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Zappulli V, Ferro S, Bonsembiante F, Brocca G, Calore A, Cavicchioli L, Centelleghe C, Corazzola G, De Vreese S, Gelain ME, Mazzariol S, Moccia V, Rensi N, Sammarco A, Torrigiani F, Verin R, Castagnaro M. Pathology of Coronavirus Infections: A Review of Lesions in Animals in the One-Health Perspective. Animals (Basel) 2020; 10:E2377. [PMID: 33322366 PMCID: PMC7764021 DOI: 10.3390/ani10122377] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/04/2020] [Accepted: 12/09/2020] [Indexed: 12/13/2022] Open
Abstract
Coronaviruses (CoVs) are worldwide distributed RNA-viruses affecting several species, including humans, and causing a broad spectrum of diseases. Historically, they have not been considered a severe threat to public health until two outbreaks of COVs-related atypical human pneumonia derived from animal hosts appeared in 2002 and in 2012. The concern related to CoVs infection dramatically rose after the COVID-19 global outbreak, for which a spill-over from wild animals is also most likely. In light of this CoV zoonotic risk, and their ability to adapt to new species and dramatically spread, it appears pivotal to understand the pathophysiology and mechanisms of tissue injury of known CoVs within the "One-Health" concept. This review specifically describes all CoVs diseases in animals, schematically representing the tissue damage and summarizing the major lesions in an attempt to compare and put them in relation, also with human infections. Some information on pathogenesis and genetic diversity is also included. Investigating the lesions and distribution of CoVs can be crucial to understand and monitor the evolution of these viruses as well as of other pathogens and to further deepen the pathogenesis and transmission of this disease to help public health preventive measures and therapies.
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Affiliation(s)
- Valentina Zappulli
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Silvia Ferro
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Federico Bonsembiante
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
- Department of Animal Medicine, Productions and Health, University of Padua, Legnaro, 35020 Padua, Italy
| | - Ginevra Brocca
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Alessandro Calore
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Laura Cavicchioli
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Cinzia Centelleghe
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Giorgia Corazzola
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Steffen De Vreese
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
- Laboratory of Applied Bioacoustics, Technical University of Catalunya, BarcelonaTech, Vilanova i la Geltrù, 08800 Barcelona, Spain
| | - Maria Elena Gelain
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Sandro Mazzariol
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Valentina Moccia
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Nicolò Rensi
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Alessandro Sammarco
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
- Department of Neurology and Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
| | - Filippo Torrigiani
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Ranieri Verin
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
| | - Massimo Castagnaro
- Department of Comparative Biomedicine and Food Science, University of Padua, Legnaro, 35020 Padua, Italy; (V.Z.); (F.B.); (G.B.); (A.C.); (L.C.); (C.C.); (G.C.); (S.D.V.); (M.E.G.); (S.M.); (V.M.); (N.R.); (A.S.); (F.T.); (R.V.); (M.C.)
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Hauck R, Gallardo RA, Woolcock PR, Shivaprasad HL. A Coronavirus Associated with Runting Stunting Syndrome in Broiler Chickens. Avian Dis 2017; 60:528-34. [PMID: 27309300 DOI: 10.1637/11353-122215-case] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Runting stunting syndrome (RSS) is a disease condition that affects broilers and causes impaired growth and poor feed conversion because of enteritis characterized by pale and distended small intestines with watery contents. The etiology of the disease is multifactorial, and a large variety of viral agents have been implicated. Here we describe the detection and isolation of an infectious bronchitis virus (IBV) -like coronavirus from the intestines of a flock of 60,000 14-day-old brown/red broiler chicks. The birds showed typical clinical signs of RSS including stunting and uneven growth. At necropsy, the small intestines were pale and distended with watery contents. Histopathology of the intestines revealed increased cellularity of the lamina propria, blunting of villi, and cystic changes in the crypts. Negative stain electron microscopy of the intestinal contents revealed coronavirus particles. Transmission electron microscopy of the intestine confirmed coronavirus in the cytoplasm of enterocytes. Using immunohistochemistry (IHC), IBV antigen was detected in the intestinal epithelial cells as well as in the proventriculus and pancreas. There were no lesions in the respiratory system, and no IBV antigen was detected in trachea, lung, air sac, conjunctiva, and cecal tonsils. A coronavirus was isolated from the intestine of chicken embryos but not from the allantoic sac inoculated with the intestinal contents of the broiler chicks. Sequencing of the S1 gene showed nucleic acid sequence identities of 93.8% to the corresponding region of IBV California 99 and of 85.7% to IBV Arkansas. Nucleic acid sequence identities to other IBV genotypes were lower. The histopathologic lesions in the intestines were reproduced after experimental infection of specific-pathogen-free chickens inoculated in the conjunctiva and nares. Five days after infection, six of nine investigated birds showed enteritis associated with IBV antigen as detected by IHC. In contrast to the field infection, birds in the experimental group showed clear respiratory signs and lesions in the upper respiratory tract. The results suggest a broader tissue tropism of this isolate, which might be related to the mutations in the S1 gene.
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Affiliation(s)
- Rüdiger Hauck
- A Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA
| | - Rodrigo A Gallardo
- A Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA
| | - Peter R Woolcock
- B University of California, California Animal Health and Food Safety Laboratory System, 620 West Health Science Dr., Davis, CA 95616
| | - H L Shivaprasad
- C University of California, California Animal Health and Food Safety Laboratory System, 18830 Rd. 112, Tulare, CA 93274
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Loa CC, Wu CC, Lin TL. A Multiplex Polymerase Chain Reaction for Differential Detection of Turkey Coronavirus from Chicken Infectious Bronchitis Virus and Bovine Coronavirus. SPRINGER PROTOCOLS HANDBOOKS 2016. [PMCID: PMC7122580 DOI: 10.1007/978-1-4939-3414-0_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
A multiplex polymerase chain reaction (PCR) method for differential detection of turkey coronavirus (TCoV), infectious bronchitis virus (IBV), and bovine coronavirus (BCoV) is presented in this chapter. Primers are designed from the conserved or variable regions of nucleocapsid (N) or spike (S) protein genes of TCoV, IBV, and BCoV and used in the same PCR reaction. Reverse transcription followed by PCR reaction is used to amplify a portion of N or S gene of the corresponding coronaviruses. Two PCR products, a 356-bp band corresponding to N gene and a 727-bp band corresponding to S gene, are obtained for TCoV. In contrast, one PCR product of 356 bp corresponding to a fragment of N gene is obtained for IBV strains and one PCR product of 568 bp corresponding to a fragment of S gene is obtained for BCoV.
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PCR Amplification and Sequencing Analysis of Full-Length Turkey Coronavirus Spike Gene. SPRINGER PROTOCOLS HANDBOOKS 2016. [PMCID: PMC7122697 DOI: 10.1007/978-1-4939-3414-0_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Turkey coronaviral enteritis caused by turkey coronavirus (TCoV) continues to infect turkey flocks, resulting in significant economic loss. Determining and understanding genetic relationships among different TCoV isolates or strains is important for controlling the disease. Using two-step RT-PCR assays that amplify the full length of TCoV spike (S) gene, TCoV isolates can be sequenced, analyzed, and genotyped. Described in this chapter is the protocol on PCR amplification and sequencing analysis of full-length TCoV S gene. Such protocol is useful in molecular epidemiology for establishing an effective strategy to control the transmission of TCoV among turkey flocks.
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Genotyping of turkey coronavirus field isolates from various geographic locations in the Unites States based on the spike gene. Arch Virol 2015; 160:2719-26. [PMID: 26254026 PMCID: PMC7086652 DOI: 10.1007/s00705-015-2556-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 07/27/2015] [Indexed: 11/22/2022]
Abstract
Turkey flocks have experienced turkey coronaviral enteritis sporadically in the United States since the 1990s. Twenty-four field isolates of turkey coronavirus (TCoV) from multiple states in the United States were recovered from 1994 to 2010 to determine the genetic relationships among them. The entire spike (S) gene of each TCoV isolate was amplified and sequenced. Pairwise comparisons were performed using the Clustal W program, revealing 90.0 % to 98.4 % sequence identity in the full-length S protein, 77.6 % to 96.6 % in the amino terminus of the S1 subunit (containing one hypervariable region in S1a), and 92.1 % to 99.3 % in the S2 subunit at the deduced amino acid sequence level. The conserved motifs, including two cleavage recognition sequences of the S protein, two heptad repeats, the transmembrane domain, and the Golgi retention signal were identified in all TCoV isolates. Phylogenetic analysis based on the full-length S gene was used to distinguish North American TCoV isolates from French TCoV isolates. Among the North American TCoV isolates, three distinct genetic groups with 100 % bootstrap support were observed. North Carolina isolates formed group I, Texas isolates formed group II, and Minnesota isolates formed Group III. The S genes of 24 TCoV isolates from the United States remained conserved because they contained predominantly synonymous substitutions. The findings of the present study suggest endemic circulation of distinct TCoV genotypes in different geographic locations.
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Day JM, Gonder E, Jennings S, Rives D, Robbins K, Tilley B, Wooming B. Investigating turkey enteric coronavirus circulating in the Southeastern United States and Arkansas during 2012 and 2013. Avian Dis 2014; 58:313-7. [PMID: 25055640 DOI: 10.1637/10674-092313-resnote.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Periodic monitoring of poultry flocks in the United States via molecular diagnostic methods has revealed a number of potential enteric viral pathogens in continuous circulation in turkeys and chickens. Recently turkey integrators in the Southeastern United States and Arkansas experienced an outbreak of moderate to severe enteritis associated with turkey enteric coronavirus (TCoV), and numerous enteric samples collected from turkey flocks in these areas tested positive for TCoV via real-time reverse-transcriptase PCR (RRT-PCR). This report details the subsequent sequence and phylogenetic analysis of the TCoV spike glycoprotein and the comparison of outbreak-associated isolates to sequences in the public database. TCoVs investigated during the present outbreak grouped geographically based upon state of origin, and the RRT-PCR assay was a good indicator of subsequent seroconversion by TCoV-positive turkey flocks.
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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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Maurel S, Toquin D, Briand FX, Queguiner M, Allee C, Bertin J, Ravillion L, Retaux C, Turblin V, Morvan H, Eterradossi N. First full-length sequences of the S gene of European isolates reveal further diversity among turkey coronaviruses. Avian Pathol 2011; 40:179-89. [PMID: 21500038 DOI: 10.1080/03079457.2011.551936] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
An increasing incidence of enteric disorders clinically suggestive of the poult enteritis complex has been observed in turkeys in France since 2003. Using a newly designed real-time reverse transcriptase-polymerase chain reaction assay specific for the nucleocapsid (N) gene of infectious bronchitis virus (IBV) and turkey coronaviruses (TCoV), coronaviruses were identified in 37% of the intestinal samples collected from diseased turkey flocks. The full-length spike (S) gene of these viruses was amplified, cloned and sequenced from three samples. The French S sequences shared 98% identity at both the nucleotide and amino acid levels, whereas they were at most 65% and 60% identical with North American (NA) TCoV and at most 50% and 37% identical with IBV at the nucleotide and amino acid levels, respectively. Higher divergence with NA TCoV was observed in the S1-encoding domain. Phylogenetic analysis based on the S gene revealed that the newly detected viruses form a sublineage genetically related with, but significantly different from, NA TCoV. Additionally, the RNA-dependent RNA polymerase gene and the N gene, located on the 5' and 3' sides of the S gene in the coronavirus genome, were partially sequenced. Phylogenetic analysis revealed that both the NA TCoV and French TCoV (Fr TCoV) lineages included some IBV relatives, which were however different in the two lineages. This suggested that different recombination events could have played a role in the evolution of the NA and Fr TCoV. The present results provide the first S sequence for a European TCoV. They reveal extensive genetic variation in TCoV and suggest different evolutionary pathways in North America and Europe.
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Affiliation(s)
- S Maurel
- Anses-French Agency for Food, Environmental and Occupational Health Safety, Ploufragan-Plouzané Laboratory, Avian and Rabbit Virology, Immunology, and Parasitology Unit, Ploufragan, France
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Chen YN, Wu CC, Lin TL. Identification and characterization of a neutralizing-epitope-containing spike protein fragment in turkey coronavirus. Arch Virol 2011; 156:1525-35. [PMID: 21594597 PMCID: PMC7086772 DOI: 10.1007/s00705-011-1020-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 05/02/2011] [Indexed: 12/27/2022]
Abstract
Little is known about the neutralizing epitopes in turkey coronavirus (TCoV). The spike (S) protein gene of TCoV was divided into 10 fragments to identify the antigenic region containing neutralizing epitopes. The expression and antigenicity of S fragments was confirmed by immunofluorescence antibody (IFA) assay using an anti-histidine monoclonal antibody or anti-TCoV serum. Polyclonal antibodies raised against expressed S1 (amino acid position 1 to 573 from start codon of S protein), 4F/4R (482-678), 6F/6R (830-1071), or Mod4F/Epi4R (476-520) S fragment recognized native S1 protein and TCoV in the intestines of TCoV-infected turkey embryos. Anti-TCoV serum reacted with recombinant 4F/4R, 6F/6R, and Mod4F/Epi4R in a western blot. The results of a virus neutralization assay indicated that the carboxyl terminal region of the S1 protein (Mod4F/Epi4R) or the combined carboxyl terminal S1 and amino terminal S2 protein (4F/4R) possesses the neutralizing epitopes, while the S2 fragment (6F/6R) contains antigenic epitopes but not neutralizing epitopes.
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Affiliation(s)
- Yi-Ning Chen
- Department of Comparative Pathobiology, Purdue University, 406 South University Street, West Lafayette, IN 47907, USA
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Specific real-time reverse transcription-polymerase chain reaction for detection and quantitation of turkey coronavirus RNA in tissues and feces from turkeys infected with turkey coronavirus. J Virol Methods 2009; 163:452-8. [PMID: 19917315 PMCID: PMC7112835 DOI: 10.1016/j.jviromet.2009.11.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 10/28/2009] [Accepted: 11/05/2009] [Indexed: 11/21/2022]
Abstract
Turkey coronavirus (TCoV) infection causes acute atrophic enteritis in the turkey poults, leading to significant economic loss in the U.S. turkey industry. Rapid detection, differentiation, and quantitation of TCoV are critical to the diagnosis and control of the disease. A specific one-step real-time reverse transcription-polymerase chain reaction (RRT-PCR) assay for detection and quantitation of TCoV in the turkey tissues was developed using a dual-labeled fluorescent probe. The fluorogenic probe labeled with a reporter dye (FAM, 6-carboxytetramethylrhodamin) and a quencher dye (AbsoluteQuencher) was designed to bind to a 186 base-pair fragment flanked by the two PCR primers targeting the 3' end of spike gene of TCoV. The assay was performed on different avian viruses and bacteria to determine the specificity as well as serial dilutions of TCoV for the sensitivity. Three animal trials were conducted to further validate the assay. Ten-day-old turkey poults were inoculated orally with 100 EID(50) of TCoV. Intestinal tissues (duodenum, jejunum, ileum, cecum), feces from the cloacal swabs, or feces from the floor were collected at 12 h, 1, 2, 3, 5, 7, and/or 14 days post-inoculation (DPI). RNA was extracted from each sample and subjected to the RRT-PCR. The designed primers and probe were specific for TCoV. Other non-TCoV avian viruses and bacteria were not amplified by RRT-PCR. The assay was highly sensitive and could quantitate between 10(2) and 10(10) copies/microl of viral genome. The viral RNA in the intestine segments reached the highest level, 6x10(15) copies/microl, in the jejunum at 5 DPI. Eighty-four intestine segments assayed by the developed RRT-PCR and immunofluorescence antibody assay (IFA) revealed that there were 6 segments negative for TCoV by both assays, 45 positive for TCoV by IFA, and 77 positive for TCoV by RRT-PCR. Turkey coronavirus was detected in the feces from the cloacal swabs or floor 1-14 DPI; however, the viral RNA load varied among different turkey poults at different intervals from different trials. The highest amount of viral RNA, 2.8x10(10) copies/microl, in the feces was the one from the cloacal swab collected at 1 DPI. The average amount of TCoV RNA in the cloacal fecal samples was 10 times higher than that in the fecal droppings on the floor. Taken together, the results indicated that the developed RRT-PCR assay is rapid, sensitive, and specific for detection, differentiation, and quantitation of TCoV in the turkey tissues and should be helpful in monitoring the progression of TCoV induced acute enteritis in the turkey flocks.
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Cao J, Wu CC, Lin TL. Complete nucleotide sequence of polyprotein gene 1 and genome organization of turkey coronavirus. Virus Res 2008; 136:43-9. [PMID: 18514348 PMCID: PMC7114415 DOI: 10.1016/j.virusres.2008.04.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Revised: 04/12/2008] [Accepted: 04/18/2008] [Indexed: 11/30/2022]
Abstract
The complete nucleotide sequence of polyprotein gene 1 and the assembled full-length genome sequence are presented for turkey coronavirus (TCoV) isolates 540 and ATCC. The TCoV polyprotein gene encoded two open reading frames (ORFs), which are translated into two products, pp1a and pp1ab, the latter being produced via −1 frameshift translation. TCoV polyprotein pp1a and pp1ab were predicted to be processed to 15 non-structure proteins (nsp2–nsp16), with nsp1 missing. ClustalW analysis revealed 88.99% identity and 96.99% similarity for pp1ab between TCoV and avian infectious bronchitis virus (IBV) at the amino acid level. The whole genome consists of 27,749 nucleotides for 540 and 27,816 nucleotides for ATCC, excluding the poly(A) tail. A total of 13 ORFs were predicted for TCoV. Five subgenomic RNAs were detected from ATCC-infected turkey small intestines by Northern blotting. The whole genome sequence had 86.9% identity between TCoV and IBV, supporting that TCoV is a group 3 coronavirus.
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Affiliation(s)
- Jianzhong Cao
- Department of Comparative Pathobiology, 406 South University Street, Purdue University, West Lafayette, IN 47907, USA.
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