twenty-two out of the 99 submissions displaying TVP lesions (22%) and four out of the 36 (11%) submissions with LP gave positive CPNV RT-PCR results, further supporting the association between CPNV and TVP and confirming that CPNV is present in a low proportion of proventriculi that do not fulfil the TVP-diagnostic criteria. In addition, intranuclear inclusion bodies were observed in 22 of the submissions with TVP. The vast majority of these cases (21 of 22, 96%) gave negative CPNV RT-PCR results, raising the question of whether a virus other than CPNV is responsible for some of these TVP-affected cases.RESEARCH HIGHLIGHTSTVP and CPNV have been present in British broilers since at least 1994 and 2009, respectively.TVP and CPNV seem to be an emerging and re-emerging disease and pathogen, respectively.CPNV was detected in proventriculi with both TVP and LP-lesions.Viruses other than CPNV may be responsible for some TVP-affected cases.info:eu-repo/semantics/acceptedVersio
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Detection of transmissible viral Proventriculitis (TVP) and Chicken proventricular necrosis virus (CPNV) in the United Kingdom
'Informa UK Limited', 2017Co-Authors: Grau-roma Llorenc, Reid Kirsty, De Brot Simone, Jennison Richard, Barrow Paul, Sánchez Raúl, Nofrarías Miquel, Clark Mike, Majó NatàliaAbstract:Increasing evidence suggests that a new birnavirus, named Chicken proventricular necrosis virus (CPNV), is the aetiological agent of transmissible viral Proventriculitis (TVP). The present work aimed to explore the possible presence of both TVP and CPNV in the UK. Forty-four chickens showing TVP-compatible gross lesions were classified into 3 groups based on the histological lesions: i) TVP-affected chickens: lymphocytic infiltration and glandular necrosis (n=15); ii) lymphocytic Proventriculitis (LP)-affected chickens: lymphocytic infiltration without necrosis (n=18); and iii) without Proventriculitis (WP): no lymphocytic infiltration or necrosis (n=11). Nine proventriculi (7 out of 15 corresponding to TVP, and 2 out of 11 corresponding to LP) were positive for CPNV by RT-PCR. These results support the previously suggested idea of CPNV as causative agent of TVP. Moreover, this data shows that CPNV can also be detected in a number of cases with LP, which do not fulfil the histological TVP criteria. Phylogenetic analysis of partial sequences of gene VP1 showed that British CPNV sequences were closer to other European CPNV sequences and might constitute a different lineage from the American CPNV. TVP cases with negative CPNV PCR results may be due to chronic stages of the disease or to the reduced PCR sensitivity on formalin-fixed paraffin embedded tissues. However, involvement of other agents in some of the cases cannot totally be ruled out. As far as the authors are aware, this is the first peer-reviewed report of TVP as well as of CPNV in the UK, and the first exploratory CPNV phylogenetic study
Grau-roma Llorenc - One of the best experts on this subject based on the ideXlab platform.
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Retrospective study on transmissible viral Proventriculitis and chicken proventricular necrosis virus (CPNV) in the UK
'Informa UK Limited', 2020Co-Authors: Grau-roma Llorenc, De Brot Simone, Nofrarías Miquel, Schock Alex, Wali, Nabil Ali, De Fraga, Aline Padilha, Garcia-rueda Cristina, Majó NatàliaAbstract:Chicken proventricular necrosis virus (CPNV) is a recently described birnavirus, which has been proposed to be the cause of transmissible viral Proventriculitis (TVP). The understanding of the epidemiology of both the virus and the disease is very limited. A retrospective investigation on TVP and CPNV in broiler chicken submissions from the UK from between 1994 and 2015 was performed with the aims of assessing the longitudinal temporal evolution of TVP and CPNV, and to review the histological proventricular lesions in the studied chickens. Ninety-nine of the 135 included submissions (73.3%) fulfilled the TVP-diagnostic criteria, while the remaining 36 submissions (26.7%) displayed only lymphocytic Proventriculitis (LP). The first detection of CPNV by PCR dated from 2009. Results showed a rise in the number of both TVP and positive CPNV RT-PCR submissions from 2009 with a peak in 2013, suggesting that they may be an emerging or re-emerging disease and pathogen, respectively. Twenty-two out of the 99 submissions displaying TVP lesions (22%) and four out of the 36 (11%) submissions with LP gave positive CPNV RT-PCR results, further supporting the association between CPNV and TVP and confirming that CPNV is present in a low proportion of proventriculi that do not fulfil the TVP-diagnostic criteria. In addition, intranuclear inclusion bodies were observed in 22 of the submissions with TVP. The vast majority of these cases (21 of 22, 96%) gave negative CPNV RT-PCR results, raising the question of whether a virus other than CPNV is responsible for some of these TVP-affected cases.RESEARCH HIGHLIGHTSTVP and CPNV have been present in British broilers since at least 1994 and 2009, respectively.TVP and CPNV seem to be an emerging and re-emerging disease and pathogen, respectively.CPNV was detected in proventriculi with both TVP and LP-lesions.Viruses other than CPNV may be responsible for some TVP-affected cases.info:eu-repo/semantics/acceptedVersio
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Detection of transmissible viral Proventriculitis (TVP) and Chicken proventricular necrosis virus (CPNV) in the United Kingdom
'Informa UK Limited', 2017Co-Authors: Grau-roma Llorenc, Reid Kirsty, De Brot Simone, Jennison Richard, Barrow Paul, Sánchez Raúl, Nofrarías Miquel, Clark Mike, Majó NatàliaAbstract:Increasing evidence suggests that a new birnavirus, named Chicken proventricular necrosis virus (CPNV), is the aetiological agent of transmissible viral Proventriculitis (TVP). The present work aimed to explore the possible presence of both TVP and CPNV in the UK. Forty-four chickens showing TVP-compatible gross lesions were classified into 3 groups based on the histological lesions: i) TVP-affected chickens: lymphocytic infiltration and glandular necrosis (n=15); ii) lymphocytic Proventriculitis (LP)-affected chickens: lymphocytic infiltration without necrosis (n=18); and iii) without Proventriculitis (WP): no lymphocytic infiltration or necrosis (n=11). Nine proventriculi (7 out of 15 corresponding to TVP, and 2 out of 11 corresponding to LP) were positive for CPNV by RT-PCR. These results support the previously suggested idea of CPNV as causative agent of TVP. Moreover, this data shows that CPNV can also be detected in a number of cases with LP, which do not fulfil the histological TVP criteria. Phylogenetic analysis of partial sequences of gene VP1 showed that British CPNV sequences were closer to other European CPNV sequences and might constitute a different lineage from the American CPNV. TVP cases with negative CPNV PCR results may be due to chronic stages of the disease or to the reduced PCR sensitivity on formalin-fixed paraffin embedded tissues. However, involvement of other agents in some of the cases cannot totally be ruled out. As far as the authors are aware, this is the first peer-reviewed report of TVP as well as of CPNV in the UK, and the first exploratory CPNV phylogenetic study
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Més a prop de determinar el virus causant de la Proventriculitis transmissible dels pollastres
2011Co-Authors: Majó Masferrer I Natàlia, Grau-roma LlorencAbstract:La Proventriculitis vírica transmissible (PVT) és una malaltia infecciosa que afecta els pollastres, causant un increment del gruix i una major fragilitat de l'estómac glandular (proventricle). La malaltia es caracteritza per lesions microscòpiques específiques que inclouen necrosi de les cèl·lules glandulars epitelials (cèl·lules oxíntico-pèptiques), hiperplàsia dels conductes epitelials i inflamació limfocítica. Són diversos els agents virals que han estat suggerits com a possibles causants de la malaltia. Entre ells destaquen el virus de la bronquitis infecciosa (BIV), un virus semblant a un adenovirus (família de virus que infecten tant humans com animals), i el virus de la malaltia de Gumboro (conegut en anglès com a infectious bursal disease virus, IBDV), que afecta només pollastres. En qualsevol cas, no s'ha confirmat que cap d'aquests agents fos el causant de la malaltia. Aquest estudi, realitzat per investigadors de la UAB, inclou la primera descripció de detecció intralesional d'un agent infecciós en casos de pollastres afectats naturalment de Proventriculitis vírica transmissible
Andrzej Koncicki - One of the best experts on this subject based on the ideXlab platform.
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Transmissible Viral Proventriculitis Caused by Chicken ProVentricular Necrosis Virus Displaying Serological Cross-Reactivity with IBDV.
Animals : an open access journal from MDPI, 2020Co-Authors: Marcin Śmiałek, Michał Gesek, Daria Dziewulska, Jowita Samanta Niczyporuk, Andrzej KoncickiAbstract:Transmissible viral Proventriculitis (TVP) of chickens is manifested in decreased body weight gains, poor feed conversion and weight diversity. Although TVP etiology has not been defined, a Birnaviridae family member, named chicken proventricular necrosis virus (CPNV) is considered as a potential factor of a disease. This study was undertaken in order to reproduce TVP and to evaluate its etiology. Broiler chickens of the TVP-infected group were inoculated with TVP positive proventriculi homogenate on the 24th day of life. Samples were collected, on infection day and 14 days post-infection (dpi). The 14 dpi anatomo- and histopathological evaluation, revealed that we have succeeded to reproduce TVP. TVP-infected birds gained 30.38% less body weight. In the TVP-infected group a seroconversion against picornaviruses, fowl adenoviruses (FAdV) and infectious bursal disease viruses (IBDV) was recorded with an ELISA test. Using RT-PCR and PCR, CPNV was detected in proventriculi and FAdV in spleens and livers of infected birds, 14 dpi. Our study supports that CPNV is involved in the development of TVP. We did not record the presence of IBDV in TVP or control birds, despite our recording of a seroconversion against IBDV in TVP infected birds. CPNV and IBDV belong to the same family, which allows us to assume serological cross-reactivity between them. The role of FAdV needs further evaluation.
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Chicken proventricular necrosis virus related transmissible viral Proventriculitis in broiler chickens in Poland
2020Co-Authors: Marcin Śmiałek, Michał Gesek, Daria Dziwulska, Jowita Samanta-niczyporuk, Andrzej KoncickiAbstract:Abstract Background. Transmissible viral Proventriculitis (TVP) is an infectious disease reported in all production types of chickens. TVP is manifested in decreased body weight gains, wide weight diversity of birds in the flock and poor feed conversion. Histopathological examination seems to be the most reliable method for confirming the disease. Although TVP etiology has not been explicitly defined, a novel virus identified as a member of the Birnaviridae family, named chicken proventricular necrosis virus (CPNV) has been isolated from clinical cases of TVP and it is now considered as a potential factor of a disease. The study was undertaken in order to reproduce the disease under laboratory conditions and to evaluate the etiology of first described Polish case of TVP. Results. Anatomopathological and histopathological evaluation reveled that we've succeeded to reproduce TVP in broiler chickens. Within 14 days after infection birds gained approximately 30,38% less body weight in comparison to Control group. In TVP infected group a seroconversion against FAdV and IBDV was recorded 14 days post infection (dpi). 14 dpi CPNV was detected in proventriculi, while FAdV in spleens and livers of infected birds. Conclusions. We have demonstrated that CPNV was involved in the development of the disease. We did not record the presence of IBDV in the TVP or control birds, despite our recording a strong seroconversion against IBDV in the birds from the TVP group. CPNV belongs to the same family as IBDV, which allows us to assume serological cross-reactivity between them. This possibility of CPNV infections affecting IBDV antibody levels detected by commonly available ELISAs should be taken into account under poultry field conditions and diagnosis. The role of FAdV in the development of TVP needs further evaluation.
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Identification of Transmissible Viral Proventriculitis (TVP) in broiler chickens in Poland.
Polish journal of veterinary sciences, 2017Co-Authors: Marcin Śmiałek, Michał Gesek, A. Śmiałek, Andrzej KoncickiAbstract:The aim of the study was to investigate the possibility of Transmissible Viral Proventriculitis (TVP) occurrence in broiler chickens in Poland. In march 2016 proventriculi samples were collected from broiler chickens showing poor uniformity and decreased body weight, accompanied by enlarged proventriculi. Histopathological examination of affected proventriculi revealed typical lesions associated with TVP (vacuolar degeneration and necrosis of glandular epithelium, replacement of glandular epithelium by hyperplastic ductal epithelium and moderate to severe lymphocytic infiltration). To our best knowledge, up to date there is no report indicating the presence of TVP in Poland nor in Central and Eastern Europe.
