Characterization of immune responses and immunopathology in turkeys experimentally infected with clostridial dermatitis-producing strains of Clostridium septicum.

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.

Mucosal and systemic lymphoid immune responses against strains with variable virulence in the production of necrotic enteritis in broiler chickens.

Necrotic enteritis (NE), caused by , is an economically important disease of chickens. Although NE pathogenesis is moderately well studied, the host immune responses against 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 +  strains (CP1, CP5, CP18, and CP26), of which CP18 and CP26 strains also carried the gene.

Clinicopathologic, Gross Necropsy, and Histopathologic Effects of High-Dose, Repeated Meloxicam Administration in Rhode Island Red Chickens ().

Meloxicam is a commonly prescribed non-steroidal anti-inflammatory drug for backyard poultry that has demonstrated pharmacodynamic efficacy at a single high dose of 5 mg/ kg. This study characterized the adverse effects of meloxicam administered in chickens at an approximate dose of 5 mg/kg orally twice daily for 5 days. Twenty-one adult Rhode Island Red hens (), judged to be healthy based on an external physical examination, complete blood count (CBC), and plasma biochemistry panel, were recruited for this study.

Evaluation of factors influencing the development of late Marek's disease virus-induced immunosuppression: virus pathotype and host sex.

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.

Early infection with Marek's disease virus can jeopardize protection conferred by laryngotracheitis vaccines: a method to study MDV-induced immunosuppression.

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.

History of the Journal of Veterinary Medical Education.

The Journal of Veterinary Medical Education (JVME), with the leadership of seven editors and two interim editors, grew from 33 pages of mostly news and commentary to become the premier source for information exchange in veterinary medical education. The first national publication of the Association of American Veterinary Medical Colleges (AAVMC) was a 21-page newsletter published in December 1973. This one-time newsletter was followed by volume 1, issue 1 of JVME, published in spring 1974 and edited by William W.

Instruction and Curriculum in Veterinary Medical Education: A 50-Year Perspective.

Our knowledge of veterinary medicine has expanded greatly over the past 50 years. To keep pace with these changes and produce competent professionals ready to meet evolving societal needs, instruction within veterinary medical curricula has undergone a parallel evolution. The curriculum of 1966 has given way, shifting away from lecture-laboratory model with few visual aids to a program of active learning, significant increases in case- or problem-based activities, and applications of technology, including computers, that were unimaginable 50 years ago.

Dietary toxicity of soluble and insoluble molybdenum to northern bobwhite quail (Colinus virginianus).

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.

Epithelial cell tumors of the hen reproductive tract.

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.

Transmissible viral proventriculitis identified in broiler breeder and layer hens.

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.

Cost effective and time efficient measurement of CD4, CD8, major histocompatibility complex Class II, and macrophage antigen expression in the lungs of chickens.

Cells expressing CD4, CD8, major histocompatibility complex (MHC) Class II, and macrophage biomarkers in lungs of chickens were quantified by measuring total area of antigen expressed using imageJ, a software program developed at the National Institutes of Health and available at no cost. The procedures reported here were rapid, and reproducible. Total area of antigen expressed had positive correlation with manual counts of cells expressing CD4 and CD8 biomarkers after inoculation with serotype 1 Marek's disease virus (MDV) vaccines.

Selected blood chemistry values in mobility-impaired broiler breeder hens with suspected calcium tetany using the i-STAT handheld clinical analyzer.

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.

Macrorhabdus ornithogaster (Megabacterium) infection in adult hobby chickens in North America.

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.

Identification of Ascaridia numidae in guinea fowl (Numida meleagris) and association with elevated mortality.

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.

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.

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.

Measuring the intra-individual variability of the plasma proteome in the chicken model of spontaneous ovarian adenocarcinoma.

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.

Mycoplasma iowae associated with chondrodystrophy in commercial turkeys.

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.

Pneumonia of turkey breeder hens associated with Mycoplasma synoviae.

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.