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Kirchner M, Miller WG, Osborne JA, Badgley B, Neidermeyer J, Kathariou S. Campylobacter Colonization and Diversity in Young Turkeys in the Context of Gastrointestinal Distress and Antimicrobial Treatment. Microorganisms 2023; 11:microorganisms11020252. [PMID: 36838217 PMCID: PMC9963665 DOI: 10.3390/microorganisms11020252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/10/2023] [Accepted: 01/11/2023] [Indexed: 01/21/2023] Open
Abstract
Young turkeys are vulnerable to undifferentiated gastrointestinal distress, including "irritable and crabby syndrome" (ICS), which compromises flock performance and is typically treated with a combination of penicillin and gentamicin (P/G). However, the effects of ICS and P/G treatment on Campylobacter remain poorly understood. We investigated the impact of ICS and P/G treatment on Campylobacter levels and diversity in four flocks from three turkey farms. Cecum and jejunum samples were analyzed weekly from day of hatch to week 4-5. All four flocks became colonized with multidrug resistant (MDR) Campylobacter jejuni and C. coli by week 2-3, and two developed ICS. ICS and P/G treatment did not significantly impact total Campylobacter levels or strain genotypes but impacted species and antimicrobial resistance (AMR) profiles. One flock was raised under antibiotic-free (ABF) conditions while another flock at the same farm was raised conventionally. The ABF flock did not develop ICS while its counterpart did. However, Campylobacter strains, AMR profiles and sequence types were generally shared between these two flocks. Our findings suggest that ICS and P/G treatment impacted Campylobacter population dynamics in commercial young turkey flocks, and that ABF flocks may become readily colonized by MDR strains from non-ABF flocks at the same farm.
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Affiliation(s)
- Margaret Kirchner
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - William G. Miller
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, US Department of Agriculture, Albany, CA 94710, USA
| | - Jason A. Osborne
- Department of Statistics, North Carolina State University, Raleigh, NC 27695, USA
| | - Brian Badgley
- School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Jeffrey Neidermeyer
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Sophia Kathariou
- Department of Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Raleigh, NC 27695, USA
- Correspondence:
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Tang J, Fu M, Chen X, Zhao Y, Gao L, Cao H, Li X, Zheng SJ, Wang Y. Arrest of Cell Cycle by Avian Reovirus p17 through Its Interaction with Bub3. Viruses 2022; 14:v14112385. [PMID: 36366482 PMCID: PMC9693402 DOI: 10.3390/v14112385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/25/2022] [Accepted: 10/25/2022] [Indexed: 01/31/2023] Open
Abstract
Avian reoviruses (ARV) are a group of poultry pathogens that cause runting and stunting syndrome (RSS), a condition otherwise known as "frozen chicken", which are characterized by dramatically delayed growth in broilers. It has been known that p17, a nonstructural protein encoded by ARV, prohibits cellular proliferation by halting the cell cycle at the G2/M phase, the result of which is directly associated with the typical clinical sign of RSS. Nevertheless, the mechanism by which p17 modulates cell-cycle progression remains largely unknown. Here, we screened the interactome of ectopically expressed p17 through a yeast two-hybrid assay and identified Bub3, a cellular mitotic checkpoint protein, as a binding partner of p17. The infection of the Vero cells by ARV downregulated the Bub3 expression, while the knockdown of Bub3 alleviated the p17-modulated cell-cycle arrest during ARV infection. Remarkably, the suppression of Bub3 by RNAi in the Vero cells significantly reduced the viral mRNA and protein abundance, which eventually led to diminished virus replication. Altogether, our findings reveal that ARV p17 impedes host cell proliferation through a Bub3-dependent cell-cycle arrest, which eventually contributes to efficient virus replication. These results also unveil a hitherto unknown therapeutic target for RSS.
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Affiliation(s)
- Junyu Tang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Mengjiao Fu
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Xiang Chen
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Yimeng Zhao
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Li Gao
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Hong Cao
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Xiaoqi Li
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Shijun J. Zheng
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Yongqiang Wang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing 100193, China
- College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
- Correspondence: ; Tel./Fax: +86-(10)-6273-3026
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Cloft SE, Kinstler SR, Reno KE, Sellers HS, Franca M, Ecco R, Lee MD, Maurer JJ, Wong EA. Runting Stunting Syndrome in Broiler Chickens Is Associated with Altered Intestinal Stem Cell Morphology and Gene Expression. Avian Dis 2022; 66:85-94. [DOI: 10.1637/21-00109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/20/2021] [Indexed: 11/09/2022]
Affiliation(s)
- Sara E. Cloft
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061
| | - Sydney R. Kinstler
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061
| | - Kaitlyn E. Reno
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061
| | - Holly S. Sellers
- Department of Population Health, Poultry Diagnostic Research Center, University of Georgia, Athens, GA 30601
| | - Monique Franca
- Department of Population Health, Poultry Diagnostic Research Center, University of Georgia, Athens, GA 30601
| | - Roselene Ecco
- Department of Clinic and Surgery, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 30123-970, Brazil
| | - Margie D. Lee
- Department of Biomedical Science and Pathobiology, Virginia Tech, Blacksburg, VA 24061
| | - John J. Maurer
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061
| | - Eric A. Wong
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061
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4
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Ramsubeik S, Jerry C, Crossley B, Armién AG, Rejmanek D, Pitesky M, Shivaprasad H, Stoute S. Analysis of Diagnostic Cases of Turkey Viral Enteritis in Commercial Turkey Poults in California. J APPL POULTRY RES 2022. [DOI: 10.1016/j.japr.2022.100238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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5
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Courtillon C, Briand FX, Allée C, Contrant M, Beven V, Lucas P, Blanchard Y, Mouchel S, Eterradossi N, Delforterie Y, Grasland B, Brown P. Description of the first isolates of guinea fowl corona and picornaviruses obtained from a case of guinea fowl fulminating enteritis. Avian Pathol 2021; 50:507-521. [PMID: 34545751 DOI: 10.1080/03079457.2021.1976725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Guinea fowl fulminating enteritis has been reported in France since the 1970s. In 2014, a coronavirus was identified and appeared as a possible viral pathogen involved in the disease. In the present study, intestinal content from a guinea fowl involved in a new case of the disease in 2017 was analysed by deep sequencing, revealing the presence of a guinea fowl coronavirus (GfCoV) and a picornavirus (GfPic). Serial passage assays into the intra-amniotic cavity of 13-day-old specific pathogen-free chicken eggs and 20-day-old conventional guinea fowl eggs were attempted. In chicken eggs, isolation assays failed, but in guinea fowl eggs, both viruses were successfully obtained. Furthermore, two GfCoV and two GfPic isolates were obtained from the same bird but from different sections of its intestines. This shows that using eggs of the same species, in which the virus has been detected, can be the key for successful isolation. The consensus sequence of the full-length genomes of both GfCoV isolates was highly similar, and correlated to those previously described in terms of genome organization, ORF length and phylogenetic clustering. According to full-length genome analysis and the structure of the Internal Ribosome Entry Site, both GfPic isolates belong to the Anativirus genus and specifically the species Anativirus B. The availability of the first isolates of GfCoV and GfPic will now provide a means of assessing their pathogenicity in guinea fowl in controlled experimental conditions and to assess whether they are primary viral pathogens of the disease "guinea fowl fulminating enteritis".RESEARCH HIGHLIGHTSFirst isolation of guinea fowl coronaviruses and picornaviruses.Eggs homologous to the infected species are key for isolation.Isolates available to precisely evaluate the virus roles in fulminating enteritis.First full-length genome sequences of guinea fowl picornaviruses.
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Affiliation(s)
- Céline Courtillon
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | - François-Xavier Briand
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | - Chantal Allée
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | - Maud Contrant
- GVB Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | - Véronique Beven
- GVB Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | - Pierrick Lucas
- GVB Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | - Yannick Blanchard
- GVB Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | | | - Nicolas Eterradossi
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | | | - Béatrice Grasland
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
| | - Paul Brown
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané-Niort Ploufragan, France
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6
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Shehata AA, Basiouni S, Sting R, Akimkin V, Hoferer M, Hafez HM. Poult Enteritis and Mortality Syndrome in Turkey Poults: Causes, Diagnosis and Preventive Measures. Animals (Basel) 2021; 11:ani11072063. [PMID: 34359191 PMCID: PMC8300142 DOI: 10.3390/ani11072063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/02/2021] [Accepted: 07/06/2021] [Indexed: 11/19/2022] Open
Abstract
Simple Summary The poult enteritis and mortality syndrome (PEMS) causes severe economic losses in turkeys. Several agents were described to be associated with the PEMS; however, a specific etiological agent(s) has not been identified. The diagnosis of PEMS is still a huge challenge for several reasons: (1) no specific clinical signs or pathognomonic lesions, (2) isolation of some enteric viruses still difficult, (3) the pathogenicity of several enteric viruses in turkeys is not fully understood, (4) PEMS is an interaction between several known and might be unknown agents and (5) opportunistic microorganisms also have a role in the pathogenesis of PEMS. Both electron microscopy and molecular techniques can be used for diagnosis of PEMS and might help to discover unknown causes. Until now, no specific vaccines against enteric viruses associated with PEMS. However, biosecurity, maintaining a healthy gut and strengthening the immune system of turkey poults using probiotics, prebiotics and/or phytogenic substances are crucial factors to prevent and/or reduce losses of PEMS in turkeys. This review is a call for scientists to perform further research to investigate the real cause(s) of PEMS and to develop a preventive strategy against it. Abstract Poult enteritis and mortality syndrome (PEMS) is one of the most significant problem affecting turkeys and continues to cause severe economic losses worldwide. Although the specific causes of PEMS remains unknown, this syndrome might involve an interaction between several causative agents such as enteropathogenic viruses (coronaviruses, rotavirus, astroviruses and adenoviruses) and bacteria and protozoa. Non-infectious causes such as feed and management are also interconnected factors. However, it is difficult to determine the specific cause of enteric disorders under field conditions. Additionally, similarities of clinical signs and lesions hamper the accurate diagnosis. The purpose of the present review is to discuss in detail the main viral possible causative agents of PEMS and challenges in diagnosis and control.
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Affiliation(s)
- Awad A. Shehata
- Birds and Rabbit Medicine Department, Faculty of Veterinary Medicine, University of Sadat City, Sadat City 32897, Egypt
- Research and Development Section, PerNaturam GmbH, 56290 Gödenroth, Germany
- Correspondence: (A.A.S.); (H.M.H.)
| | - Shereen Basiouni
- Clinical Pathology Department, Faculty of Veterinary Medicine, Benha University, Benha 13518, Egypt;
| | - Reinhard Sting
- Chemisches und Veterinäruntersuchungsamt Stuttgart, 70736 Fellbach, Germany; (R.S.); (V.A.)
| | - Valerij Akimkin
- Chemisches und Veterinäruntersuchungsamt Stuttgart, 70736 Fellbach, Germany; (R.S.); (V.A.)
| | - Marc Hoferer
- Chemisches und Veterinäruntersuchungsamt Freiburg, 79108 Freiburg, Germany;
| | - Hafez M. Hafez
- Institute of Poultry Diseases, Faculty of Veterinary Medicine, Free University of Berlin, 14163 Berlin, Germany
- Correspondence: (A.A.S.); (H.M.H.)
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7
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de Oliveira LB, Stanton JB, Zhang J, Brown C, Butt SL, Dimitrov K, Afonso CL, Volkening JD, Lara LJC, de Oliveira CSF, Ecco R. Runting and Stunting Syndrome in Broiler Chickens: Histopathology and Association With a Novel Picornavirus. Vet Pathol 2020; 58:123-135. [PMID: 33280540 DOI: 10.1177/0300985820969971] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Runting stunting syndrome (RSS) in commercial chickens has been reported worldwide, and although several studies have attempted to clarify the cause and describe the lesions, there are gaps in knowledge of the epidemiology, pathogenesis, and etiology. The study objective was to use commercial chicks naturally affected by RSS to describe the histologic changes of RSS in all segments of the small intestine in chicks of different ages and to identify viral gene sequences in affected chicks and their association with histologic lesions. Chicks lacking clinical signs but from the same houses and from unaffected houses were used as controls. The average weight of affected chicks was significantly lower than expected for their flocks. Macroscopically, the small intestines had paler serosa, with watery, mucoid, or foamy contents and poorly digested food. Histologic lesions were characterized by necrotic crypts, crypt dilation, and flattening of the crypt epithelium. Histomorphometry of the intestines revealed villous atrophy especially in the jejunum and ileum. Histologic changes in other organs were not observed. Random next-generation sequencing of total RNA extracted from formalin-fixed paraffin-embedded tissues detected avian nephritis virus, avian rotavirus, and picornavirus in jejunal segments from 7-day-old chicks. No viruses were detected in the jejunum of 1-day-old chicks. Detection of picornaviral reads was significantly associated (P < .05) with histologic lesions of RSS. Sequence analysis of the picornavirus revealed genetic similarity with the genus Gallivirus. Using in situ hybridization for galliviral nucleic acid sequences, the signal was associated with crypt lesion severity, although signal was detected both in chicks with and without RSS.
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Affiliation(s)
| | | | - Jian Zhang
- 1355University of Georgia, Athens, GA, USA
| | | | | | - Kiril Dimitrov
- 57776Southeast Poultry Research Laboratory, US National Poultry Research Center, Agricultural Research Service, USDA, Athens, GA, USA.,117328Texas A&M Veterinary Medical Diagnostic Laboratory, College Station, TX, USA
| | - Claudio L Afonso
- 57776Southeast Poultry Research Laboratory, US National Poultry Research Center, Agricultural Research Service, USDA, Athens, GA, USA
| | | | | | | | - Roselene Ecco
- 28114Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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Fletcher OJ, Mansell R, Martin MP, Borst LB, Barnes HJ, Gonzalez LM. Gross Morphometry, Histomorphometry, and Immunohistochemistry Confirm Early and Persistent Jejunal Crypt Hyperplasia in Poults with Enteritis and Depressed Growth. Avian Dis 2019; 62:163-170. [PMID: 29944394 DOI: 10.1637/11759-101717-reg.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Phosphorylated histone 3 (PH3) and cleaved caspase 3 (CCASP3) were used to detect proliferating and apoptotic cells, respectively, in the jejunums of female sibling poults, with and without enteritis and depressed growth, from hatch to day 35. Poults that developed enteritis and depressed growth (SIB flock) were raised on a commercial farm in eastern North Carolina, whereas poults with normal growth and no enteritis (TAU flock) were raised in the Teaching Animal Unit at North Carolina State University College of Veterinary Medicine. Beginning on day 5 through day 35 and at processing, TAU poults were significantly heavier than SIB poults. Jejunal weights, relative jejunal weights, and jejunal densities were greater in SIB poults from day 10 through 35. Jejunal efficiency (body weight /jejunal length) was higher in TAU poults at day 5 and days 10 through 35. Mucosal thickness was greater in SIB poults between days 7 and 21 but greater in TAU poults at days 28 and 35. From day 7 to 35, villus-to-crypt ratios were higher for TAU poults and lower for SIB poults because hyperplastic crypts formed a greater percentage of the mucosa in SIB poults. By day 7, PH3- and CCASP3-positive cells were increased in SIB poults, showing that mucosal changes resulted from combined crypt epithelial hyperplasia and increased apoptosis of villous enterocytes. Findings in this study confirm that enteritis, in the absence of clinical signs, and depressed growth in turkey poults begins by day 7, can be identified microscopically, persists for at least 35 days, is associated with lower processing weights, and has a profound negative effect on turkey growth.
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Affiliation(s)
- O J Fletcher
- A Department of Population Health & Pathobiology, College of Veterinary Medicine, NC State University, 1060 William Moore Dr., Raleigh, NC 27607
| | - R Mansell
- A Department of Population Health & Pathobiology, College of Veterinary Medicine, NC State University, 1060 William Moore Dr., Raleigh, NC 27607
| | - M P Martin
- A Department of Population Health & Pathobiology, College of Veterinary Medicine, NC State University, 1060 William Moore Dr., Raleigh, NC 27607
| | - L B Borst
- A Department of Population Health & Pathobiology, College of Veterinary Medicine, NC State University, 1060 William Moore Dr., Raleigh, NC 27607
| | - H John Barnes
- A Department of Population Health & Pathobiology, College of Veterinary Medicine, NC State University, 1060 William Moore Dr., Raleigh, NC 27607
| | - L M Gonzalez
- B Department of Clinical Sciences, College of Veterinary Medicine, NC State University, 1060 William Moore Dr., Raleigh, NC 27607
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9
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Brown PA, Courtillon C, Weerts EAWS, Andraud M, Allée C, Vendembeuche A, Amelot M, Rose N, Verheije MH, Eterradossi N. Transmission Kinetics and histopathology induced by European Turkey Coronavirus during experimental infection of specific pathogen free turkeys. Transbound Emerg Dis 2018; 66:234-242. [PMID: 30146717 PMCID: PMC7138094 DOI: 10.1111/tbed.13006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/14/2018] [Accepted: 08/18/2018] [Indexed: 12/15/2022]
Abstract
Numerous viruses, mostly in mixed infections, have been associated worldwide with poult enteritis complex (PEC). In 2008 a coronavirus (Fr‐TCoV 080385d) was isolated in France from turkey poults exhibiting clinical signs compatible with this syndrome. In the present study, the median infectious dose (ID50), transmission kinetics and pathogenicity of Fr‐TCoV were investigated in 10‐day‐old SPF turkeys. Results revealed a titre of 104.88ID50/ml with 1 ID50/ml being beyond the limit of genome detection using a well‐characterized qRT‐PCR for avian coronaviruses. Horizontal transmission of the virus via the airborne route was not observed however, via the oro‐faecal route this proved to be extremely rapid (one infectious individual infecting another every 2.5 hr) and infectious virus was excreted for at least 6 weeks in several birds. Histological examination of different zones of the intestinal tract of the Fr‐TCoV‐infected turkeys showed that the virus had a preference for the lower part of the intestinal tract with an abundance of viral antigen being present in epithelial cells of the ileum, caecum and bursa of Fabricius. Viral antigen was also detected in dendritic cells, monocytes and macrophages in these areas, which may indicate a potential for Fr‐TCoV to replicate in antigen‐presenting cells. Together these results highlight the importance of good sanitary practices in turkey farms to avoid introducing minute amounts of virus that could suffice to initiate an outbreak, and the need to consider that infected individuals may still be infectious long after a clinical episode, to avoid virus dissemination through the movements of apparently recovered birds.
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Affiliation(s)
- Paul A Brown
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France.,EPICOREM Consortium, Unité de Recherche Risques Microbiens (U2RM), Université de Caen, Caen, France
| | - Céline Courtillon
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France.,EPICOREM Consortium, Unité de Recherche Risques Microbiens (U2RM), Université de Caen, Caen, France
| | - Erik A W S Weerts
- Faculty of Veterinary Medicine, Department of Pathobiology, Utrecht University, Utrecht, Netherlands
| | - Mathieu Andraud
- EBEP Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France
| | - Chantal Allée
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France.,EPICOREM Consortium, Unité de Recherche Risques Microbiens (U2RM), Université de Caen, Caen, France
| | - Anthony Vendembeuche
- SELEAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France
| | - Michel Amelot
- SELEAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France
| | - Nicolas Rose
- EBEP Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France
| | - Monique H Verheije
- Faculty of Veterinary Medicine, Department of Pathobiology, Utrecht University, Utrecht, Netherlands
| | - Nicolas Eterradossi
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Bretagne Loire, Ploufragan, France.,EPICOREM Consortium, Unité de Recherche Risques Microbiens (U2RM), Université de Caen, Caen, France
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10
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Dhama K, Gowthaman V, Karthik K, Tiwari R, Sachan S, Kumar MA, Palanivelu M, Malik YS, Singh RK, Munir M. Haemorrhagic enteritis of turkeys - current knowledge. Vet Q 2017; 37:31-42. [PMID: 28024457 DOI: 10.1080/01652176.2016.1277281] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Haemorrhagic enteritis virus (HEV), an adenovirus associated with acute haemorrhagic gastro-intestinal disease of 6-11-week old turkeys predominantly hampers both humoral and cellular immunity. Affected birds are more prone to secondary complications (e.g. colibacillosis and clostridiosis) and failure to mount an effective vaccine-induced immune response. HEV belongs to the new genus Siadenovirus. Feco-oral transmission is the main route of entry of the virus and it mainly colonizes bursa, intestine and spleen. Both naturally occurring virulent and avirulent strains of HEVs are serologically indistinguishable. Recent findings revealed that ORF1, E3 and fib genes are the key factors affecting virulence. The adoption of suitable diagnostic tools, proper vaccination and biosecurity measures have restrained the occurrence of disease epidemics. For diagnostic purposes, the best source of HEV is either intestinal contents or samples from spleen. For rapid detection highly sensitive and specific tests such as quantitative real-time PCR based on Taq man probe has been designed. Avirulent strains of HEV or MSDV can be effectively used as live vaccines. Novel vaccines include recombinant hexon protein-based subunit vaccines or recombinant virus-vectored vaccines using fowl poxvirus (FPV) expressing the native hexon of HEV. Notably, subunit vaccines and recombinant virus vectored vaccines altogether offer high protection against challenge or field viruses. Herein, we converse a comprehensive analysis of the HEV genetics, disease pathobiology, advancements in diagnosis and vaccination along with appropriate prevention and control strategies.
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Affiliation(s)
- Kuldeep Dhama
- a Avian Diseases Section, Division of Pathology , ICAR-Indian Veterinary Research Institute , Izatnagar , India
| | - Vasudevan Gowthaman
- b Poultry Disease Diagnosis and Surveillance Laboratory , Veterinary College and Research Institute , Namakkal , Tamil Nadu, India
| | - Kumaragurubaran Karthik
- c Central University Laboratory, Tamil Nadu Veterinary and Animal Sciences University , Chennai , India
| | - Ruchi Tiwari
- d Department of Microbiology , DUVASU , Mathura , India
| | - Swati Sachan
- a Avian Diseases Section, Division of Pathology , ICAR-Indian Veterinary Research Institute , Izatnagar , India
| | - M Asok Kumar
- a Avian Diseases Section, Division of Pathology , ICAR-Indian Veterinary Research Institute , Izatnagar , India
| | - M Palanivelu
- a Avian Diseases Section, Division of Pathology , ICAR-Indian Veterinary Research Institute , Izatnagar , India
| | - Yashpal Singh Malik
- e Division of Biological Standardization , ICAR-Indian Veterinary Research Institute , Izatnagar , India
| | - Raj Kumar Singh
- f Director, ICAR-Indian Veterinary Research Institute , Izatnagar , India
| | - Muhammad Munir
- g Avian Viral Diseases Programme Compton Laboratory , Berkshire , UK
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Domańska-Blicharz K, Bocian Ł, Lisowska A, Jacukowicz A, Pikuła A, Minta Z. Cross-sectional survey of selected enteric viruses in Polish turkey flocks between 2008 and 2011. BMC Vet Res 2017; 13:108. [PMID: 28410608 PMCID: PMC5391614 DOI: 10.1186/s12917-017-1013-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 03/30/2017] [Indexed: 11/10/2022] Open
Abstract
Background Enteric diseases are an important health problem for the intensive poultry industry, resulting in considerable economic losses. Apart from such microbiological agents associated with enteritis as bacteria and parasites, a lot of research has been recently conducted on viral origin of enteric diseases. However, enteric viruses have been identified in intestinal tract of not only diseased but also healthy poultry, so their role in enteritis is still unclear. The present study aimed at determination of the prevalence of four enteric viruses, namely astrovirus, coronavirus, parvovirus and rotavirus in meat-type turkey flocks in Poland as well as at statistical evaluation of the occurrence of the studied viruses and their relationships with the health status and the age of birds. Two hundred and seven flocks of birds aged 1-20 weeks originating from different regions of the country were investigated between 2008 and 2011. Clinical samples (10 individual faecal swabs/flock) were duly processed and examined using molecular methods targeting the conservative regions of viral genomes: RNA-dependent RNA polymerase gene of astrovirus, non-structural 1 gene of parvovirus, non-structural protein 4 gene of rotavirus, and 5′ untranslated region fragment of turkey coronavirus. Different statistical methods (i.e. the independence chi-square test, the correspondence analysis and the logistic regression model) were used to establish any relationships between the analyzed data. Results Overall, 137 (66.2%, 95% CI: 59.3-72.6) of the 207 turkey flocks sampled were infected with one or more enteric viruses. Among the 137 flocks, 74 (54%, 95% CI: 45.3-62.6) were positive for one virus, whereas 54 (39.4%, 9 5% CI: 31.2-48.1) and 9 (6.6%, 95% CI: 3.1-12.1) were co-infected with two or three different enteric viruses, respectively. No flock was simultaneously infected with all four viruses studied. The prevalence of astrovirus infection was 44.9% (95% CI: 38.0-52.0), parvovirus 27.5% (95% CI: 21.6-34.2), rotavirus 18.8% (95% CI: 13.8-24.8), and coronavirus 9.7% (95% CI: 6.0-14.5). Young turkeys aged 1-4 weeks old had the highest (82.1%, 95% CI:71.7-89.8) prevalence of viral infection. Applied statistical methods have indicated the dependence of rotavirus infection as well as the co-infection with multiple viruses and the health status of turkeys. Furthermore, our results statistically confirm that especially young birds are susceptible to infection with rotavirus and astrovirus. Conclusions The study demonstrated the presence of astrovirus, coronavirus, parvovirus and rotavirus infections in Polish turkey farms. These viruses were detected in both healthy and diseased birds. However, the presented results provide valuable feedback which could help to evaluate the role of some enteric viruses in the etiology of enteritis in turkey.
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Affiliation(s)
- K Domańska-Blicharz
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantów 57, 24-100, Puławy, Poland.
| | - Ł Bocian
- Department of Epidemiology and Risk Assessment, National Veterinary Research Institute, Al. Partyzantów 57, 24-100, Puławy, Poland
| | - A Lisowska
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantów 57, 24-100, Puławy, Poland
| | - A Jacukowicz
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantów 57, 24-100, Puławy, Poland
| | - A Pikuła
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantów 57, 24-100, Puławy, Poland
| | - Z Minta
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantów 57, 24-100, Puławy, Poland
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Falcone E, Busi C, Lavazza A, Monini M, Bertoletti M, Canelli E, Vignolo E, Ruggeri FM, Boniotti MB. Molecular characterization of avian rotaviruses circulating in Italian poultry flocks. Avian Pathol 2016; 44:509-15. [PMID: 26399154 DOI: 10.1080/03079457.2015.1096011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Avian rotaviruses are still largely undefined despite being widespread in several avian species and despite the economic impact of rotavirus (RV) enteritis in poultry flocks. In this study, the presence of different avian RV groups was investigated in commercial poultry flocks reared in Northern and Central Italy and with a history of enteric diseases. Faeces or intestinal contents from different avian species previously found to contain RV particles by electron microscopy (EM) were analysed by both RNA-polyacrylamide gel electrophoresis and reverse transcription-polymerase chain reaction specific for groups A, D, F and G RVs. Group D avian RV was detected in 107 of 117 samples tested (91.5%), whereas groups A, F and G avian RVs were present in 70 (59%), 61 (52.1%) and 31 (26.5%) samples, respectively. Multiple presence of different RV groups was detected in 83% of samples. This study provides novel data on the prevalence of genetically different avian RVs in Italian poultry flocks. This information is useful to elucidate the epidemiology of avian RVs circulating in Italy.
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Affiliation(s)
- Emiliana Falcone
- a Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare , Istituto Superiore di Sanità , Viale Regina Elena 299, 00161 Roma , Italy
| | - Chiara Busi
- b Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna , Via Antonio Bianchi, 7/9, 25124 Brescia , Italy
| | - Antonio Lavazza
- b Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna , Via Antonio Bianchi, 7/9, 25124 Brescia , Italy
| | - Marina Monini
- a Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare , Istituto Superiore di Sanità , Viale Regina Elena 299, 00161 Roma , Italy
| | - Marco Bertoletti
- b Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna , Via Antonio Bianchi, 7/9, 25124 Brescia , Italy
| | - Elena Canelli
- b Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna , Via Antonio Bianchi, 7/9, 25124 Brescia , Italy
| | - Edoardo Vignolo
- a Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare , Istituto Superiore di Sanità , Viale Regina Elena 299, 00161 Roma , Italy
| | - Franco Maria Ruggeri
- a Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare , Istituto Superiore di Sanità , Viale Regina Elena 299, 00161 Roma , Italy
| | - Maria Beatrice Boniotti
- b Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna , Via Antonio Bianchi, 7/9, 25124 Brescia , Italy
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13
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Day JM, Zsak L. Molecular Characterization of Enteric Picornaviruses in Archived Turkey and Chicken Samples from the United States. Avian Dis 2016; 60:500-5. [PMID: 27309295 DOI: 10.1637/11289-092415-resnote] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Recent metagenomic analyses of the enteric viromes in turkeys and chickens have revealed complex viral communities comprised of multiple viral families. Of particular significance are the novel avian picobirnaviruses (family Picobirnaviridae), multiple genera of tailed phages (family Siphoviridae), and undescribed avian enteric picornaviruses (family Picornaviridae). In addition to these largely undescribed-and therefore relatively poorly understood-poultry enteric viral families, these metagenomic analyses have also revealed the presence of well-known groups of enteric viruses such as the chicken and turkey astroviruses (family Astroviridae) and the avian rotaviruses and reoviruses (family Reoviridae). The order Picornavirales is a group of viruses in flux, particularly among the avian picornaviruses, since several new genera have been described recently based upon community analysis of enteric viromes from poultry and other avian species worldwide. Our previous investigation of the turkey enteric picornaviruses suggests the avian enteric picornaviruses may contribute to the enteric disease syndromes and performance problems often observed in turkeys in the Southeastern United States. This report describes our recent phylogenetic analysis of turkey and chicken enteric samples archived at the Southeast Poultry Research Laboratory from 2004 to present and is a first step in placing these novel avian picornaviruses within the larger Picornaviridae family.
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Affiliation(s)
- J Michael Day
- A USDA/ARS, U.S. National Poultry Research Center, Southeast Poultry Research Laboratory, 934 College Station Road, Athens, GA 30605
| | - Laszlo Zsak
- A USDA/ARS, U.S. National Poultry Research Center, Southeast Poultry Research Laboratory, 934 College Station Road, Athens, GA 30605
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14
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Mundt E, Collett SR, Berghaus R, Pedroso AA, Lee MD, Maurer JJ. Can Bacteriotherapy Using Commercially Available Probiotics, Prebiotics, and Organic Acids Ameliorate the Symptoms Associated With Runting-Stunting Syndrome in Broiler Chickens? Avian Dis 2015; 59:201-6. [PMID: 26473669 DOI: 10.1637/122013-reg] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Runting-stunting syndrome (RSS) in poultry has been known for more than 40 years, but the precise etiology remains unknown and a licensed vaccine is consequently not currently available. In order to mitigate the symptoms associated with RSS, a series of experiments was performed to investigate whether a combined bacteriotherapeutic treatment consisting of probiotics, prebiotics, and organic acids could influence the outcome of this disease. Initially two groups of commercial broiler chickens were either left uninoculated or inoculated with filtrate from homogenized intestines of RSS-affected broiler chickens. One group from each of these two challenge groups was treated, with a bacteriotherapeutic regimen. After 12 days chickens were euthanatized, the body weight was measured, and duodenal lesions were enumerated. Five consecutive broiler chicken flocks were then raised either on litter from RSS-affected birds or on fresh wood shavings. Treatment had no beneficial effect on the number and severity of intestinal lesions. There appeared to be a significant build-up of RSS agent(s) in poultry litter, with each consecutive flock placement, independent of bacteriotherapeutic treatment, as more individuals exhibited intestinal lesions on built-up litter in RSS-affected houses (28.9% vs. 44%). While treatment did not appear to consistently reduce intestinal lesions, it did significantly improve the mean body weights (P<0.05) and uniformity of 12-day-old chickens placed on reused litter in houses in which RSS-infected birds were previously raised. A combination of litter management and bacteriotherapy may be needed to ameliorate the adverse effects of RSS on intestinal health and body weight in broiler chickens.
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Affiliation(s)
- E Mundt
- A Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, 953 College Station Road, Athens, GA 30602-4875.,B Current address: Boehringer-Ingelheim Veterinary Research Center, Bemeroder Str. 31, D-30559 Hannover, Germany
| | - S R Collett
- A Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, 953 College Station Road, Athens, GA 30602-4875
| | - R Berghaus
- C Department of Population Health, University of Georgia, Athens, GA 30602
| | - A A Pedroso
- A Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, 953 College Station Road, Athens, GA 30602-4875
| | - M D Lee
- A Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, 953 College Station Road, Athens, GA 30602-4875
| | - J J Maurer
- A Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, 953 College Station Road, Athens, GA 30602-4875
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15
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Brown PA, Touzain F, Briand FX, Gouilh AM, Courtillon C, Allée C, Lemaitre E, De Boisséson C, Blanchard Y, Eterradossi N. First complete genome sequence of European turkey coronavirus suggests complex recombination history related with US turkey and guinea fowl coronaviruses. J Gen Virol 2015; 97:110-120. [PMID: 26585962 PMCID: PMC7081074 DOI: 10.1099/jgv.0.000338] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A full-length genome sequence of 27 739 nt was determined for the only known European turkey coronavirus (TCoV) isolate. In general, the order, number and size of ORFs were consistent with other gammacoronaviruses. Three points of recombination were predicted, one towards the end of 1a, a second in 1b just upstream of S and a third in 3b. Phylogenetic analysis of the four regions defined by these three points supported the previous notion that European and American viruses do indeed have different evolutionary pathways. Very close relationships were revealed between the European TCoV and the European guinea fowl coronavirus in all regions except one, and both were shown to be closely related to the European infectious bronchitis virus (IBV) Italy 2005. None of these regions of sequence grouped European and American TCoVs. The region of sequence containing the S gene was unique in grouping all turkey and guinea fowl coronaviruses together, separating them from IBVs. Interestingly the French guinea fowl virus was more closely related to the North American viruses. These data demonstrate that European turkey and guinea fowl coronaviruses share a common genetic backbone (most likely an ancestor of IBV Italy 2005) and suggest that this recombined in two separate events with different, yet related, unknown avian coronaviruses, acquiring their S-3a genes. The data also showed that the North American viruses do not share a common backbone with European turkey and guinea fowl viruses; however, they do share similar S-3a genes with guinea fowl virus.
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Affiliation(s)
- P A Brown
- EPICOREM Consortium, Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France.,VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, BP 53-22440 Ploufragan, France
| | - F Touzain
- VB Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, G, BP 53-22440 Ploufragan, France
| | - F X Briand
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, BP 53-22440 Ploufragan, France.,EPICOREM Consortium, Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France
| | - A M Gouilh
- EPICOREM Consortium, Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France.,Institut Pasteur, Environment and Infectious Risks Research and Expertise Unit, 25-28 rue du Docteur Roux, F-75724 Paris Cedex 15, France.,Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France
| | - C Courtillon
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, BP 53-22440 Ploufragan, France.,EPICOREM Consortium, Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France
| | - C Allée
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, BP 53-22440 Ploufragan, France.,EPICOREM Consortium, Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France
| | - E Lemaitre
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, BP 53-22440 Ploufragan, France.,EPICOREM Consortium, Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France
| | - C De Boisséson
- VB Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, G, BP 53-22440 Ploufragan, France
| | - Y Blanchard
- VB Unit, Agence Nationale de Sécurité Sanitaire (Anses), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, G, BP 53-22440 Ploufragan, France
| | - N Eterradossi
- VIPAC Unit, Agence Nationale de Sécurité Sanitaire (ANSES), Laboratoire de Ploufragan-Plouzané, Université Européenne de Bretagne, BP 53-22440 Ploufragan, France.,EPICOREM Consortium, Université de Caen, Unité de Recherche Risques Microbiens (U2RM), F-14000 Caen, France
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16
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Awe OO, Kang KI, Ibrahim M, Ali A, Elaish M, Saif YM, Lee CW. Age-Related Susceptibility of Turkeys to Enteric Viruses. Avian Dis 2015; 59:207-12. [DOI: 10.1637/10907-071514-reg] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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17
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Zsak L, Cha RM, Li F, Day JM. Host Specificity and Phylogenetic Relationships of Chicken and Turkey Parvoviruses. Avian Dis 2015; 59:157-61. [DOI: 10.1637/10939-092414-resnote] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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18
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Day JM, Oakley BB, Seal BS, Zsak L. Comparative analysis of the intestinal bacterial and RNA viral communities from sentinel birds placed on selected broiler chicken farms. PLoS One 2015; 10:e0117210. [PMID: 25635690 PMCID: PMC4311960 DOI: 10.1371/journal.pone.0117210] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 12/21/2014] [Indexed: 12/28/2022] Open
Abstract
There is a great deal of interest in characterizing the complex microbial communities in the poultry gut, and in understanding the effects of these dynamic communities on poultry performance, disease status, animal welfare, and microbes with human health significance. Investigations characterizing the poultry enteric virome have identified novel poultry viruses, but the roles these viruses play in disease and performance problems have yet to be fully characterized. The complex bacterial community present in the poultry gut influences gut development, immune status, and animal health, each of which can be an indicator of overall performance. The present metagenomic investigation was undertaken to provide insight into the colonization of specific pathogen free chickens by enteric microorganisms under field conditions and to compare the pre-contact intestinal microbiome with the altered microbiome following contact with poultry raised in the field. Analysis of the intestinal virome from contact birds ("sentinels") placed on farms revealed colonization by members of the Picornaviridae, Picobirnaviridae, Reoviridae, and Astroviridae that were not present in pre-contact birds or present in proportionally lower numbers. Analysis of the sentinel gut bacterial community revealed an altered community in the post-contact birds, notably by members of the Lachnospiracea/Clostridium and Lactobacillus families and genera. Members of the avian enteric Reoviridae and Astroviridae have been well-characterized and have historically been implicated in poultry enteric disease; members of the Picobirnaviridae and Picornaviridae have only relatively recently been described in the poultry and avian gut, and their roles in the recognized disease syndromes and in poultry performance in general have not been determined. This metagenomic analysis has provided insight into the colonization of the poultry gut by enteric microbes circulating in commercial broiler flocks, and has identified enteric viruses and virus communities that warrant further study in order to understand their role(s) in avian gut health and disease.
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Affiliation(s)
- J. Michael Day
- United States Department of Agriculture, Agricultural Research Service, Southeast Poultry Research Laboratory, Athens, GA, United States of America
| | - Brian B. Oakley
- United States Department of Agriculture, Agricultural Research Service, Poultry Microbiological Safety Research Unit, Athens, GA, United States of America
| | - Bruce S. Seal
- United States Department of Agriculture, Agricultural Research Service, Poultry Microbiological Safety Research Unit, Athens, GA, United States of America
| | - Laszlo Zsak
- United States Department of Agriculture, Agricultural Research Service, Southeast Poultry Research Laboratory, Athens, GA, United States of America
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19
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Detection of Astrovirus, Coronavirus and Haemorrhagic Enteritis Virus in Turkeys with Poult Enteritis Mortality Syndrome in Turkey. J Poult Sci 2015. [DOI: 10.2141/jpsa.0150021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Abstract
A previous metagenomic analysis of the turkey gut RNA virus community identified novel enteric viruses that may play roles in poultry enteric diseases or in performance problems noted in the field. As part of the molecular characterization of these novel enteric viruses, a reverse transcriptase-PCR diagnostic assay was developed, targeting a novel turkey-origin picobirnavirus (PBV) initially identified in a pooled intestinal sample from turkey poults in North Carolina. Little detailed molecular information exists regarding the family Picobirnaviridae, particularly for the PBVs that have been described in avian species. This diagnostic assay targets the turkey PBV RNA-dependent RNA polymerase gene and produces an 1135-bp amplicon. This assay was validated using in vitro transcribed RNA and was tested using archived enteric samples collected from turkey flocks in the southeastern United States. Further, a phylogenetic analysis suggests the turkey PBV is unique because it does not group closely with the recognized PBV genogroups circulating in mammalian hosts.
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Abstract
Gut health is very important to get maximum returns in terms of weight gain and egg production. Enteric diseases such as poult enteritis complex (PEC) in turkeys do not allow their production potential to be achieved to its maximum. A number of viruses, bacteria, and protozoa have been implicated but the primary etiology has not been definitively established. Previously, electron microscopy was used to detect the presence of enteric viruses, which were identified solely on the basis of their morphology. With the advent of rapid molecular diagnostic methods and next generation nucleic acid sequencing, researchers have made long strides in identification and characterization of viruses associated with PEC. The molecular techniques have also helped us in identification of pathogens which were previously not known. Regional and national surveys have revealed the presence of several different enteric viruses in PEC including rotavirus, astrovirus, reovirus and coronavirus either alone or in combination. There may still be unknown pathogens that may directly or indirectly play a role in enteritis in turkeys. This review will focus on the role of turkey coronavirus, rotavirus, reovirus, and astrovirus in turkey enteritis.
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Awe OO, Ali A, Elaish M, Ibrahim M, Murgia M, Pantin-Jackwood M, Saif YM, Lee CW. Effect of Coronavirus Infection on Reproductive Performance of Turkey Hens. Avian Dis 2013; 57:650-6. [DOI: 10.1637/10502-012513-reg.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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24
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Abstract
Previously we identified a novel parvovirus from enteric contents of chickens that were affected by enteric diseases. Comparative sequence analysis showed that the chicken parvovirus (ChPV) represented a new member in the Parvoviridae family. Here, we describe some of the pathogenic characteristics of ChPV in young broilers. Following experimental infection, 2-day-old broiler chickens showed characteristic signs of enteric disease. Runting-stunting syndrome (RSS) was observed in four of five experimental groups with significant growth retardation between 7 and 28 days postinoculation (DPI). Viral growth in small intestine and shedding was detected at early times postinoculation, which was followed by viremia and generalization of infection. ChPV could be detected in most of the major tissues for 3 to 4 wk postinoculation. Immunohistochemistry staining revealed parvovirus-positive cells in the duodenum of inoculated birds at 7 and 14 DPI. Our data indicate that ChPV alone induces RSS in broilers and is important determinant in the complex etiology of enteric diseases of poultry.
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Affiliation(s)
- Laszlo Zsak
- Southeast Poultry Research Laboratory, U.S. Department of Agriculture, Agricultural Research Service, Athens, GA 30605. USA.
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Guionie O, Courtillon C, Allee C, Maurel S, Queguiner M, Eterradossi N. An experimental study of the survival of turkey coronavirus at room temperature and +4°C. Avian Pathol 2013; 42:248-52. [PMID: 23607441 PMCID: PMC7154299 DOI: 10.1080/03079457.2013.779364] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Turkey coronavirus (TCoV) is a gammacoronavirus (Coronaviridae, Nidovirales) responsible for digestive disorders in young turkeys. TCoV has been associated with poult enteritis complex, a syndrome that severely affects turkey production. No medical prophylaxis exists to control TCoV, therefore sanitary measures such as cleaning and disinfection are essential. It is thus important to evaluate temperatures that allow persistence of TCoV in the environment. Two series of aliquots of a suspension of a French isolate of TCoV (Fr TCoV) were stored at room temperature or +4°C for 0 to 40 days. As TCoV does not grow in cell culture, the presence of residual infectious TCoV in the stored samples was tested by inoculating embryonated specific pathogen free turkey eggs. As TCoV does not induce lesions in the embryo, virus replication in the jejunum and ileum of the embryos was detected 4 days post inoculation, using RNA extraction and a real-time reverse transcriptase-polymerase chain reaction based on the nucleocapsid gene. No surviving virus was detected after 10 days storage at +21.6±1.4°C or after 40 days storage at +4.1±1.6°C, these temperatures being representative of the mean summer and winter temperatures, respectively, in the major French poultry-producing region. The relatively short survival of the virus at room temperature should contribute to limited virus survival during summer months. However, infectious virus was still detected after 20 days storage at the cooler temperatures, a finding that suggests prolonged survival of Fr TCoV and easier transmission between poultry farms in a cool environment are possible.
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Affiliation(s)
- Olivier Guionie
- Anses-French Agency for Food, Environmental and Occupational Health Safety, Avian and Rabbit Virology, Immunology and Parasitology Unit, Ploufragan, France European University of Brittany UEB.
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26
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Jindal N, Chander Y, Patnayak DP, Mor SK, Ziegler AF, Goyal SM. A multiplex RT-PCR for the detection of astrovirus, rotavirus, and reovirus in turkeys. Avian Dis 2012; 56:592-6. [PMID: 23050480 DOI: 10.1637/9958-100911-resnote.1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This study was undertaken to develop and validate a multiplex reverse transcription-polymerase chain reaction (mRT-PCR) for simultaneous detection of avian rotavirus, turkey astrovirus-2 (TAstV-2), and avian reovirus. Primers targeting the conserved regions of NSP4 gene of avian rotavirus, polymerase gene of TAstV-2, and S4 gene of avian reovirus were used. The position of bands at 630, 802, and 1120 base pairs on agarose gel confirmed the presence of rotavirus, TAstV-2, and reovirus, respectively. This mRT-PCR was found to be specific as no amplification was observed with avian influenza virus, Newcastle disease virus, turkey coronavirus, avian metapneumovirus, and intestinal contents of uninfected turkey poults. Intestinal contents of poults from flocks suspected of exhibiting "poult enteritis syndrome" were pooled and tested. Of the 120 pooled samples tested, 70% were positive for TAstV-2, 45% for avian rotavirus, and 18% for avian reovirus. These three viruses were detected alone or in different combinations. Of the samples tested, 20% were negative for these three viruses, 38% were positive for a single virus (TAstV or rotavirus or reovirus), and 42% were positive for two or three viruses. This single-tube mRT-PCR assay has the potential to serve as a rapid diagnostic method for the simultaneous detection of the three enteric viruses in turkeys.
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Affiliation(s)
- Naresh Jindal
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, 1333 Gortner Avenue, Saint Paul, MN 55108, USA
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Abstract
Avian astroviruses comprise a diverse group of viruses affecting many avian species and causing enteritis, hepatitis, and nephritis. To date, six different astroviruses have been identified in avian species based on the species of origin and viral genome characteristics: two turkey-origin astroviruses [Turkey Astrovirus type 1 (TAstV-1) and type 2 (TAstV-2)]; two chicken-origin astroviruses [Avian Nephritis Virus (ANV) and Chicken Astrovirus (CAstV)]; and two duck-origin astrovirus [Duck Astrovirus type 1 (DAstV-1) and type 2 (DAstV-2)]. ANV has also been detected in turkeys, ducklings, pigeons, and guinea fowl; and TAstrovirus-2-like viruses have also been found in guinea fowl. Astroviruses are commonly associated with enteric disease syndromes in poultry including runting-stunting syndrome of broilers (RSS), poult enteritis complex or syndrome (PEC or PES), poult enteritis mortality syndrome (PEMS), and enteritis in guinea fowl. The molecular characterization of the different avian astroviruses shows great genetic variability among each type, and this variability influences the ability to detect these viruses by molecular and serological techniques. In this chapter, we review the different aspects related to avian astroviruses, including molecular biology, pathogenesis, diagnosis, and control.
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Affiliation(s)
- Stacey Schultz-Cherry
- , Infectious Diseases, St Jude Children’s Research Hospital, 262 Danny Thomas Place, Memphis, 38105 Tennessee USA
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Domanska-Blicharz K, Jacukowicz A, Lisowska A, Minta Z. Genetic characterization of parvoviruses circulating in turkey and chicken flocks in Poland. Arch Virol 2012; 157:2425-30. [PMID: 23011307 PMCID: PMC3506198 DOI: 10.1007/s00705-012-1446-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 07/04/2012] [Indexed: 11/25/2022]
Abstract
Between 2008 and 2011, commercial turkey and chicken flocks in Poland were examined for the presence of turkey parvovirus (TuPV) and chicken parvovirus (ChPV). Clinical samples (10 individual faecal swabs/flock) from 197 turkey flocks (turkeys aged 1 to 19 weeks) and 45 chicken flocks (chickens aged 3 to 17 weeks) were collected in different regions of the country and tested using a PCR assay that targeted the NS1 gene (3’ORF). The prevalence of TuPV was 29.4 % in the flocks tested, while ChPV infections were found in 22.2 % of the studied flocks. Phylogenetic analysis revealed a clear division into three groups: ChPV-like, TuPV-like and a third, previously unrecognized and distinct subgroup, TuPV-LUB, containing exclusively three Polish isolates from turkeys. The isolates from the novel group showed as little as 50.6-64.5 % of nucleotide sequence identity to the prototype chicken and turkey parvovirus strains. Genetic analysis of a ChPV isolate that was classified in the TuPV group strongly suggests a recombination event between chicken and turkey parvoviruses.
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Affiliation(s)
- Katarzyna Domanska-Blicharz
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantow 57, 24-100 Pulawy, Poland.
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Mor SK, Abin M, Costa G, Durrani A, Jindal N, Goyal SM, Patnayak DP. The role of type-2 turkey astrovirus in poult enteritis syndrome. Poult Sci 2012; 90:2747-52. [PMID: 22080013 PMCID: PMC7195392 DOI: 10.3382/ps.2011-01617] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An experimental study was conducted to determine the comparative pathogenicity of type-2 turkey astrovirus (TAstV-2) obtained from turkey flocks afflicted with poult enteritis syndrome (PES) and from turkey flocks displaying no apparent signs of infection. In total, ninety 7-d-old poults, which tested negative for the presence of astrovirus, rotavirus, coronavirus, and reovirus by reverse transcriptase (RT) PCR, were divided evenly into 3 groups: A, B, and C. Birds in group A were inoculated orally with turkey astrovirus-positive intestinal contents from birds affected with PES. Group B received turkey astrovirus-containing intestinal contents from apparently healthy flocks. Group C served as a negative control and was given PBS. Clinical signs of diarrhea, depression, and dullness were observed in group A. Birds in group B also showed clinical signs similar to those in group A, although the signs were milder in nature. Birds in group C did not show any clinical signs. At 16 d postinoculation, the BW of birds in group A was significantly lower than that of birds in groups B or C. In addition, the bursa size was reduced in group A, but not in groups B or C. Birds in groups A and B, but not in group C, were found to shed turkey astrovirus in their feces, as detected by RT-PCR. These results provide a preliminary indication that TAstV-2 from PES birds may be more pathogenic than TAstV-2 from apparently healthy poults. Further studies are needed to determine if pathogenic and nonpathogenic strains of TAstV-2 exist in the environment. These results also reinforce our previous observations that astrovirus is involved in PES, causing significant retardation in growth and weight gain.
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Affiliation(s)
- S K Mor
- Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN, USA
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Palade EA, Demeter Z, Hornyák A, Nemes C, Kisary J, Rusvai M. High prevalence of turkey parvovirus in turkey flocks from Hungary experiencing enteric disease syndromes. Avian Dis 2011; 55:468-75. [PMID: 22017049 DOI: 10.1637/9688-021711-resnote.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Samples collected in 2008 and 2009, from 49 turkey flocks of 6 to 43 days in age and presenting clinical signs of enteric disease and high mortality, were tested by polymerase chain reaction and reverse transcription-polymerase chain reaction for the presence of viruses currently associated with enteric disease (ED) syndromes: astrovirus, reovirus, rotavirus, coronavirus, adenovirus, and parvovirus. Turkey astroviruses were found in 83.67% of the cases and turkey astrovirus 2 (TAst-2) in 26.53%. The investigations directly demonstrated the high prevalence of turkey parvovirus (TuPV) in 23 flocks (46.9%) experiencing signs of ED, making this pathogen the second most identified after astroviruses. Phylogenetic analysis on a 527 base pair-long region from the NS1 gene revealed two main clusters, a chicken parvovirus (ChPV) and a TuPV group, but also the presence of a divergent branch of tentatively named "TuPV-like ChPV" strains. The 23 Hungarian TuPV strains were separately positioned in two groups from the American origin sequences in the TuPV cluster. An Avail-based restriction fragment length polymorphism assay has also been developed for the quick differentiation of TuPV, ChPV, and divergent TuPV-like ChPV strains. As most detected enteric viruses have been directly demonstrated in healthy turkey flocks as well, the epidemiology of this disease complex remains unclear, suggesting that a certain combination of pathogens, environmental factors, or both are necessary for the development of clinical signs.
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Affiliation(s)
- Elena Alina Palade
- Department of Pathology and Forensic Veterinary Medicine, Faculty of Veterinary Science, Szent István University, 1078 Budapest, István utca 2, Hungary.
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Pantin-Jackwood MJ, Strother KO, Mundt E, Zsak L, Day JM, Spackman E. Molecular characterization of avian astroviruses. Arch Virol 2010; 156:235-44. [PMID: 21069394 DOI: 10.1007/s00705-010-0849-z] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Accepted: 10/21/2010] [Indexed: 10/18/2022]
Abstract
Astroviruses are frequently associated with enteric diseases in poultry, being isolated from cases of runting-stunting syndrome (RSS) of broiler chickens, poult enteritis complex (PEC), and poult enteritis mortality syndrome (PEMS) of turkeys. Currently, five types of avian astrovirus have been identified: turkey astroviruses 1 and 2 (TAstV-1, TAstV-2), avian nephritis virus (ANV), chicken astrovirus (CAstV) and duck astrovirus (DAstV). The objective of this study was to molecularly characterize the different types of avian astroviruses circulating in commercial poultry. Sequence analysis of a region of ORF2, which encodes the capsid precursor protein associated with serotype and viral pathogenesis, revealed extensive variation in amino acid sequence within each subtype: TAstV-2 (81.5%-100%), ANV (69.9%-100%), and CAstV (85.3%-97.9%). However, this region was more conserved in TAstV-1's (96.2%-100%). Furthermore, a novel astrovirus was detected in chicken samples and found to be <64% similar to ANV and <30.6% similar to CAstV. The results of this study underline the great genetic variability of avian astroviruses and indicate that there are most likely multiple serotypes of each avian astrovirus circulating in commercial poultry.
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Affiliation(s)
- M J Pantin-Jackwood
- Southeast Poultry Research Laboratory, Agricultural Research Laboratory, U.S. Department of Agriculture, 934 College Station Road, Athens, GA 30605, USA.
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Gomaa MH, Yoo D, Ojkic D, Barta JR. Infection with a pathogenic turkey coronavirus isolate negatively affects growth performance and intestinal morphology of young turkey poults in Canada. Avian Pathol 2010; 38:279-86. [PMID: 19937512 DOI: 10.1080/03079450903055389] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Turkey coronavirus (TCoV) is an important viral pathogen causing diarrhoea of young turkey poults that is associated with sizeable economic losses for the turkey industry. Using a field isolate that was found to be free from turkey astrovirus and avian reovirus we were able to reproduce the clinical disease associated with TCoV. Clinical signs and weight gain of poults during experimental infections were compared with age-matched, uninfected controls. Poults infected at 2 days of age had 100% morbidity and 10% mortality, and birds infected at 28 days of age showed 75% morbidity and no mortality. Diarrhoea was consistently seen in infected poults at 2 to 3 days post infection (d.p.i.) with a duration of about 3 to 5 days. Mean body weights of birds infected at 2 or 28 days of age were significantly reduced compared with uninfected birds by 7 d.p.i. and remained significantly lower for the duration of the study. At 44 days of age, poults infected at 2 or 28 days of age weighed only 68.1% or 77.7%, respectively, compared with uninfected turkeys of the same age on the same diet, a mean difference in body weights of 683 or 477g, respectively. Infected birds had profound villus atrophy with some compensatory crypt hyperplasia at 5 to 7 d.p.i. Villus heights in the duodenum were significantly reduced at 7 d.p.i. We were able to reproduce enteric disease using only a pathogenic field isolate (MG10) of TCoV that negatively affected growth performance and intestinal morphology of young turkey poults.
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Affiliation(s)
- M H Gomaa
- Department of Virology, Faculty of Veterinary Medicine, Kafrelsheikh, Egypt
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Jindal N, Patnayak DP, Chander Y, Ziegler AF, Goyal SM. Detection and molecular characterization of enteric viruses from poult enteritis syndrome in turkeys. Poult Sci 2010; 89:217-26. [PMID: 20075272 PMCID: PMC7107190 DOI: 10.3382/ps.2009-00424] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study was conducted to detect and characterize enteric viruses [rotavirus, turkey astrovirus-2 (TAstV-2), reovirus, and turkey coronavirus] from cases of poult enteritis syndrome (PES) in Minnesota turkeys. Of the intestinal contents collected from 43 PES cases, 25 were positive for rotavirus and 13 for small round viruses by electron microscopy (EM). Of the enteric virus-positive cases by EM (n=27), 16 cases had rotavirus or small round viruses alone and the remaining 11 cases had both viruses. None of the cases were positive for reovirus or coronavirus by EM. However, with reverse transcription-PCR (RT-PCR), 40 cases (93%) were positive for rotavirus, 36 (84%) for TAstV-2, and 17 (40%) for reovirus. None of the cases were positive for turkey coronavirus by RT-PCR. The viruses from all cases were detected either alone or in combination of 2 or 3 by RT-PCR. Thus, 8 (19%) cases were positive for a single virus, whereas a combination of viruses was detected in the remaining 35 (81%) cases. The rota-TAstV-2 combination was the most predominant (n=18 cases). Fifteen cases were positive for all 3 viruses. The rotaviruses had sequence homology of 89.8 to 100% with previously published sequences of turkey rotaviruses at the nucleotide level. The TAstV-2 had sequence homology of 84.6 to 98.7% with previously published TAstV-2, whereas reoviruses had sequence homology of 91.6 to 99.3% with previously published sequences of turkey reoviruses. Phylogenetic analysis revealed that rota- and reoviruses clustered in a single group, whereas TAstV-2 clustered in 2 different groups. In conclusion, a larger number of PES cases was positive for rotavirus, TAstV-2, and reovirus by RT-PCR than with EM. The presence of more than one virus and changes at the genetic level in a virus may affect the severity of PES in turkey flocks.
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Affiliation(s)
- N Jindal
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul 55108, USA
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Day JM, Zsak L. Determination and analysis of the full-length chicken parvovirus genome. Virology 2010; 399:59-64. [PMID: 20097398 PMCID: PMC7173076 DOI: 10.1016/j.virol.2009.12.027] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Revised: 11/17/2009] [Accepted: 12/17/2009] [Indexed: 01/07/2023]
Abstract
Viral enteric disease in poultry is an ongoing problem in many parts of the world. Many enteric viruses have been identified in turkeys and chickens, including avian astroviruses, rotaviruses, reoviruses, and coronaviruses. Through the application of a molecular screening method targeting particle-associated nucleic acid (PAN), we recently described the detection and partial characterization of a novel enteric parvovirus in chickens. Subsequent surveys of intestinal homogenates from turkeys and chickens in the United States revealed widespread occurrence of parvovirus in poultry. Here we report the first full genome sequence of a novel chicken parvovirus, ChPV ABU-P1. ChPV ABU-P1 genome organization, predicted amino acid sequence, and phylogenetic relationships with other described parvoviruses are discussed.
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Affiliation(s)
- J Michael Day
- Southeast Poultry Research Laboratory, Agricultural Research Service, United States Department of Agriculture, 934 College Station Road, Athens, GA 30605, USA
| | - Laszlo Zsak
- Southeast Poultry Research Laboratory, Agricultural Research Service, United States Department of Agriculture, 934 College Station Road, Athens, GA 30605, USA.
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35
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Abstract
From 2003 to 2006, samples of intestinal content and spleens from 10-day-old to 6-week-old fattening turkeys showing clinical signs of enteritis were analyzed by specific PCR and RT-PCRs for detection of haemorrhagic enteritis virus (HEV), avian reovirus (ARV), turkey astrovirus-2 (TastV-2), and turkey coronavirus (TCV). A total of 23 flocks from 6 farms were included in the study. Specific sequence for HEV hexon gene was present in 6 samples from turkeys younger than and in one turkey at 6 weeks of age. A product of TastV-2 capsid gene was detected in 17/23 intestinal content samples. A 626-bp band of sigma A (S2) encoding gene segment from avian reovirus was present in three samples, all from the same farm. Sequence analysis of 450 bp fragment of avian reovirus sigma A encoding gene sequence showed that our strain had the identity of 91.3% with the strains 138, 2408, 1733, 919, T6, and Os161. No TCV specific PCR band was found in any sample. Four flocks were positive simultaneously for HEV and TastV-2, and three flocks on TastV-2 and ARV. Severity of poult enteritis described in our study is caused by immunosuppressive TastV-2 in combination with HEV or ARV.
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36
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Jindal N, Patnayak DP, Ziegler AF, Lago A, Goyal SM. Experimental reproduction of poult enteritis syndrome: clinical findings, growth response, and microbiology. Poult Sci 2009; 88:949-58. [PMID: 19359682 PMCID: PMC7107170 DOI: 10.3382/ps.2008-00490] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Poult enteritis syndrome (PES) is an infectious disease of turkey poults characterized by diarrhea, dullness, and depression. Five experiments were conducted to reproduce the disease in turkey poults using intestinal contents of PES-affected birds. In all experiments, poults at 14 d of age were divided into 4 groups and were orally given 2 mL of unfiltered supernatant, filtered supernatant, sediment dissolved in PBS, or PBS alone. Inocula in experiments 1, 3, and 5 consisted of intestinal contents from PES-affected birds of less than 2 wk of age, whereas those in experiments 2 and 4 consisted of intestinal contents from PES-affected birds of 4 to 6 wk of age. Poults in all groups were observed daily for clinical signs. The BW and microbiological criteria in experiments 1, 3, and 5 were evaluated at 5, 10, and 15 d postinoculation, whereas in experiments 2 and 4, these observations were made at 10 and 20 d postinoculation. Rotavirus, astrovirus, and Salmonella were present in all 5 inocula. Diarrhea and depression were the major signs in poults given PES material. Significant retardation of growth was observed in poults given any of the 3 PES materials, but this effect was more pronounced in poults given the sediment inoculum. Rotavirus, astrovirus, and Salmonella were detected in poults given PES material. In some cases, enterovirus was also detected. No major difference was noticed in experimental reproduction of PES when intestinal contents from different age birds were used as the inoculum.
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Affiliation(s)
- N Jindal
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul 55108, USA
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37
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Zsak L, Strother KO, Kisary J. Partial genome sequence analysis of parvoviruses associated with enteric disease in poultry. Avian Pathol 2008; 37:435-41. [PMID: 18622862 DOI: 10.1080/03079450802210648] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Poult enteritis mortality syndrome (PEMS) of turkeys and runting-stunting syndrome (RSS) of chickens are significant viral enteric diseases of poultry. Although a number of different viruses, including avian reoviruses, rotaviruses, astroviruses and coronaviruses, have been isolated from the intestinal contents of birds in affected poultry flocks, their role in PEMS and RSS is not yet understood. Here, we report the application of a molecular screening method to detection of novel viruses in intestinal samples of chickens and turkeys exhibiting characteristic signs of enteric disease. The technique is based on random amplification of particle-associated nucleic acids in clinical samples. Using this method we successfully identified parvovirus DNA sequences in intestinal homogenates of affected birds. This is the first time partial genomic sequences of autonomously replicating chicken and turkey parvoviruses have been described. Sequence analysis of the left end of the genome, including the complete non-structural gene, demonstrated that the chicken and turkey parvoviruses were closely related to each other and were representative of a novel member of the Parvovirus family. These parvoviruses may play a significant role in the aetiology of PEMS and RSS.
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Affiliation(s)
- L Zsak
- Southeast Poultry Research Laboratory, USDA-ARS, Athens, GA 30605, USA.
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38
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Da Silva SEL, Bonetti AM, Petrocelli ATM, Ferrari HF, Luvizotto MCR, Cardoso TC. Detection of Turkey astrovirus in young poults affected with poult enteritis complex in Brazil. J Vet Med Sci 2008; 70:629-31. [PMID: 18628608 DOI: 10.1292/jvms.70.629] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Reverse transcription polymerase chain reaction (RT-PCR) of turkey astrovirus (TAstV) capsid and polymerase genes was applied to the bursa of Fabricius (BF), thymus (TH), spleen (SP) and cloacal swabs (CS) of young poults with "Poult enteritis complex" (PEC). The histological lesions included atrophy, lymphoid depletion, cellular infiltration and necrosis of the BF, TH and SP, respectively. The RT-PCR reactions were positive for the polymerase gene of TAstV-2 in all 100 CSs, 7 out of 10 of BFs and 10 out of 20 THs and SPs, respectively. Five out of 10 THs and SPs samples, considered to be negative by RT-PCR, were positive when specific primers designed for the TAstV-2 capsid gene were applied. This is the first description of turkey astrovirus infection presenting PEC in Latin America.
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Affiliation(s)
- Sérgio E L Da Silva
- Universidade Federal de Uberlândia, (UFUB) Programa de Pós-graduação Genética e Bioquímica, MG, Brazil
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Pantin-Jackwood MJ, Day JM, Jackwood MW, Spackman E. Enteric viruses detected by molecular methods in commercial chicken and turkey flocks in the United States between 2005 and 2006. Avian Dis 2008; 52:235-44. [PMID: 18646452 DOI: 10.1637/8174-111507-reg.1] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Intestinal samples collected from 43 commercial broiler and 33 commercial turkey flocks from all regions of the United States during 2005 and 2006 were examined for the presence of astrovirus, rotavirus, reovirus, and coronavirus by reverse transcription-polymerase chain reaction (PCR), and for the presence of groups 1 and 2 adenovirus by PCR. Phylogenetic analysis was performed to further characterize the viruses and to evaluate species association and geographic patterns. Astroviruses were identified in samples from 86% of the chicken flocks and from 100% of the turkey flocks. Both chicken astrovirus and avian nephritis virus (ANV) were identified in chicken samples, and often both viruses were detected in the same flock. Turkey astrovirus type-2 and turkey astrovirus type-1 were found in 100% and 15.4% of the turkey flocks, respectively. In addition, 12.5% of turkey flocks were positive for ANV. Rotaviruses were present in 46.5% of the chicken flocks tested and in 69.7% of the turkey flocks tested. Based upon the rotavirus NSP4 gene sequence, the chicken and turkey origin rotaviruses assorted in a species-specific manner. The turkey origin rotaviruses also assorted based upon geographical location. Reoviruses were identified in 62.8% and 45.5% of chicken and turkey flocks, respectively. Based on the reovirus S4 gene segment, the chicken and turkey origin viruses assorted separately, and they were distinct from all previously reported avian reoviruses. Coronaviruses were detected in the intestinal contents of chickens, but not turkeys. Adenoviruses were not detected in any chicken or turkeys flocks. Of the 76 total chicken and turkey flocks tested, only three chicken flocks were negative for all viruses targeted by this study. Most flocks were positive for two or more of the viruses, and overall no clear pattern of virus geographic distribution was evident. This study provides updated enteric virus prevalence data for the United States using molecular methods, and it reinforces that enteric viruses are widespread in poultry throughout the United States, although the clinical importance of most of these viruses remains unclear.
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Affiliation(s)
- Mary J Pantin-Jackwood
- Southeast Poultry Research Laboratory, USDA, Agricultural Research Service, Athens, GA 30605, USA
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Pantin-Jackwood MJ, Spackman E, Day JM, Rives D. Periodic monitoring of commercial turkeys for enteric viruses indicates continuous presence of astrovirus and rotavirus on the farms. Avian Dis 2007; 51:674-80. [PMID: 17992925 DOI: 10.1637/0005-2086(2007)51[674:pmoctf]2.0.co;2] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A longitudinal survey to detect enteric viruses in intestinal contents collected from turkeys in eight commercial operations and one research facility was performed using molecular detection methods. Intestinal contents were collected from turkeys prior to placement, with each flock resampled at 2, 4, 6, 8, 10, and 12 wk of age. The samples were screened for astrovirus, rotavirus, reovirus, and turkey coronavirus (TCoV) by a reverse transcriptase and polymerase chain reaction (RT-PCR), and for groups 1 and 2 adenovirus by PCR. Rotavirus was the only virus detected prior to placement (7 of 16 samples examined). All of the commercial flocks were positive for rotavirus and astrovirus from 2 until 6 wk of age, and most were intermittently positive until 12 wk of age, when the birds were processed. Of the 96 samples collected from birds on the farms, 89.5% were positive for astrovirus, and 67.7% were positive for rotavirus. All flocks were negative for TCoV, reovirus, and group 1 adenovirus at all time points, and positive for group 2 adenovirus (hemorrhagic enteritis virus) at 6 wk of age. All the flocks monitored were considered healthy or normal by field personnel. Turkeys placed on research facilities that had been empty for months and thoroughly cleaned had higher body weights and lower feed conversion rates at 5 wk of age when compared to turkeys placed on commercial farms. Intestinal samples collected at 1, 2, and 3 wk of age from these turkeys were free of enteric viruses. This report demonstrates that astroviruses and rotaviruses may be present within a turkey flock through the life of the flock. Comparison of infected birds with one group of turkeys that were negative for enteric viruses by the methods used here suggests that astrovirus and/or rotavirus may affect production. The full impact on flock performance needs to be further determined.
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Affiliation(s)
- Mary J Pantin-Jackwood
- Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA.
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Michael Day J, Spackman E, Pantin-Jackwood M. A Multiplex RT-PCR Test for the Differential Identification of Turkey Astrovirus Type 1, Turkey Astrovirus Type 2, Chicken Astrovirus, Avian Nephritis Virus, and Avian Rotavirus. Avian Dis 2007; 51:681-4. [DOI: 10.1637/0005-2086(2007)51[681:amrtft]2.0.co;2] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Pantin-Jackwood MJ, Spackman E, Day JM. Pathology and virus tissue distribution of Turkey origin reoviruses in experimentally infected Turkey poults. Vet Pathol 2007; 44:185-95. [PMID: 17317795 DOI: 10.1354/vp.44-2-185] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The pathogenesis of 4 isolates of turkey-origin reovirus (NC/SEP-R44/03, NC/98, TX/98, and NC/85) and 1 chicken-origin reovirus (1733) was examined by infecting specific pathogen free (SPF) poults. These turkey-origin reovirus (TRV) isolates were collected from turkey flocks experiencing poult enteritis and are genetically distinct from previously reported avian reoviruses. Microscopic examination of the tissues collected from the TRV-infected poults revealed different degrees of bursal atrophy characterized by lymphoid depletion and increased fibroplasia between the bursal follicles. To understand the relationship between virus spread and replication, and the induction of lesions, immunohistochemical staining (IHC) for viral antigen, in situ hybridization (ISH) for the detection of viral RNA, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay for the detection of apoptosis in affected tissues was performed. Both IHC and ISH revealed viral antigen and RNA in the surface epithelial cells of the bursa, in macrophages in the interstitium of the bursa and, to lesser degree, in splenic red pulp macrophages and intestinal epithelial cells. Increased apoptosis of bursal lymphocytes and macrophages was observed at 2 and 5 days postinoculation. No lesions were found in tissues from poults inoculated with the virulent chicken-origin strain, however viral antigen was detected in the bursa and the intestine. Although all TRVs studied displayed similar tissue tropism, there were substantial differences in the severity of the lesions produced. Poults inoculated with NC/SEP-R44/03 or NC/98 had moderate to severe bursal atrophy, whereas poults inoculated with TX/98 or NC/85 presented a mild to moderate bursal lymphoid depletion. The lymphoid depletion observed in the bursa appears to be the effect of an indirectly induced apoptosis and would most likely result in immune dysfunction in poults infected with TRV.
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Affiliation(s)
- M J Pantin-Jackwood
- Southeast Poultry Research Laboratory, US Department of Agriculture, Agricultural Research Service, 934 College Station Road, Athens, GA 30605, USA.
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Pantin-Jackwood MJ, Spackman E, Woolcock PR. Molecular characterization and typing of chicken and turkey astroviruses circulating in the United States: implications for diagnostics. Avian Dis 2006; 50:397-404. [PMID: 17039840 DOI: 10.1637/7512-020606r.1] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Avian astroviruses were detected by reverse transcriptase and polymerase chain reaction in intestinal contents collected from commercial chickens and turkeys from throughout the United States from 2003 through 2005. Astroviruses were detected in birds from both healthy and poorly performing flocks with or without enteric disease. Phylogenetic analysis was performed with sequence data from the polymerase (ORF-1b) genes of 41 turkey-origin astroviruses and 23 chicken-origin astroviruses. All currently available avian astrovirus sequence data and selected mammalian astrovirus sequence data were included in the analysis. Four groups of avian astroviruses were observed by phylogenetic analysis: turkey astrovirus type 1 (TAstV-1)-like viruses, turkey astrovirus type 2 (TAstV-2)-like viruses, both detected in turkeys; avian nephritis virus (ANV)-like viruses, detected in both chickens and turkeys; and a novel group of chicken-origin astroviruses (CAstV). Among these four groups, amino acid identity was between 50.1% and 73.8%, and was a maximum of 49.4% for all avian isolates when compared with the mammalian astroviruses. There were multiple phylogenetic subgroups within the TAstV-2, ANV, and CAstV groups based on 9% nucleotide sequence divergence. Phylogenetic analysis revealed no clear assortment by geographic region or isolation date. Furthermore, no correlation was observed between the detection of a particular astrovirus and the presence of enteric disease or poor performance. Based on these data, a revision of the present taxonomic classification for avian astroviruses within the genus Avastrovirus is warranted.
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Affiliation(s)
- Mary J Pantin-Jackwood
- Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, 934 College Station Rd., Athens, Georgia 30605, USA
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Pantin-Jackwood MJ, Spackman E, Woolcock PR. Phylogenetic analysis of Turkey astroviruses reveals evidence of recombination. Virus Genes 2006; 32:187-92. [PMID: 16604451 PMCID: PMC7089065 DOI: 10.1007/s11262-005-6875-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2005] [Accepted: 08/13/2005] [Indexed: 12/04/2022]
Abstract
Sequence data was obtained from the capsid (ORF-2) and the polymerase (ORF-lb) genes of 23 turkey astrovirus (TAstV) isolates collected from commercial turkey flocks around the United States between 2003 and 2004. A high level of genetic variation was observed among the isolates, particularly in the capsid gene, where nucleotide sequence identity among them was as low as 69%. Isolates collected on the same farm, on the same day, but from different houses could have as little as 72% identity between their capsid gene sequences when compared. Phylogenetic analysis of the capsid gene revealed no clear assortment by geographic region or isolation date. The polymerase gene was more conserved with between 86 and 99% nucleotide identity and did assort in a geographic manner. Based on differing topologies of the capsid and polymerase gene phylogenetic trees, TAstV appears to undergo recombination.
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Affiliation(s)
- Mary J. Pantin-Jackwood
- Southeast Poultry Research Laboratory, Agriculture Research Service, US Department of Agriculture, 934 College Station Rd., Athens, GA 30605 USA
| | - Erica Spackman
- Southeast Poultry Research Laboratory, Agriculture Research Service, US Department of Agriculture, 934 College Station Rd., Athens, GA 30605 USA
| | - Peter R. Woolcock
- California Animal Health and Food Safety Laboratory System, University of California Davis, Davis, California 39616 USA
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Spackman E, Kapczynski D, Sellers H. Multiplex real-time reverse transcription-polymerase chain reaction for the detection of three viruses associated with poult enteritis complex: turkey astrovirus, turkey coronavirus, and turkey reovirus. Avian Dis 2005; 49:86-91. [PMID: 15839418 DOI: 10.1637/7265-082304r] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Poult enteritis complex (PEC) is an economically important disease of young turkeys characterized by diarrhea, poor weight gain, and, in some cases, high mortality. Although PEC is considered to be a polymicrobial disease, numerous viruses, including turkey coronavirus (TCV), turkey astrovirus type 2 (TAstV-2), and avian reoviruses (ARVs), have been associated with PEC-like disease. Real-time reverse transcription-polymerase chain reaction (RRT-PCR), a highly sensitive and specific detection method for viral RNA, was developed in a multiplex format for the simultaneous detection of TAstV-2 and TCV and for the detection of two genetic types of ARV. Assay sensitivity was determined using in vitro transcribed RNA and varied by target between 150 gene copies for TAstV-2 alone and 2200 gene copies for TCV when multiplexed. Virus detection was evaluated with samples collected from poults inoculated at 1 day of age with each of the viruses. Cloacal swabs and intestinal samples were obtained at 1, 2, 3, 4, 6, 9, 14, 17, and 21 days after inoculation, processed, and tested for virus detection by RRT-PCR Cloacal swabs from TAstV-2- and TCV-infected poults were shown to have sensitivity for virus detection similar to that of intestinal samples when compared directly. ARV detection by RRT-PCR was compared with virus isolation and had similar sensitivity.
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Affiliation(s)
- Erica Spackman
- Southeast Poultry Research Laboratory, USDA-ARS, 934 College Station Road, Athens, GA 30605, USA
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Sellers HS, Koci MD, Linnemann E, Kelley LA, Schultz-Cherry S. Development of a Multiplex Reverse Transcription–Polymerase Chain Reaction Diagnostic Test Specific for Turkey Astrovirus and Coronavirus. Avian Dis 2004; 48:531-9. [PMID: 15529975 DOI: 10.1637/7128] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A multiplex reverse transcription-polymerase chain reaction (RT-PCR) assay was developed for the simultaneous detection of two enteric viruses of poultry: turkey enteric coronavirus (TCV) and turkey astrovirus (TAstV). PCR primers were designed to conserved regions within the nucleocapsid gene of TCV and to the polymerase gene of TAstV-2. The primer pairs were successfully used in a multiplex RT-PCR to detect nucleic acid of TAstV-2 and TCV. The test was optimized for use with intestines/feces from naturally infected turkeys. The primers were specific and did not amplify other common RNA or DNA avian viruses. The detection limit was determined to be 10 ng of RNA used as starting template. The use of this specific test allows the rapid and early diagnosis of two financially costly viruses affecting the commercial turkey industry.
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Affiliation(s)
- Holly S Sellers
- Department of Avian Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
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