@article{criollo_john_gaghan_fletcher_thachil_crespo_kulkarni_2024, title={Characterization of immune responses and immunopathology in turkeys experimentally infected with clostridial dermatitis-producing strains of Clostridium septicum}, volume={269}, ISSN={["1873-2534"]}, DOI={10.1016/j.vetimm.2024.110717}, abstractNote={Clostridium septicum is one of the major causative agents of clostridial dermatitis (CD), an emerging disease of turkeys, characterized by sudden deaths and necrotic dermatitis. Despite its economic burden on the poultry industry, the immunopathological changes and pathogen-specific immune responses are poorly characterized. Here, we used three strains of C. septicum, namely Str. A1, Str. B1 and Str. C1, isolated from CD field outbreaks, to experimentally infect turkeys to evaluate local (skin and muscle) and systemic (spleen) pathological and immunological responses. Results showed that while all three strains produced an acute disease, Str. A1 and B1 caused significantly higher mortality when compared to Str. C1. Gross and histopathology evaluation showed that birds infected with Str. A1 and B1 had severe inflammatory, edematous, granulomatous and necrotic lesions in the skin, muscle and spleen, while these lesions produced by Str. C1 were relatively less severe and mostly confined to skin and/or muscle. Immune gene expression in these tissues showed that Str. B1-infected birds had significantly higher expression of interleukin (IL)−1β, IL-6 and interferon (IFN)γ genes compared to uninfected control, suggesting a robust inflammatory response both locally as well as systemically. The transcription of IL-1β and IFNγ in the muscle or spleen of Str. A1-infected birds and IL-1β in the skin of Str. C1-infected group was also significantly higher than control. Additionally, Str. A1 or B1-infected groups also had significantly higher IL-4 transcription in these tissues, while birds infected with all three strains developed C. septicum-specific serum antibodies. Furthermore, splenic cellular immunophenotyping in the infected turkeys showed a marked reduction in CD4+ cells. Collectively, it can be inferred that host responses against C. septicum involve an acute inflammatory response along with antibody production and that the disease severity seem to depend on the strain of C. septicum involved in CD in turkeys.}, journal={VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY}, author={Criollo, Valeria and John, Feba Ann and Gaghan, Carissa and Fletcher, Oscar J. and Thachil, Anil and Crespo, Rocio and Kulkarni, Raveendra R.}, year={2024}, month={Mar} }
 @article{kulkarni_gaghan_gorrell_fletcher_2023, title={Mucosal and systemic lymphoid immune responses against Clostridium perfringens strains with variable virulence in the production of necrotic enteritis in broiler chickens}, volume={1}, ISSN={["1465-3338"]}, DOI={10.1080/03079457.2022.2154195}, abstractNote={ABSTRACT Necrotic enteritis (NE), caused by Clostridium perfringens, is an economically important disease of chickens. Although NE pathogenesis is moderately well studied, the host immune responses against C. perfringens are poorly understood. The present study used an experimental NE model to characterize lymphoid immune responses in the caecal tonsils (CT), bursa of Fabricius, Harderian gland (HG) and spleen tissues of broiler chickens infected with four netB+ C. perfringens strains (CP1, CP5, CP18, and CP26), of which CP18 and CP26 strains also carried the tpeL gene. The gross and histopathological lesions in chickens revealed CP5 to be avirulent, while CP1, CP18, and CP26 strains were virulent with CP26 being “very virulent”. Gene expression analysis showed that, while the virulent strains induced a significantly upregulated expression of pro-inflammatory IL-1β gene in CT, the CP26-infected birds had significantly higher CT transcription of IFNγ and IL-6 pro-inflammatory genes compared to CP5-infected or uninfected chickens. Furthermore, CP26 infection also led to significantly increased bursal and HG expression of the anti-inflammatory/regulatory genes, IL-10 or TGFβ, compared to control, CP5 and CP1 groups. Additionally, the splenic pro- and anti-inflammatory transcriptional changes were observed only in the CP26-infected chickens. An antibody-mediated response, as characterized by increased IL-4 and/or IL-13 transcription and elevated IgM levels in birds infected with virulent strains, particularly in the CP26-infected group compared to uninfected controls, was also evident. Collectively, our findings suggest that lymphoid immune responses during NE in chickens are spatially regulated such that the inflammatory responses against C. perfringens depend on the virulence of the strain.}, journal={AVIAN PATHOLOGY}, author={Kulkarni, Raveendra R. and Gaghan, Carissa and Gorrell, Kaitlin and Fletcher, Oscar J.}, year={2023}, month={Jan} }
 @article{adams_ruiz-jimenez_fletcher_gall_crespo_2022, title={Image analysis for Eimeria oocyst counts and classification}, volume={31}, ISSN={["1537-0437"]}, DOI={10.1016/j.japr.2022.100260}, abstractNote={The McMaster counting technique is the standard method used to enumerate coccidia oocysts in poultry flocks. It also allows for speciation of coccidia according to the size of their oocysts. The McMaster is a manual technique, which can be tedious and time-consuming. In this study, we present a method for quantification and classification of Eimeria using the image processing program, FIJI ImageJ (ImageJ). We compared 34 litter samples from different poultry houses. Oocysts were loaded and floated into a McMaster chamber, where they were counted manually and by ImageJ. When the software settings were used to count all oocysts without size consideration, statistical differences were found between the two techniques; however, when the parameters were set to identify specific oocyst size and cirularity, no significant statistical differences were found between results from McMaster counting technique and ImageJ. Taking the sum of the individual oocysts sizes (small, medium, and large) provided a total count that was similar to the total count obtained using the manual method. Furthermore, no statistical differences were found in the counts of Eimeria sp. oocysts by either method. However, a small but statistically significant difference was found between counts obtained using the two methods for the medium size oocysts (tentatively classified as E. necatrix, E. precox, and E. tenella together). Overall, automatic counting using ImageJ was demonstrated to be an accurate and rapid method for counting and speciating Eimeria.}, number={3}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Adams, Daniel S. and Ruiz-Jimenez, Fernando and Fletcher, Oscar J. and Gall, Sezny and Crespo, Rocio}, year={2022}, month={Sep} }
 @article{jones_rives_fletcher_martin_2020, title={Histomoniasis outbreaks in commercial turkeys in the southeastern United States: Proximity of broiler breeder farms as a potential risk factor in disease development}, volume={29}, ISSN={["1537-0437"]}, DOI={10.1016/j.japr.2019.12.006}, abstractNote={Histomoniasis, an infectious disease of turkeys and other gallinaceous birds, has significant impacts on the health and welfare of infected turkey flocks. No preventatives or treatments for the disease are available. In the current study, the proximity of broiler breeder farms as a potential risk factor for histomoniasis in grow-out tom flocks was assessed using 2015 retrospective data provided by a commercial turkey integrator located in North and South Carolina. Company grow-out tom farms were grouped into potential “at risk” categories based on distance from broiler breeder farms. Presence of a broiler breeder flock within 1 mile of a grow-out tom farm placed that tom farm at a higher relative risk (RR) (RR = 3.45; 95% CI = 1.7519–6.8121; P-value = 0.0196) for occurrence of histomoniasis. There was no increased RR of histomoniasis at tom farms in distance categories beyond 1 mile from a broiler breeder flock. These results are consistent with variable transmission of Heterakis eggs harboring Histomonas from broiler breeder houses to susceptible turkey farms based on distance between farms.}, number={2}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Jones, R. E. and Rives, D. V. and Fletcher, O. J. and Martin, M. P.}, year={2020}, month={Jun}, pages={496–501} }
 @article{rahimi_kathariou_fletcher_grimes_2019, title={Effect of a direct-fed microbial and prebiotic on performance and intestinal histomorophology of turkey poults challenged with Salmonella and Campylobacter}, volume={98}, ISSN={["1525-3171"]}, DOI={10.3382/ps/pez436}, abstractNote={Salmonella and Campylobacter are leading human foodborne pathogens commonly associated with poultry and poultry products, and several methods to control these pathogens have been applied to poultry production. This study was conducted to evaluate the effect of CALSPORIN, (CSP), a direct-fed microbial (DFM), and yeast cell wall (Saccharomyces cervisiae, IMW50, a mannanoligosaccharide (MOS)-based prebiotic, on performance, levels of Salmonella and Campylobacter in the feces, and intestinal histomorphometry in turkey poults. A 21-day battery cage study was conducted using 4 dietary treatments, including: an unsupplemented basal diet (corn and soybean-based) as negative control (NC); basal diet supplemented with 0.05% DFM; basal diet supplemented with 0.05% MOS; and basal diet supplemented with 0.05% mixture of DFM and MOS at equal proportions. Female Large White turkey poults (n = 336) were randomly distributed in 6 electrically-heated battery cages with 4 treatments and 12 replicates per treatment (7 poults per replicate pen). The first 16 pens were not inoculated with bacteria, while poults in pens 17 to 32 were orally challenged at day 7 with 105 CFU Salmonella Heidelberg and the poults in pens 33 to 48 were orally challenged at day 7 with 105 CFU Campylobacter jejuni. Feed consumption, body weight, and feed conversion ratio were measured weekly and at the end of the experiment. At day 21, fresh fecal samples from each pen were collected for Salmonella and Campylobacter enumeration and ileal tissue samples were collected from 1 bird per pen for histomorphology examination. DFM and MOS supplementation was accompanied with reduced levels of Salmonella shed by the treated birds compared to the control group, and with increased body weight (P ≤ 0.05). The surface area of villi increased in the MOS-supplemented group compared to the control group (P ≤ 0.05). There was a significant difference in V:C ratio between supplemented groups and control group (P ≤ 0.05). Based on these results, there is potential for CALSPORIN and IMW50 to reduce Salmonella shedding in feces, enhance ileal mucosal health, and improve growth performance of turkey poults.}, number={12}, journal={POULTRY SCIENCE}, author={Rahimi, Shaban and Kathariou, Sophia and Fletcher, Oscar and Grimes, Jesse L.}, year={2019}, month={Dec}, pages={6572–6578} }
 @article{mocka_stern_fletcher_anderson_petitte_mozdziak_2017, title={Chemoprevention of spontaneous ovarian cancer in the domestic hen}, volume={96}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps/pew422}, DOI={10.3382/ps/pew422}, abstractNote={&NA; The hen is an attractive animal model for in vivo testing of agents that thwart ovarian carcinogenesis because ovarian cancer in the domestic hen features clinical and molecular alterations that are similar to ovarian cancer in humans, including a high incidence of p53 mutations. The objective of the study was to test the potential ovarian cancer chemopreventive effect of the p53 stabilizing compound CP‐31398 on hens that spontaneously present the ovarian cancer phenotype. Beginning at 79 wk of age, 576 egg‐laying hens (Gallus domesticus) were randomized to diets containing different amounts of CP‐31398 for 94 wk, 5 d, comprising a control group (C) (n = 144), which was fed a diet containing 0 ppm (mg/kg) of CP‐31398; a low‐dose treatment (LDT) group (n = 144), which was fed a diet containing 100 ppm of CP‐31398; a moderate‐dose treatment (MDT) group (n = 144) which was fed a diet containing 200 ppm of CP‐31398; and a high‐dose treatment (HDT) group (n = 144), which was fed a diet containing 300 ppm of CP‐31398. Hens were killed at 174 wk of age to determine the incidence of ovarian and oviductal adenocarcinomas. Whereas the incidence of localized and metastatic ovarian cancers in the MDT and HDT groups was significantly lower (up to 77%) compared to levels in the C and LDT groups (P < 0.05), the incidence of oviductal cancer was unaffected by CP‐31398. CP‐31398 appears to be an effective tool for chemoprevention against ovarian malignancies, but does not appear to affect oviductal malignancies.}, number={6}, journal={Poultry Science}, publisher={Elsevier BV}, author={Mocka, E.H. and Stern, R.A. and Fletcher, O.J. and Anderson, K.E. and Petitte, J.N. and Mozdziak, P.E.}, year={2017}, month={Jun}, pages={1901–1909} }
 @article{faiz_cortes_guy_fletcher_cimino_gimeno_2017, title={Evaluation of factors influencing the development of late Marek's disease virus-induced immunosuppression: virus pathotype and host sex}, volume={46}, ISSN={["1465-3338"]}, DOI={10.1080/03079457.2017.1290214}, abstractNote={ABSTRACT Marek’s disease virus (MDV) is a herpesvirus that induces lymphoma and immunosuppression in chickens. MDV-induced immunosuppression (MDV-IS) is complex and can be divided into two phases: early-MDV-IS associated with cytolytic infection in the lymphoid organs in chickens lacking maternal antibodies against MDV (MAbs) and late-MDV-IS that appears later in the pathogenesis and occurs even in chickens bearing MAbs. We have recently developed a model to reproduce late-MDV-IS under laboratory conditions. This model evaluates late-MDV-IS indirectly by assessing the effect of MDV infection on the efficacy of infectious laryngotracheitis (ILT) vaccines against challenge with ILT virus. In the present study, we have used this model to investigate the role of two factors (MDV pathotype and host sex) on the development of late-MDV-IS. Five MDV strains representing three different pathotypes: virulent (vMDV; 617A, GA), very virulent (vvMDV; Md5), and very virulent plus (vv+MDV; 648A, 686), were evaluated. Only vv+ strains were able to induce late-MDV-IS. An immunosuppression rank (IS-rank) was established based on the ability of MDV to reduce the efficacy of chicken embryo origin vaccine (values go from 0 to 100, with 100 being the highest immunosuppressive ability). The IS-rank of the evaluated MDV strains ranged from 5.97 (GA) to 20.8 (617A) in the vMDV strains, 5.97 to 16.24 in the vvMDV strain Md5, and 39.08 to 68.2 in the vv+ strains 648A and 686. In this study both male and female chickens were equally susceptible to MDV-IS by vv+MDV 686. Our findings suggest that late-MDV-IS is a unique feature of vv+ strains.}, number={4}, journal={AVIAN PATHOLOGY}, author={Faiz, Nik M. and Cortes, Aneg L. and Guy, James S. and Fletcher, Oscar J. and Cimino, Thomas and Gimeno, Isabel M.}, year={2017}, pages={376–385} }
 @article{stafford_lambert_zyskowski_engfehr_fletcher_clark_tiwary_gulde_sample_2016, title={Dietary toxicity of soluble and insoluble molybdenum to northern bobwhite quail (Colinus virginianus)}, volume={25}, ISSN={["1573-3017"]}, DOI={10.1007/s10646-015-1587-5}, abstractNote={Limited data are available on the effects of molybdenum (Mo) on avian wildlife, which impairs evaluation of ecological exposure and risk. While Mo is an essential trace nutrient in birds, little is known of its toxicity to birds exposed to molybdenum disulfide (MoS2), the predominant form found in molybdenite ore. The chemical form and bioavailability of Mo is important in determining its toxicity. Avian toxicity tests typically involve a soluble form of Mo, such as sodium molybdate dihydrate (SMD, Na2MoO4·2H2O); however MoS2 is generally insoluble, with low bioaccessibility under most environmental conditions. The current study monitored survival and general health (body weight and food consumption) of 9-day old northern bobwhite exposed to soluble Mo (SMD) and ore-related Mo (MoS2) in their diet for 30 days. Toxicity and bioavailability (e.g. tissue distribution) of the two Mo forms were compared. Histopathology evaluations and serum, kidney, liver, and bone tissue sample analyses were conducted. Copper, a nutrient integrally associated with Mo toxicity, was also measured in the diet and tissue. No treatment-related mortality occurred and no treatment-related lesions were recorded for either Mo form. Tissue analyses detected increased Mo concentrations in serum, kidney, liver, and bone tissues following exposure to SMD, with decreasing concentrations following a post-exposure period. For the soluble form, a No-Observed-Adverse-Effect Concentration (NOAEC) of 1200 mg Mo as SMD/kg feed (134 mg SMD/kg body weight/day) was identified based on body weight and food consumption. No adverse effects were observed in birds exposed to MoS2 at the maximum dose of 5000 mg MoS2/kg feed (545 mg MoS2/kg body weight/day). These results show that effects associated with MoS2, the more environmentally prevalent and less bioavailable Mo form, are much less than those observed for SMD. These data should support more realistic representations of exposure and risks to avian receptors from environmental Mo.}, number={2}, journal={ECOTOXICOLOGY}, author={Stafford, Jennifer M. and Lambert, Charles E. and Zyskowski, Justin A. and Engfehr, Cheryl L. and Fletcher, Oscar J. and Clark, Shanna L. and Tiwary, Asheesh and Gulde, Cynthia M. and Sample, Bradley E.}, year={2016}, month={Mar}, pages={291–301} }
 @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{harris_fletcher_anderson_petitte_kopelovich_mozdziak_2014, title={Epithelial Cell Tumors of the Hen Reproductive Tract}, volume={58}, ISSN={["1938-4351"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84896380321&partnerID=MN8TOARS}, DOI={10.1637/10643-082313-reg.1}, abstractNote={SUMMARY There is a paucity of preclinical models that simulate the development of ovarian tumors in humans. At present, the egg-laying hen appears to be the most promising model to study the spontaneous occurrence of ovarian tumors in the clinical setting. Although gross classification and histologic grade of tumors have been used prognostically in women with ovarian tumors, there is currently no single system that is universally used to classify reproductive tumors in the hen. Four hundred and one 192-wk-old egg-laying hens were necropsied to determine the incidence of reproductive tumors using both gross pathology and histologic classification. Gross pathologic classifications were designated as follows: birds presenting with ovarian tumors only (class 1), those presenting with oviductal and ovarian tumors (class 2), those with ovarian and oviductal tumors that metastasized to the gastrointestinal tract (class 3), those with ovarian and oviductal tumors that metastasized to the gastrointestinal tract and other distant organs (class 4), those with oviductal tumors only (class 5), those with oviductal tumors that metastasized to other organs with no ovarian involvement (class 6), and those with ovarian tumors that metastasized to other organs with no oviductal involvement (class 7), including birds with gastrointestinal tumors and no reproductive involvement (GI only) and those with no tumors (normal). Histopathologic classifications range from grades 1 to 3 and are based on mitotic developments and cellular differentiation. An updated gross pathology and histologic classification systems for the hen reproductive malignancies provides a method to report the range of reproductive tumors revealed in a flock of aged laying hens. RESUMEN Tumores de células epiteliales del tracto reproductivo de la gallina. Hay una escasez de modelos preclínicos que simulen el desarrollo de los tumores de ovario en humanos. En la actualidad, la gallina de postura parece ser el modelo más prometedor para estudiar la aparición espontánea de tumores en el ovario en el ámbito clínico. Aunque la clasificación macroscópica y el grado histológico de los tumores se han utilizado para realizar el pronóstico en mujeres con tumores de ovario, no existe actualmente ningún sistema que se utilice universalmente para clasificar tumores reproductivos en la gallina. Se realizó la necropsia de 401 gallinas de postura de 192 semanas de edad para determinar la incidencia de los tumores del aparato reproductor utilizando tanto patología macroscópica y clasificación histológica. Las clasificaciones patológicas macroscópicas fueron designadas de la siguiente manera: las aves que presentaron únicamente tumores de ovario (clase 1), los que presentan tumores de ovario y oviducto (clase 2), aquellos con tumores de ovario y oviducto y con metástasis en el tracto gastrointestinal (clase 3), las aves que tienen tumores de ovario y oviducto, con metástasis en el tracto gastrointestinal y otros órganos distantes (clase 4), las aves que tienen tumores del oviducto solamente (clase 5), aquellas con tumores del oviducto con metástasis a otros órganos sin la participación de ovario (clase 6), y las aves que tienen tumores de ovario con metástasis a otros órganos sin la participación del oviducto (clase 7), incluidas las aves con tumores gastrointestinales y sin compromiso del aparato reproductivo (sólo tracto gastrointestinal) y las aves que no tienen tumores (normales). Las clasificaciones histopatológicas tuvieron un rango que va desde los grados 1 a 3, y se basaron en el desarrollo de mitosis y diferenciación celular. Una descripción patológica macroscópica actualizada y los sistemas de clasificación histológica de los tumores malignos reproductivos de la gallina proporcionan un método para reportar la gama de tumores reproductivos detectados en una parvada de gallinas ponedoras de edad.}, number={1}, journal={Avian Diseases}, author={Harris, E.A. and Fletcher, O.J. and Anderson, K.E. and Petitte, J.N. and Kopelovich, L. and Mozdziak, P.E.}, year={2014}, month={Mar}, pages={95–101} }
 @article{davis_kulkarni_fletcher_2013, title={Reovirus Infections in Young Broiler Chickens}, volume={57}, ISSN={["1938-4351"]}, DOI={10.1637/10515-021313-case.1}, abstractNote={SUMMARY Selected 10-to-21-day-old broiler chickens from flocks undergoing runting-stunting syndrome were found to have significant pancreatic damage, grossly and histologically. Six reoviruses, with sequences that varied, both from each other and from S1133 reovirus, were isolated from these pancreases and from pancreases of specific-pathogen-free leghorn sentinels placed on two of the broiler farms for 7 days. RESUMEN Reporte de Caso—Infecciones por reovirus en pollos de engorde jóvenes. Se encontró daño pancreático significativo macroscópico y microscópicamente en pollos de engorde de 10 a 21 de edad seleccionados por bajo crecimiento en parvadas con síndrome de mala absorción. Se aislaron seis reovirus, con secuencias que variaron tanto unos de otros como con respecto a la de cepa S1133, a partir del páncreas de las aves afectadas y del páncreas de aves Leghorn libres de patógenos específicos que fueron alojadas como centinelas en dos granjas de pollos de engorde por siete días.}, number={2}, journal={AVIAN DISEASES}, author={Davis, James F. and Kulkarni, Arun and Fletcher, Oscar}, year={2013}, month={Jun}, pages={321–325} }
 @article{davis_kulkarni_fletcher_2012, title={Myocarditis in 9- and 11-Day-Old Broiler Breeder Chicks Associated with a Reovirus Infection}, volume={56}, ISSN={["0005-2086"]}, DOI={10.1637/10267-060712-case.1}, abstractNote={SUMMARY. Nine- and 11-day-old male broiler breeder chicks from a flock with excessively high mortality were found to have ascites, fibrotic and necrotic livers, and round, thin-walled hearts. Virus isolation on liver homogenates and sequencing of PCR products of the isolate identified a reovirus whose sequence varied from sequences of other published reoviruses. Histopathology supported a diagnosis of reovirus-associated myocarditis and myocardial necrosis. This virus was possibly transmitted vertically from the primary breeder flock. RESUMEN. Reporte de Caso—Miocarditis en pollitos reproductores pesados de 9 y 11 días de edad asociada con una infección por reovirus. Pollitos reproductores pesados de nueve y 11 días de edad, procedentes de una parvada con mortalidad excesivamente alta, mostraron ascitis, hígado fibrótico y necrótico, y corazones redondos, con paredes delgadas. Mediante el aislamiento viral de homogeneizados de hígado y la secuenciación de los productos PCR se identificó un reovirus cuya secuencia varía de las secuencias de otros reovirus publicados. La histopatología confirmó el diagnóstico de miocarditis y necrosis del miocardio asociada con reovirus. Este virus posiblemente se transmitió verticalmente, de la parvada de reproductores.}, number={4}, journal={AVIAN DISEASES}, author={Davis, James F. and Kulkarni, Arun and Fletcher, Oscar}, year={2012}, month={Dec}, pages={786–790} }
 @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{robbins_ye_fletcher_2011, title={Identification of Ascaridia numidae in Guinea Fowl (Numida meleagris) and Association with Elevated Mortality}, volume={55}, ISSN={["1938-4351"]}, DOI={10.1637/9587-102110-case.1}, abstractNote={SUMMARY. An outbreak of ascaridiasis occurred in 10-wk-old guinea fowl (Numida meleagris) on a commercial farm. Birds had exhibited elevated mortality (11.66%) in the previous week, as well as increased water consumption, weakness, anorexia, and stunted growth. Numerous nematodes, occasionally occluding the intestinal lumen, were present in the jejunum and ileum and were identified as Ascaridia numidae based on microscopic morphology. Ribosomal DNA 18S and 28S D3 sequences of the nematode were deposited into GenBank and found to be most similar to Ascaridia galli and Toxocara vitulorum, respectively; sequences for A. numidae had not been previously reported. Treatment with piperazine sulfate significantly reduced the number of adult worms in the intestines, greatly decreased eggs per gram of feces, relieved clinical signs in the flock, and returned the flock mortality back to expected levels. All findings implicate A. numidae as the cause of elevated mortality in this flock.}, number={1}, journal={AVIAN DISEASES}, author={Robbins, Kabel M. and Ye, Weimin and Fletcher, Oscar J.}, year={2011}, month={Mar}, pages={151–154} }
 @article{behnke_fletcher_2011, title={Macrorhabdus ornithogaster (Megabacterium) Infection in Adult Hobby Chickens in North America}, volume={55}, ISSN={["0005-2086"]}, DOI={10.1637/9569-100710-case.1}, abstractNote={Abstract A field investigation was conducted on a flock of adult hobby chickens showing intermittent signs of enteritis. Roosters examined in the initial field visit and postmortem had cecal worms, roundworms, tetratrichomonads, and coccidiosis. Macrorhabdus ornithogaster was diagnosed histologically in the mucosal isthmus of the proventriculus and ventriculus. Three roosters and two hens were examined in a follow-up investigation of the flock conducted 9 days later. Macrorhabdus ornithogaster was confirmed in one hen.}, number={2}, journal={AVIAN DISEASES}, author={Behnke, Elena L. and Fletcher, Oscar J.}, year={2011}, month={Jun}, pages={331–334} }
 @article{martin_wineland_fletcher_barnes_2011, title={Selected Blood Chemistry Values in Mobility-Impaired Broiler Breeder Hens with Suspected Calcium Tetany Using the i-STAT (R) Handheld Clinical Analyzer}, volume={55}, ISSN={["0005-2086"]}, DOI={10.1637/9566-100610-reg.1}, abstractNote={SUMMARY. Calcium tetany is a poorly defined disease of broiler breeder hens that results from acute hypocalcemia. It is characterized by impaired mobility, increased mortality, and absence of gross lesions that would explain the impaired mobility. To evaluate if hens with impaired mobility had calcium tetany or other abnormalities, blood values from normal and affected hens were determined using the i-STAT® handheld clinical analyzer. Three flocks were evaluated weekly prior to peak production (range 25–30 wk of age) comparing normal hens to hens with clinically apparent calcium tetany. Calcium tetany suspect (CaTS) hens from four additional flocks were also evaluated. Significant hypocalcemia (P < 0.001) was observed in CaTS hens (average  =  1.14 mmol/L ionized calcium [iCa]) compared to normal hens (average  =  1.53 mmol/L iCa) in only one of three flocks sampled weekly. Clinically affected hens from one of the other four flocks also had hypocalcemia. Blood value abnormalities in mobility-impaired hens without hypocalcemia included hypernatremia. Findings in this study indicate calcium tetany is one cause of impaired mobility in breeder hens, but mobility impairment without hypocalcemia can also occur. Calcium tetany should be confirmed by finding significantly decreased levels of iCa in the blood, as diagnosis based on clinical presentation and necropsy results can be inaccurate. The i-STAT® handheld clinical analyzer is an efficient, relatively low-cost method to determine iCa and other blood chemistry values that may be associated with impaired mobility in broiler breeder hens.}, number={3}, journal={AVIAN DISEASES}, author={Martin, Michael P. and Wineland, Michael and Fletcher, Oscar J. and Barnes, H. John}, year={2011}, month={Sep}, pages={340–345} }
 @article{hawkridge_wysocky_petitte_anderson_mozdziak_fletcher_horowitz_muddiman_2010, title={Measuring the intra-individual variability of the plasma proteome in the chicken model of spontaneous ovarian adenocarcinoma}, volume={398}, ISSN={["1618-2650"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77957867631&partnerID=MN8TOARS}, DOI={10.1007/s00216-010-3979-y}, abstractNote={The domestic chicken (Gallus domesticus) has emerged as a powerful experimental model for studying the onset and progression of spontaneous epithelial ovarian cancer (EOC) with a disease prevalence that can exceed 35% between 2 and 7 years of age. An experimental strategy for biomarker discovery is reported herein that combines the chicken model of EOC, longitudinal plasma sample collection with matched tissues, advanced mass spectrometry-based proteomics, and concepts derived from the index of individuality (Harris, Clin Chem 20: 1535–1542, 1974). Blood was drawn from 148 age-matched chickens starting at 2.5 years of age every 3 months for 1 year. At the conclusion of the 1 year sample collection period, the 73 birds that remained alive were euthanized, necropsied, and tissues were collected. Pathological assessment of resected tissues from these 73 birds confirmed that five birds (6.8%) developed EOC. A proteomics workflow including in-gel digestion, nanoLC coupled to high-performance mass spectrometry, and label-free (spectral counting) quantification was used to measure the biological intra-individual variability (CVW) of the chicken plasma proteome. Longitudinal plasma sample sets from two birds within the 73-bird biorepository were selected for this study; one bird was considered “healthy” and the second bird developed late-stage EOC. A total of 116 proteins from un-depleted plasma were identified with 80 proteins shared among all sample sets. Analytical variability (CVA) of the label-free proteomics workflow was measured using a single plasma sample analyzed five times and was found to be ≥CVW in both birds for 16 proteins (20%) and in either bird for 25 proteins (31%). Ovomacroglobulin (ovostatin) was found to increase (p < 0.001) over a 6 month period in the late-stage EOC bird providing an initial candidate protein for further investigation.}, number={2}, journal={ANALYTICAL AND BIOANALYTICAL CHEMISTRY}, author={Hawkridge, Adam M. and Wysocky, Rebecca B. and Petitte, James N. and Anderson, Kenneth E. and Mozdziak, Paul E. and Fletcher, Oscar J. and Horowitz, Jonathan M. and Muddiman, David C.}, year={2010}, month={Sep}, pages={737–749} }
 @article{hawkridge_wysocky_petitte_anderson_mozdziak_fletcher_horowitz_muddiman_2010, title={Measuring the intra-individual variability of the plasma proteome in the chicken model of spontaneous ovarian adenocarcinoma (vol 398, pg 737, 2010)}, volume={398}, ISSN={["1618-2642"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-77957848897&partnerID=MN8TOARS}, DOI={10.1007/s00216-010-4107-8}, number={4}, journal={ANALYTICAL AND BIOANALYTICAL CHEMISTRY}, author={Hawkridge, Adam M. and Wysocky, Rebecca B. and Petitte, James N. and Anderson, Kenneth E. and Mozdziak, Paul E. and Fletcher, Oscar J. and Horowitz, Jonathan M. and Muddiman, David C.}, year={2010}, month={Oct}, pages={1835–1835} }
 @article{ley_marusak_vivas_barnes_fletcher_2010, title={Mycoplasma iowae associated with chondrodystrophy in commercial turkeys}, volume={39}, ISSN={["0307-9457"]}, DOI={10.1080/03079451003599276}, abstractNote={Opportunistic observations of and necropsies from selected commercial (meat) turkey flocks revealed skeletal lesions consistent with chondrodystrophy, characterized by leg and vertebral deformities, occurring at very low incidences in turkeys from two primary breeds and various multiplier breeder flocks. Mycoplasma organisms were cultured and identified as Mycoplasma iowae by immunofluorescence and polymerase chain reaction from some of the vertebral lesions but not from leg joints. This is the first detailed description of the gross and microscopic lesions of vertebral chondrodystrophy associated with M. iowae, which should now be considered in the differential diagnosis of turkeys with these lesions.}, number={2}, journal={AVIAN PATHOLOGY}, author={Ley, David H. and Marusak, Rosemary A. and Vivas, Eduardo J. and Barnes, H. John and Fletcher, Oscar J.}, year={2010}, pages={87–93} }
 @article{rahimi_grimes_fletcher_oviedo_sheldon_2009, title={Effect of a direct-fed microbial (Primalac) on structure and ultrastructure of small intestine in turkey poults}, volume={88}, ISSN={0032-5791 1525-3171}, url={http://dx.doi.org/10.3382/ps.2008-00272}, DOI={10.3382/ps.2008-00272}, abstractNote={The effects of dietary supplementation of the direct-fed microbial (DFM) Primalac in mash or crumbled feed on histological and ultrastructural changes of intestinal mucosa was determined in 2 populations of poults; 1 with and 1 without a Salmonella spp. challenge. Three hundred thirty-six 1-d-old female Large White turkey poults were randomly distributed into 8 treatment groups with 6 replicates of 7 poults in each pen. The poults were placed on 1 of 4 dietary treatments in a 2 x 2 x 2 factorial arrangement (mash or crumble feed, with or without DFM, not-challenged or challenged at 3 d of age). The DFM groups were fed a Primalac-supplemented diet from d 1 until the last day of the experiment (d 21). At 3 d of age, 50% of the poults were challenged with 1 mL of 10(10) cfu/ mL of Salmonella spp. (Salmonella enterica serovar Typhimurium, Salmonella Heidelberg, and Salmonella Kentucky) by oral gavage. The inoculated poults were housed in a separate room from nonchallenged controls. Feed and water were provided ad libitum for all birds. At d 21, 1 poult per pen (total of 6 poults per treatment) was randomly selected and killed humanely by cervical dislocation. After necropsy, the small intestine was removed, and tissue samples from duodenum, jejunum, and ileum were taken for light and electron microscopic evaluation. The DFM birds showed increased goblet cell (GC) numbers, total GC area, GC mean size, mucosal thickness, and a greater number of segmented filamentous bacteria compared with controls. Changes in intestinal morphology as observed in this study support the concept that poultry gut health and function, and ultimately bird performance, can be improved by dietary supplementation with DFM products such as Primalac as used in this study.}, number={3}, journal={Poultry Science}, publisher={Oxford University Press (OUP)}, author={Rahimi, S. and Grimes, J. L. and Fletcher, O. and Oviedo, E. and Sheldon, B. W.}, year={2009}, month={Mar}, pages={491–503} }
 @article{osorio_fletcher_dykstra_post_barnes_2007, title={Comb candidiasis affecting roosters in a broiler breeder flock}, volume={51}, ISSN={["0005-2086"]}, DOI={10.1637/0005-2086(2007)51[618:CCARIA]2.0.CO;2}, abstractNote={Abstract A cutaneous mycosis caused by Candida albicans that involved the combs and less frequently the wattles, facial skin, ear lobes, and neck of male broiler breeders is described. Roosters were 35 wk old and housed with hens in two conventional broiler breeder houses on a farm in western North Carolina. Morbidity was approximately 10% in one house and less than 2% in the other house. Mortality and flock fertility were not affected. Three birds from the most affected house were examined. All birds had white adherent material on their combs that presented as crusty patches or lighter diffuse areas. Often, lesions were roughly circular or had a defined margin. Small black scabs were present in a few lesions. Similar but less extensive lesions were located on the wattles, facial skin, ear lobes, and rictus. In one bird, lesions extended down the neck, and they were accompanied by hyperemia and feather loss. Hyperkeratosis with little to no inflammation and intralesional fungi occurring as yeast and pseudohyphae were seen microscopically. High numbers of C. albicans were isolated and identified from the lesions.}, number={2}, journal={AVIAN DISEASES}, author={Osorio, Claudia and Fletcher, Oscar and Dykstra, Michael J. and Post, Karen and Barnes, H. John}, year={2007}, month={Jun}, pages={618–622} }
 @article{osorio_fletcher_abdul-aziz_gonder_tilley_ley_2007, title={Pneumonia of Turkey Breeder Hens Associated with Mycoplasma synoviae}, volume={51}, ISSN={["0005-2086"]}, DOI={10.1637/0005-2086(2007)51[791:POTBHA]2.0.CO;2}, abstractNote={Abstract Turkey breeder hens showed an increase in mortality beginning at 38 wk of age with no other clinical signs or changes in egg production. While no respiratory signs were observed in live turkeys, those that died consistently had gross lesions of pneumonia. Histopathology of lungs revealed serofibrinous bronchopneumonia, lymphofollicular reaction, and other features suggesting a bacterial etiology. However, except for incidental findings, bacteria were not visualized in the sections examined, and none were isolated in meaningful numbers on routine bacteriologic media. At 42 wk of age the flock showed serologic evidence of infection with Mycoplasma synoviae (MS), and MS was identified by both mycoplasma culture and polymerase chain reaction (PCR) procedures in samples from choanal clefts and tracheas. Results of lung histopathology and PCR tests were consistent with a diagnosis of pneumonia caused by MS.}, number={3}, journal={AVIAN DISEASES}, author={Osorio, Claudia and Fletcher, Oscar J. and Abdul-Aziz, Tahseen and Gonder, Eric and Tilley, Becky and Ley, David H.}, year={2007}, month={Sep}, pages={791–796} }
 @article{henry_wyatt_fletcher_2000, title={The toxicity of purified fumonisin B-1 in broiler chicks}, volume={79}, ISSN={["0032-5791"]}, DOI={10.1093/ps/79.10.1378}, abstractNote={An investigation of the toxicity of fumonisin B1 (FB1), a toxic metabolite of Fusarium moniliforme, in broiler chicks was conducted. Purified FB1 (98.1% pure) was incorporated into the diets of broiler chicks at 0, 20, 40, and 80 mg/kg, and fed to chicks from 0 to 21 d of age. Dietary FB1, at concentrations of 80 mg/kg or less, did not adversely affect body weight, feed efficiency, or water consumption of broiler chicks. The relative weights of the liver, spleen, kidney, proventriculus, and bursa of Fabricius were also unaffected (P < 0.05) by any dietary concentration of FB1 compared with the control (0 mg/kg) group. Total liver lipids of chicks fed 40 or 80 mg FB1/kg were significantly lower than those of the chicks fed either 0 or 20 mg FB1/kg of feed. Liver sphinganine concentration and the sphinganine:sphingosine ratio were increased significantly in all treated groups. Chicks fed dietary FB1 at 80 mg/kg had significantly higher serum glutamate oxaloacetate aminotransaminase:aspartate aminotransferase ratios and levels of free sphinganine in the serum. The results of this investigation agree with the results previously described, in which FB1 was supplied to diets from the use of F. moniliforme-contaminated grain; therefore, the use of such material as the source of the mycotoxin in animal feeding studies is appropriate.}, number={10}, journal={POULTRY SCIENCE}, author={Henry, MH and Wyatt, RD and Fletcher, OJ}, year={2000}, month={Oct}, pages={1378–1384} }