Detection and isolation of infectious laryngotracheitis virus on a broiler farm after a disease outbreak.

A broiler farm in North Alabama suffered a mild infectious laryngotracheitis (ILT) outbreak, as determined by clinical disease and PCR. The poultry integrator sought help to control further outbreaks in subsequent flocks. Samples were collected from various areas of the poultry houses on the farm over an 8-wk period.

Infectious laryngotracheitis virus in chickens.

Infectious laryngotracheitis (ILT) is an important respiratory disease of chickens and annually causes significant economic losses in the poultry industry world-wide. ILT virus (ILTV) belongs to alphaherpesvirinae and the Gallid herpesvirus 1 species. The transmission of ILTV is via respiratory and ocular routes.

Detection and differentiation of avian reoviruses using SYBR-Green I-based two-step real-time reverse transcription PCR with melting curve analysis.

A two-step SYBR-Green I-based real-time PCR with melting curve analysis was developed to detect and differentiate the avian reovirus (ARV) sigmaC gene in field and vaccine ARVs. Three primer sets were used to amplify the sigmaC gene from its 5', center, and 3' regions and analyze the melting point temperatures of nine ARVs. By combining the melting curves of the three ARV sigmaC gene regions, melting curve analysis could accurately distinguish the ARVs of different subtypes, and the results were consistent with phylogenetic analysis.

Subtyping animal influenza virus with general multiplex RT-PCR and Liquichip high throughput (GMPLex).

This study developed a multiplex RT-PCR integrated with luminex technology to rapidly subtype simultaneously multiple influenza viruses. Primers and probes were designed to amplify NS and M genes of influenza A viruses HA gene of H1, H3, H5, H7, H9 subtypes, and NA gene of the N1 and N2 subtypes. Universal super primers were introduced to establish a multiplex RT-PCR (GM RT-PCR).

Comparison of a TaqMan real-time polymerase chain reaction assay with a loop-mediated isothermal amplification assay for detection of Gallid herpesvirus 1.

A TaqMan real-time polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) assay were developed to detect Gallid herpesvirus 1 (GaHV-1, formerly Infectious laryngotracheitis virus). The standard curve of real-time PCR was established, and the sensitivity reached 10 copies/μl. In the current study, the conversion between viral titer and GaHV-1 genomic copy number was constructed.

Development of TaqMan real-time RT-PCR for detection of avian reoviruses.

Avian reoviruses (ARVs) are an important cause of economic losses in commercial poultry. A TaqMan real-time RT-PCR assay for detecting of ARVs was developed. The primer-probe set was from the conserved region of ARV S4 genome segment.

Toward the development of a plant-based vaccine against reovirus.

Transgenic lines of Arabidopsis thaliana producing recombinant TC protein were developed. The S1 gene encoding sigmaC protein of an avian reovirus (ARV) was amplified by reverse-transcription PCR (RT-PCR). The amplified product was cloned into a plant-expression vector, pE1857, with a strong promoter for expression.

Integrity of a recombinant hemagglutinin protein of an avian influenza virus.

An open reading frame representing cDNA from a hemagglutinin (HA) encoding gene of a low pathogenic avian influenza virus (AIV) subtype H10N7 was cloned in the pNMT1-TOPO vector under the control of thiamine response promoter. This construct was designated as pNMT1-HA. The pNMT1-HA construct was transformed into Schizosaccharomyces pombe for expression of HA antigen.

Immunization of chickens with VP2 protein of infectious bursal disease virus expressed in Arabidopsis thaliana.

Transgenic plants represent a safe, effective, and inexpensive way to produce vaccines. The immunogenicity of VP2 protein of an infectious bursal disease (IBD) virus variant E isolate expressed in transgenic Arabidopsis thaliana was compared with a commercial vaccine in specific-pathogen-free broiler chickens. The VP2 coding sequence was isolated and integrated into A.

Immunosuppression in specific-pathogen-free broilers administered infectious bursal disease virus vaccines by in ovo route.

The effect of two infectious bursal disease virus (IBDV) vaccines (IBDV-immune complex [Icx] and IBDV-2512), administered in ovo, on the cell-mediated immunity of specific-pathogen-free (SPF) broilers was examined. A decrease (P < 0.05) in the T-cell mitogenic response occurred in birds vaccinated with both vaccines on days 9 and 21 post in ovo vaccination (PIOV), but an increase (P < 0.

Evaluation of the immune response and detection of infectious bursal disease viruses by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay after in ovo vaccination of commercial broilers.

Maternal immunity can interfere with infectious bursal disease virus (IBDV) vaccine efficacy. The effect of maternal antibody (MacAb) on the immune response and detection of two vaccine viruses, an IBDV immune complex (cx) and IBDV-2512, was investigated. Vaccines were administered in ovo at 100 mean embryo infectious dose to commerical broiler embryos derived from young (29 wk) or old (63 wk) flocks.

Comparison of cell culture systems for duck hepatitis B virus using SyBr green quantitative PCR.

The Hepadnaviridae family contains DNA viruses such as human hepatitis B virus (HBV), woodchuck hepatitis B virus (WHV), and duck hepatitis B virus (DHBV). DHBV is distributed in both wild and domestic ducks. HBV is a worldwide health problem with carriers at risk of developing cirrhosis and liver cancer.

Development of viral disinfectant assays for duck hepatitis B virus using cell culture/PCR.

Human hepatitis B virus (HBV) is a worldwide public health problem with chronic carriers at risk for developing cirrhosis and hepatocellular carcinoma. Accidental nosocomial infections from inadequately disinfected equipment or exposure to blood and body fluids from patients are major routes. To solve such problems, disinfectants to inactivate HBV must be validated.

Detection of duck hepatitis B virus DNA on filter paper by PCR and SYBR green dye-based quantitative PCR.

Duck hepatitis B virus (DHBV) belongs to the Hepadnaviridae family, which includes human Hepatitis B virus (HBV) and Woodchuck hepatitis virus. It is widely distributed in wild and domestic ducks due to congenital transmission. HBV is a worldwide health problem, with carriers at risk of developing cirrhosis and liver cancer.