J Michael Day

Agricultural Research Service, ERV, Texas, United States

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Publications (24)39.69 Total impact

  • Laszlo Zsak · Ra Mi Cha · Fenglan Li · J. Michael Day
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    ABSTRACT: RESUMEN Nota de Investigación- Especificidad de hospedador y relaciones filogenéticas de parvovirus de pollos y pavos. La inoculación de pollos y pavos libres de patógenos específicos con cinco parvovirus de pollo (ChPV) y cinco parvovirus de pavo (TuPV) dio lugar a la replicación viral productiva únicamente en la especie hospedadora homóloga. El árbol filogenético basado en las secuencias de nucleótidos del segmento del gene VP1 reveló una agrupación de las cepas virales específica de hospedador. Estos resultados sugieren que el gene VP1 juega un papel esencial en la especificidad del hospedador de las cepas de parvovirus de pollo y de pavo y podría ser una secuencia blanco relevante para la clasificación de las cepas.
    Avian Diseases 03/2015; 59(1):157-161. DOI:10.1637/10939-092414-ResNote · 1.11 Impact Factor
  • J. Michael Day · Laszlo Zsak
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    ABSTRACT: RESUMEN Investigaciones sobre picornavirus entéricos de los pavos y su asociación con enfermedad entérica en pavipollos. Las investigaciones anteriores acerca de la comunidad viral en el tracto gastrointestinal de las aves comerciales han revelado una serie de virus entéricos nuevos y parcialmente descritos. Es evidente que la comunidad viral en el intestino de las aves comerciales permanece mínimamente caracterizada y no se comprende completamente. Las investigaciones sobre el microbioma del intestino de las aves comerciales han proporcionado alguna información sobre la distribución geográfica y la taxonomía que está evolucionando rápidamente de los picornavirus entéricos aviares. Se llevó a cabo la presente investigación para producir un análisis comparativo de la metagenómica del viroma intestinal de una parvada sana contra una parvada colocada en el campo. Esta investigación reveló una serie de secuencias de picornavirus entéricos que estaban presentes en las aves comerciales en el campo y que estaban completamente ausentes en la parvada sana. Un nuevo ensayo de diagnóstico molecular se utiliza para seguir la diseminación de cepas de campo de picornavirus entéricos en pavipollos comerciales inoculados con homogeneizados intestinales positivos a la presencia de picornavirus preparados a partir de pavos que estaban experimentando enfermedades entéricas moderadas. La propagación de estos nuevos picornavirus entéricos en pavipollos comerciales resultó en una reducción significativa en la ganancia de peso y sugiere que este habitante común del intestino del pavo puede dar lugar a problemas de rendimiento o enfermedad entérica en el campo.
    Avian Diseases 03/2015; 59(1):138-142. DOI:10.1637/10940-092414-RegR · 1.11 Impact Factor
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    J Michael Day · Brian B Oakley · Bruce S Seal · Laszlo Zsak
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    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.
    PLoS ONE 01/2015; 10(1):e0117210. DOI:10.1371/journal.pone.0117210 · 3.23 Impact Factor
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    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.
    Avian Diseases 06/2014; 58(2):313-7. DOI:10.1637/10674-092313-ResNote.1 · 1.11 Impact Factor
  • J Michael Day · Laszlo Zsak
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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.
    Avian Diseases 03/2014; 58(1):137-42. DOI:10.1637/10593-061313-ResNote.1 · 1.11 Impact Factor
  • J Michael Day · Laszlo Zsak
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    ABSTRACT: Despite the importance of the poultry gut, remarkably little is known about the complex gut microbial community. Enteric disease syndromes such as runting-stunting syndrome in broiler chickens and poult enteritis complex in young turkeys are difficult to characterize and reproduce in the laboratory. A great deal of work has been done to characterize the bacterial population in the poultry gut, leading to useful performance-based interventions such as direct-fed microbial preparations. Advances in the application of rapid molecular diagnostics and the advent of the next generation of nucleic acid sequencing have allowed researchers to begin to decipher the microbial community in complex environmental samples. Researchers have made great strides recently in placing names to some of the unknown and undescribed small viruses in the poultry gut such as parvoviruses, picornaviruses, picobirnavirus, and calicivirus. Investigation into the novel avian astroviruses continues, and recent progress has been made in the molecular characterization of the avian rotaviruses. This review will focus on the recent advances that have been made in the discovery, description, and characterization of the multitude of viruses that reside in the poultry gut.
    Avian Diseases 09/2013; 57(3):573-80. DOI:10.1637/10390-092712-Review.1 · 1.11 Impact Factor
  • Laszlo Zsak · Ra Mi Cha · J Michael Day
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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.
    Avian Diseases 03/2013; 57(1):123-7. DOI:10.1637/10371-091212-ResNote.1 · 1.11 Impact Factor
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    Laszlo Zsak · J Michael Day · Brian B Oakley · Bruce S Seal
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    ABSTRACT: The genomic DNA sequence of a novel enteric uncultured microphage, ΦCA82 from a turkey gastrointestinal system was determined utilizing metagenomics techniques. The entire circular, single-stranded nucleotide sequence of the genome was 5,514 nucleotides. The ΦCA82 genome is quite different from other microviruses as indicated by comparisons of nucleotide similarity, predicted protein similarity, and functional classifications. Only three genes showed significant similarity to microviral proteins as determined by local alignments using BLAST analysis. ORF1 encoded a predicted phage F capsid protein that was phylogenetically most similar to the Microviridae ΦMH2K member's major coat protein. The ΦCA82 genome also encoded a predicted minor capsid protein (ORF2) and putative replication initiation protein (ORF3) most similar to the microviral bacteriophage SpV4. The distant evolutionary relationship of ΦCA82 suggests that the divergence of this novel turkey microvirus from other microviruses may reflect unique evolutionary pressures encountered within the turkey gastrointestinal system.
    Virology Journal 06/2011; 8:331. DOI:10.1186/1743-422X-8-331 · 2.09 Impact Factor
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    ABSTRACT: Viral enteric disease is an ongoing economic burden to poultry producers worldwide, and despite considerable research, no single virus has emerged as a likely causative agent and target for prevention and control efforts. Historically, electron microscopy has been used to identify suspect viruses, with many small, round viruses eluding classification based solely on morphology. National and regional surveys using molecular diagnostics have revealed that suspect viruses continuously circulate in United States poultry, with many viruses appearing concomitantly and in healthy birds. High-throughput nucleic acid pyrosequencing is a powerful diagnostic technology capable of determining the full genomic repertoire present in a complex environmental sample. We utilized the Roche/454 Life Sciences GS-FLX platform to compile an RNA virus metagenome from turkey flocks experiencing enteric disease. This approach yielded numerous sequences homologous to viruses in the BLAST nr protein database, many of which have not been described in turkeys. Our analysis of this turkey gut RNA metagenome focuses in particular on the turkey-origin members of the Picornavirales, the Caliciviridae, and the turkey Picobirnaviruses.
    Virology Journal 11/2010; 7(1):313. DOI:10.1186/1743-422X-7-313 · 2.09 Impact Factor
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    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.
    Archives of Virology 11/2010; 156(2):235-44. DOI:10.1007/s00705-010-0849-z · 2.28 Impact Factor
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    J Michael Day · Laszlo Zsak
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    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.
    Virology 03/2010; 399(1):59-64. DOI:10.1016/j.virol.2009.12.027 · 3.28 Impact Factor
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    ABSTRACT: Turkey astrovirus type-2 (TAstV-2), turkey rotavirus (TRotV), and turkey reovirus (TReoV) have been implicated as possible causes of enteric diseases and poor production in turkeys; however, numerous studies with each individual virus have failed to reproduce the disease as observed in the field. Therefore, in this study we evaluated the pathogenesis of all possible combinations of one, two, or three viruses in comparison to sham inoculates in 3-day-old turkey poults. Body weights were recorded at 2, 4, 7, 10, and 14 days postinoculation (PI) and were decreased in virus-infected turkeys throughout the experiment as compared to sham inoculates. Although not significantly different from the other virus-exposed groups, the poults exposed to all three viruses had the lowest body weights throughout the experiment. Clinical signs, including huddling, diarrhea, and agitation, were only observed in groups exposed to TAstV-2 and/or TRotV. At 4 days PI, birds from each treatment group were necropsied, and pale intestines with watery contents and undigested feed were observed in the groups that were exposed to TRotV + TReoV or TRotV + TAstV-2 and the group exposed to all three viruses. Minimal microscopic lesions were observed in the intestines of turkeys infected with TAstV-2, TReoV, or a combination of both. In the turkeys infected with TRotV, either alone or in combination with other viruses, mild microscopic lesions were found in all sections of the small intestine and viral antigen was identified by immunohistochemical staining in mature enterocytes. No or very mild lesions were observed in other organs with the exception of the bursa of Fabricius, where mild to severe atrophy was observed in all virus-infected poults examined. Cloacal shedding of TAstV-2 and TRotV was evaluated by reverse-transcription PCR testing of cloacal swabs and minimal differences were observed among the treatment groups.
    Avian Diseases 03/2010; 54(1):16-21. DOI:10.1637/9211.1 · 1.11 Impact Factor
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    ABSTRACT: Cerebellar hypoplasia and hydrocephalus were identified in day old broiler chickens showing nervous signs, impaired mobility, and diarrhea. At postmortem examination, brains of chickens were misshapen and cerebellums were smaller than normal. Microscopically, cerebellar folia were reduced in size and irregularly shaped, and the ventricles were widely distended. Affected cerebellums had focal areas along the base of folia where the internal granular cell layer had been lost, and Purkinje cells were disorganized and located within the molecular layer. Parvovirus DNA was detected by polymerase chain reaction in three of nine brains with oligonucleotide primers designed for amplification of chicken and turkey parvoviruses. On the basis of phylogenetic analyses, the detected virus was most closely related to chicken parvoviruses. These findings suggest that a chicken parvovirus might cause a neurologic disease of young chickens characterized by cerebellar hypoplasia and hydrocephalus; however, its role as the cause of the disease remains to be confirmed.
    Avian Diseases 03/2010; 54(1):156-60. DOI:10.1637/8976-070709-Case.1 · 1.11 Impact Factor
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    ABSTRACT: Myocarditis associated with reovirus was diagnosed in 17-day-old, male turkey poults, based on virus isolation, reverse transcriptase-polymerase chain reaction (RT-PCR), demonstration of reovirus antigen in the cytoplasm of mononuclear inflammatory cells and myocytes in the heart by immunohistochemistry (IHC), and reovirus particles in the endoplasmic reticulum of myocytes by transmission electron microscopy (TEM). Clinical signs in the poults included anorexia, growth depression, and increased mortality. Gross lesions in the six poults examined were increased pericardial fluid, mild-to-moderate dilation of right ventricles, pale-yellow myocardium, and ascites. Other lesions in a few birds included mild pulmonary edema, congestion, and pale serosa of the small intestine that had watery contents in their lumens. Microscopically, in the heart, there was mild-to-severe necrosis of myocytes and infiltration of primarily lymphocytes mixed with a few heterophils, macrophages, and occasionally, plasma cells and multinucleated giant cells. There was mild-to-moderate lymphoid depletion in the bursa of Fabricius. Reovirus was isolated from the heart of the turkey poults in chicken-embryo liver cells and was confirmed by RT-PCR, IHC, and TEM. A retrospective search of the laboratory database for cases of myocarditis associated with reovirus in turkeys revealed that this condition has occurred sporadically in California turkey flocks since 1991. This is the first documentation of myocarditis in turkey poults associated with reovirus.
    Avian Diseases 12/2009; 53(4):523-32. DOI:10.1637/9047.1 · 1.11 Impact Factor
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    J Michael Day
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    ABSTRACT: The family Reoviridae is a diverse group of viruses with double-stranded RNA genomes contained within icosahedral, non-enveloped, double-layered protein capsids. Within the Reoviridae, the Orthoreovirus genus includes viruses that infect reptiles, birds and mammals (including humans). Recent sequencing efforts have produced a great deal of new molecular data for the fusogenic orthoreoviruses, a group of reoviruses that induce cell-cell fusion during an infection. This new data has allowed a fresh look at the phylogenetic relationships among the members of the Orthoreovirus genus, and has provided insight into the evolution of orthoreovirus species and species groups. This review mainly focuses on the molecular taxonomy of the fusogenic orthoreoviruses, and aims to provide insight into their relationships with the non-fusogenic orthoreoviruses and other selected Reoviridae genera.
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 08/2009; 9(4):390-400. DOI:10.1016/j.meegid.2009.01.011 · 3.26 Impact Factor
  • Laszlo Zsak · Keith O Strother · J Michael Day
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    ABSTRACT: Comparative sequence analysis of six independent chicken and turkey parvovirus nonstructural (NS) genes revealed specific genomic regions with 100% nucleotide sequence identity. A polymerase chain reaction (PCR) assay with primers targeting these conserved genome sequences proved to be highly specific and sensitive to detecting parvoviruses in experimentally infected chickens. In a nationwide survey, a total of 138 field enteric samples from poultry flocks were tested by PCR for parvovirus presence. Of the tested chicken samples that were collected in 54 farms, 77% showed the presence of parvovirus, while 78% of the turkey samples that were received from 29 farms were parvovirus positive. For the first time, our data clearly demonstrate that parvoviruses are widely distributed in commercial poultry flocks in the United States. The high prevalence of parvovirus infection in birds from enteric disease-affected flocks suggests a potential role of these viruses in the etiology of enteric disease of poultry. Phylogenetic analyses comparing NS gene segments showed that most of the chicken and turkey parvovirus isolates formed separate phylogenetic groups. These findings suggest that the chicken and turkey parvoviruses might have diverged from a common ancestor and have subsequently undergone host-specific adaptation.
    Avian Diseases 04/2009; 53(1):83-8. DOI:10.1637/8464-090308-Reg.1 · 1.11 Impact Factor
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    ABSTRACT: Recently, pathogenesis studies, using genetically distinct turkey-origin reoviruses (TRVs), revealed that poults infected with certain TRV isolates had moderate to severe bursal atrophy, suggesting virus-induced immune dysfunction. In order to characterize the effect of TRV infection on the turkey immune system, classical assays were undertaken to quantify the humoral and cell-mediated immune responses in small Beltsville and broad-breasted white poults infected with the TRV isolate NC/SEP-R44/03. A marked effect on the cutaneous basophil hypersensitivity response, and on the antibody response to Newcastle disease virus (NDV) exposure, was noted in commercial and specific pathogen free (SPF) poults inoculated with NC/SEP-R44/03 at three days of age. Moderate to severe bursal atrophy, similar to that noted previously in SPF poults, occurred in commercial poults inoculated at three days of age. This immune dysfunction and bursal atrophy was not present in commercial poults inoculated at three weeks of age.
    Avian Diseases 10/2008; 52(3):387-91. DOI:10.1637/8190-120607-Reg · 1.11 Impact Factor
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    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.
    Avian Diseases 06/2008; 52(2):235-44. DOI:10.1637/8316-817408-DIGEST.1 · 1.11 Impact Factor
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    ABSTRACT: The pathogenicity of three different type 2 turkey astroviruses (TAstV-2) was studied in specific pathogen free turkeys. These viruses differ based on sequence analysis of the capsid gene. Poults were inoculated at 2 days of age and examined during 14 days for clinical signs and virus shedding. All inoculated poults presented signs of enteric disease including diarrhoea and growth depression. Virus presence and shedding was detected by real-time reverse transcriptase-polymerase chain reaction from intestinal contents and cloacal swabs collected at 3, 7 and 14 days post-inoculation. Viraemia was also confirmed by this method. Common lesions observed at necropsy were dehydration; distended intestines filled with watery contents and undigested feed, and dilated caeca with foamy contents. Microscopic lesions present in the intestines consisted of mild crypt hyperplasia, villous atrophy and lymphocytic infiltration, and were most common in the jejunum. Presence of the viruses was demonstrated by immunohistochemistry and by in situ hybridization in both villi and crypt enterocytes in the jejunum and, less frequently, the duodenum, ileum and caeca. Mild lesions consisting mainly of lymphocytic infiltration were also observed in other organs including the pancreas, liver, spleen and kidneys. Mild to moderate bursal atrophy occurred in all TAstV-2-infected poults examined; however, no specific viral staining was observed in this organ or any other tissues examined apart from the intestines. In conclusion, TAstV-2 viruses with variant capsids produce a similar enteric disease in young turkeys and may also affect the immune system of the birds by causing bursal lymphoid depletion.
    Avian Pathology 05/2008; 37(2):193-201. DOI:10.1080/03079450801932200 · 2.04 Impact Factor
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    ABSTRACT: Based on previous reports characterizing the turkey-origin avian reovirus (TRV) sigmaB (sigma2) major outer capsid protein gene, the TRVs may represent a new group within the fusogenic orthoreoviruses. However, no sequence data from other TRV genes or genome segments has been reported. The sigmaC protein encoded by the avian reovirus S1 genome segment is the cell attachment protein and a major antigenic determinant for avian reovirus. The chicken reovirus S1 genome segment is well characterized and is well conserved in viruses from that species. This report details the amplification, cloning and sequencing of the entire S1 genome segment from two and the entire coding sequences of the sigmaC, p10 and p17 genes from an additional five TRVs. Sequence analysis reveals that of the three proteins encoded by the TRV S1 genome segment, sigmaC shares at most 57% amino acid identity with sigmaC from the chicken reovirus reference strain S1133, while the most similar p10 and p17 proteins share 72% and 61% identity, respectively, with the corresponding S1133 proteins. The most closely related mammalian reovirus, the fusogenic Nelson Bay reovirus, encodes a sigmaC protein that shares from 25% to 28% amino acid identity with the TRV sigmaC proteins. This report supports the earlier suggestion that the TRVs are a separate virus species within the Orthoreovirus genus, and may provide some insight into TRV host specificity and pathogenesis.
    Virus Genes 11/2007; 35(2):235-42. DOI:10.1007/s11262-006-0044-1 · 1.84 Impact Factor

Publication Stats

468 Citations
39.69 Total Impact Points

Institutions

  • 2008–2013
    • Agricultural Research Service
      ERV, Texas, United States
  • 2009
    • United States Department of Agriculture
      • Agricultural Research Service (ARS)
      Washington, D. C., DC, United States