Reproducibility of swollen sinuses in broilers by experimental infection with avian metapneumovirus subtypes A and B of turkey origin and their comparative pathogenesis.

Clinic for Poultry, University of Veterinary Medicine, Hannover, Germany.
Avian Pathology (Impact Factor: 1.73). 03/2008; 37(1):65-74. DOI: 10.1080/03079450701802222
Source: PubMed

ABSTRACT Swollen head syndrome (SHS) associated with avian metapneumovirus (aMPV) subtype A or subtype B in broilers and broiler breeders has been reported worldwide. Data about pathogenesis of aMPV subtypes A and B in broilers are scarce. It has been difficult to reproduce swollen sinuses in chickens with aMPV under experimental conditions. In the field, SHS in broilers is suspected to be induced by combined infections with different respiratory pathogens. The objectives of the present study were to compare the pathogenesis of subtypes A and B aMPV in commercial broilers and to investigate the reproducibility of clinical disease. In two repeat experiments, commercial broilers free of aMPV maternal antibodies were inoculated with aMPV subtypes A and B of turkey origin. The clinical signs such as depression, coughing, nasal exudates, and frothy eyes appeared at 4 days post inoculation, followed by swelling of periorbital sinuses at 5 days post inoculation. Higher numbers of broilers showed clinical signs in subtype-B-inoculated compared with subtype-A-inoculated groups. Seroconversion to aMPV was detectable from 10 to 11 days post inoculation. The appearance of serum aMPV enzyme-linked immunosorbent assay antibodies and the clearance of the aMPV genome coincided. Subtype B aMPV showed a broader tissue distribution and longer persistence than subtype A. Histopathological changes were observed in the respiratory tract tissues of aMPV-inoculated broilers, and also in paraocular glands, such as the Harderian and lachrymal glands. Overall, our study shows that representative strains of both aMPV turkey isolates induced lesions in the respiratory tract, accompanied by swelling of infraorbital sinuses, indicating the role of aMPV as a primary pathogen for broilers.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Avian metapneumovirus (AMPV) is an emerging pathogen causing respiratory and reproductive illness in poultry worldwide. To demonstrate the presence of AMPV in domestic chickens in Korea, we attempted to isolate AMPV from affected chickens. A cytopathic agent was isolated using chicken tracheal ring culture from dead chickens from a broiler breeder farm with reduced egg production in Korea. This agent, termed SC1509 strain, subsequently passed in Vero cells with distinct cytopathic effects. The SC1509 strain was confirmed as avian metapneumovirus (AMPV) using both RT-PCR test and monoclonal antibody-based immunofluorescence assay. Sequence analysis based on the G glycoprotein revealed that the SC1509 strain had 22.5 to 96.0% nucleotide sequence identity and 11.1 to 92.7% predicted amino acid sequence identity with previously published AMPV strains, particularly with the highest sequence homology (95.8 to 96% for nucleotides and 92.2 to 92.7% for amino acids) to European strains belonging to genotype B. The SC1509 strain was phylogenetically clustered with genotype B viruses, confirming that the SC1509 strain belongs to genotype B. This is the first report of genotype B avian metapneumovirus from chickens in Korea. 감염증은 닭과 칠면조에서 호흡기 증상, 두부종창증 (swollen head syndrome), 산란저하 및 탈색란, 연각란 등 비정상란 발생 등을 유발하는 호흡기성 바이러스성 전염 병이다 (1). 이 전염병은 과거에 칠면조 비기관염 (turkey rhinotracheitis), 조류비기관염 (avian rhinotracheitis), 두부 종창증, 조류뉴모바이러스 감염증 (avian pneumovirus infection) 등으로 불리어 졌다 (1). 최근에 동물보건기구 (OIE)는 이 질병을 AMPV 감염증 또는 칠면조 비기관염 으로 공식 명명하고 있다 (2). 이 질병의 병원체인 AMPV는 2001년 사람에서 최초로 분리 보고된 사람 메타뉴모바이러스 (human metapneumo-virus) (3)와 함께 파라믹소비리데 과 (Family Paramyxo-viridae)의 새로운 genus인 Genus Metapneumovirus에 속하 는 바이러스로 분류되었다 (4). AMPV는 3'-N(nucleocapsid) -P(phosphoprotein)-M(matrix)-F(fusion)-M2(second matrix)-SH(small hydrophobic)-G(attachment glycoprotein)-L(large polymerase)-5'의 순서대로 8개의 유전자 배열로 구성된 single-stranded, negative sense RNA genome을 가지고 있다 (5). AMPV는 G 단백질의 염기서열 분석결과를 바탕으로 A에서 D까지 4개의 genotype이 있다 (6, 7). Genotype A와 B는 아시아 (8~11), 유럽 (6, 12, 13), 아프리카 (11, 14)의 칠면조와 닭에서 주로 보고되고 있으며, genotype C는 미 국과 캐나다지역의 칠면조와 야생조류에서 주로 분리 보 고 (15~17)되고 있으며, 그리고 genotype D는 프랑스의 오리에서 (18) 분리 보고된 바 있다.
    Journal of Bacteriology and Virology 01/2009; 39:373-382.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The feasibility of using Flinders Technology Associates (FTA) cards for the molecular detection of avian metapneumovirus (aMPV) by reverse transcriptase-polymerase chain reaction (RT-PCR) was investigated. Findings showed that no virus isolation was possible from aMPV-inoculated FTA cards, confirming viral inactivation upon contact with the cards. The detection limits of aMPV from the FTA card and tracheal organ culture medium were 10(1.5) CD50/ml and 10(0.75) CD50/ml respectively. It was possible to perform molecular characterization of both subtypes A and B aMPV using inoculated FTA cards stored for up to 60 days at 4-6°C. Tissues of turbinate, trachea and lung of aMPV-infected chicks sampled either by direct impression smears or by inoculation of the tissue homogenate supernatants onto the FTA cards were positive by RT-PCR. However, the latter yielded more detections. FTA cards are suitable for collecting and transporting aMPV-positive samples, providing a reliable and hazard-free source of RNA for molecular characterization.
    Avian Pathology 01/2014; · 1.73 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We investigated the properties of the spin-1/2 ferromagnetic–antiferromagnetic–antiferromagnetic alternating Heisenberg chain using the spin-wave theory. The spin-wave excitation spectra, the sublattice magnetizations and the local bond energies of the model are calculated to be compared with the corresponding properties of the mixed spin (1, 1/2) chain for a range of α. The results demonstrate that all the properties show similar behaviours in the small α limit, so the properties of the mixed spin (1, 1/2) chain can be described using the spin-1/2 ferromagnetic–antiferromagnetic–antiferromagnetic alternating Heisenberg chain.Research Highlights►The spin-wave excitation spectra, the sublattice magnetizations and the local bond energies of the spin-1/2 ferromagnetic–antiferromagnetic–antiferromagnetic alternating Heisenberg chain are calculated. ►In the small α limit, the properties of the mixed spin (1,1/2) chain can be described using the spin-1/2 ferromagnetic–antiferromagnetic–antiferromagnetic alternating Heisenberg chain. ►The spin-1/2 ferromagnetic–antiferromagnetic–antiferromagnetic alternating Heisenberg chain may be of interest for some real quasi-one-dimensional molecular magnetic materials.
    Physica B Condensed Matter 01/2011; 406(4):781-784. · 1.28 Impact Factor

Full-text (2 Sources)

1 Download
Available from