@article{faiz_cortes_guy_fletcher_west_montiel_gimeno_2016, title={Early infection with Marek's disease virus can jeopardize protection conferred by laryngotracheitis vaccines: a method to study MDV-induced immunosuppression}, volume={45}, ISSN={["1465-3338"]}, DOI={10.1080/03079457.2016.1191618}, abstractNote={ABSTRACT Marek’s disease virus (MDV) is a herpesvirus that induces lymphomas and immunosuppression in chickens. MDV-induced immunosuppression (MDV-IS) is divided into two phases: early-MDV-IS occurring mainly in chickens lacking maternal antibodies (MAb) against MDV and associated with lymphoid organ atrophy; and late-MDV-IS occurring once MDV enters latency and during tumour development. Our objectives were to document the impact of late-MDV-IS on commercial poultry (meat-type chickens bearing MAb against MDV and that were vaccinated or unvaccinated against MD) and to optimize a model to study late-MDV-IS under laboratory conditions. The impact of late-MDV-IS was evaluated by assessing the effect of early infection (day of age) with a very virulent plus MDV (vv+MDV) on the efficacy of chicken-embryo-origin (CEO) infectious laryngotracheitis (ILT) virus vaccine against ILT challenge. The CEO ILT vaccine was administered in water at 14 days of age and ILT virus (ILTV) challenge was done intratracheally at 30 days of age. Development of ILT was monitored by daily evaluation of clinical signs, development of gross and histological lesions in trachea, and quantification of ILTV transcripts in trachea. Infection with vv+MDV strain 648A resulted in total abrogation of protection conferred by the CEO vaccine against ILTV challenge even in chickens vaccinated at 1 day of age with either HVT, HVT+SB-1, or CVI988. Chickens exposed to vv+MDV prior to vaccination with CEO ILTV vaccine had similar (P < 0.05) clinical scores, gross lesions, histopathologic lesion scores, and load of ILTV transcripts in trachea after ILTV challenge, as chickens that were not vaccinated with CEO ILTV vaccine.}, number={6}, journal={AVIAN PATHOLOGY}, author={Faiz, Nik M. and Cortes, Aneg L. and Guy, James S. and Fletcher, Oscar J. and West, Melissa and Montiel, Enrique and Gimeno, Isabel M.}, year={2016}, pages={606–615} }
 @article{marusak_west_davis_fletcher_guy_2012, title={Transmissible Viral Proventriculitis Identified in Broiler Breeder and Layer Hens}, volume={56}, ISSN={0005-2086 1938-4351}, url={http://dx.doi.org/10.1637/10216-042412-case.1}, DOI={10.1637/10216-042412-case.1}, abstractNote={SUMMARY. Transmissible viral proventriculitis (TVP) is a recognized cause of production losses in broiler chickens, but previously it has not been reported in broiler breeder and commercial layer hens. In this study, TVP was identified in broiler breeder and commercial layer hens, 9–20 wk of age, based on histopathologic detection of characteristic microscopic lesions. Microscopic lesions in proventriculi of affected hens consisted of glandular epithelial necrosis, ductal epithelial hyperplasia, replacement of glandular epithelium with ductal epithelium, and diffuse interstitial lymphoid infiltration. Additionally, chicken proventricular necrosis virus (CPNV), a virus previously identified as the etiology of TVP in broiler chickens, was detected in proventriculi of TVP-affected hens using a reverse transcriptase–polymerase chain reaction procedure. The findings identify TVP as a potential cause of production losses in broiler breeder and commercial layer hens and provide additional evidence for etiologic involvement in TVP by CPNV.}, number={4}, journal={Avian Diseases}, publisher={American Association of Avian Pathologists (AAAP)}, author={Marusak, Rosemary A. and West, Melissa A. and Davis, James F. and Fletcher, Oscar J. and Guy, James S.}, year={2012}, month={Dec}, pages={757–759} }
 @article{guy_west_fuller_marusak_shivaprasad_davis_fletcher_2011, title={Detection of Chicken Proventricular Necrosis Virus (R11/3 Virus) in Experimental and Naturally Occurring Cases of Transmissible Viral Proventriculitis with the Use of a Reverse Transcriptase-PCR Procedure}, volume={55}, ISSN={["0005-2086"]}, DOI={10.1637/9586-102110-reg.1}, abstractNote={SUMMARY. A reverse-transcriptase–polymerase-chain-reaction (RT-PCR) procedure was evaluated for detection of chicken proventricular necrosis virus (CPNV) in transmissible viral proventriculitis (TVP) –affected chickens. The RT-PCR procedure was compared with indirect immunofluorescence (IFA) and virus isolation for detection of CPNV in experimentally infected chickens. Microscopic lesions characteristic of TVP were detected on days 5–35 postexposure (PE) in CPNV-infected chickens; CPNV was detected by RT-PCR on days 3–14 PE in freshly collected proventriculi, and on days 1–14 PE in formalin-fixed paraffin-embedded (FFPE) proventriculi. CPNV was detected in proventriculi of experimentally infected chickens by IFA on days 3–10 PE, and by virus isolation on days 1–14 PE. With IFA used as a reference, sensitivity of the RT-PCR procedure with freshly collected and FFPE proventriculi was 88% and 100%, respectively; specificity was 83% and 86%, respectively. Proventriculi (FFPE) obtained from suspect TVP cases (n  =  19) were evaluated for presence of CPNV by RT-PCR and microscopic lesions consistent with TVP. CPNV was detected by RT-PCR in proventriculi from 8/11 TVP (+) cases (24/36 tissue sections). TVP (+) cases were defined by microscopic lesions characteristic of TVP; CPNV was not detected in proventriculi (0/8 cases, 0/32 tissue sections) in the absence of these lesions. The association between presence of TVP-characteristic microscopic lesions and presence of CPNV was highly significant (P  =  0.0014). These findings indicate the utility of the RT-PCR procedure for detection of CPNV and provide additional evidence for an etiologic role for this virus in TVP.}, number={1}, journal={AVIAN DISEASES}, author={Guy, James S. and West, Melissa A. and Fuller, Frederick J. and Marusak, Rosemary A. and Shivaprasad, H. L. and Davis, James L. and Fletcher, Oscar J.}, year={2011}, month={Mar}, pages={70–75} }
 @article{guy_west_fuller_2011, title={Physical and Genomic Characteristics Identify Chicken Proventricular Necrosis Virus (R11/3 Virus) as a Novel Birnavirus}, volume={55}, ISSN={["1938-4351"]}, DOI={10.1637/9504-081610-reg.1}, abstractNote={SUMMARY. Chicken proventricular necrosis virus (CPNV), isolate R11/3, previously was isolated from transmissible viral proventriculitis–affected chickens and was determined to be the likely etiology of this disease. CPNV was identified as a birnavirus on the basis of virion size and morphology (icosahedral, approximately 75 nm in diameter, nonenveloped); buoyant density in cesium chloride (1.32 g/ml); a genome comprising bisegmented, double-stranded RNA (approximately 3.8 and 3.4 kilobase pairs); and nucleotide sequence analyses. Nucleotide sequencing of CPNV RNA, segment B, identified a single large open reading frame that encodes a 903–amino acid protein. The 903–amino acid protein was identified as the putative VP1, the viral RNA-dependent RNA polymerase (RdRp), on the basis of sequence homologies with other birnavirus VP1 proteins. The CPNV VP1 possessed the unique permuted RdRp sequence motif arrangement characteristic of birnaviruses; however, phylogenetic analyses based on VP1 demonstrated that CPNV is deeply divergent from other birnaviruses.}, number={1}, journal={AVIAN DISEASES}, author={Guy, James S. and West, Melissa A. and Fuller, Frederick J.}, year={2011}, month={Mar}, pages={2–7} }