Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Epidemiologic Studies on Infectious Coryza Outbreaks in Northern New South Wales, Australia, Using Serotyping, Biotyping, and Chromosomal DNA Restriction Endonuclease Analysis

P. J. Blackall, C. J. Morrow, A. McInnes, L. E. Eaves and D. G. Rogers
Avian Diseases
Vol. 34, No. 2 (Apr. - Jun., 1990), pp. 267-276
DOI: 10.2307/1591408
Stable URL: http://www.jstor.org/stable/1591408
Page Count: 10
  • Read Online (Free)
  • Download ($12.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Epidemiologic Studies on Infectious Coryza Outbreaks in Northern New South Wales, Australia, Using Serotyping, Biotyping, and Chromosomal DNA Restriction Endonuclease Analysis
Preview not available

Abstract

The epidemiology of 16 cases of infectious coryza, an upper respiratory tract disease of chickens caused by Haemophilus paragallinarum, was investigated in a retrospective study. The cases occurred over a 14-month period on 10 farms in northern New South Wales. The available field data indicated that the cases formed six unrelated outbreaks. The 16 isolates of H. paragallinarum were subjected to serotyping by the Page and Kume schemes and biotyping based on carbohydrate fermentation and antimicrobial drug-resistance patterns. As well, newer fingerprinting techniques-plasmid profiles, whole-cell protein profiles, immunoblots of whole-cell protein profiles and total DNA restriction endonuclease analysis (REA)-were evaluated. Antimicrobial biotyping and REA profile typing proved most useful, allowing the recognition of three groups among the isolates. The other techniques gave either limited or no subdivision among the isolates. The combined results of the laboratory study indicated that, rather than six unrelated outbreaks, the 16 isolates represented three pairs of related outbreaks. This study represents the first application of sensitive biotyping and fingerprinting techniques to outbreaks of infectious coryza. The results have established that farms can be repeatedly infected with a single strain of H. paragallinarum that re-emerges at intervals. This study also obtained the first detailed evidence that replacement stock are a major source of infectious coryza. /// En un estudio retrospectivo, se investigó la epidemiología de 16 casos de corinza infecciosa, una enfermedad del tracto respiratorio superior de los pollos causada por Haemophilus paragallinarum. Los casos ocurrieron en un periodo de 14 meses en 10 granjas en New South Wales, Australia. Los datos de campo indicaron que los casos pertenecieron a 6 brotes separados. Las 16 cepas de H. paragallinarum fueron serotipificadas siguiendo los procedimientos de Page y Kume, y biotipificadas basados en la fermentación de carbohidratos y los patrones de resistencia a drogas antimicrobianas. Así mismo, se usaron técnicas más modernas de análisis de huella de oligonucleótidos, perfiles de plásmidos y de proteínas, inmunotransferencias de los perfiles de las proteínas de la bacteria y análisis total del ADN con endonucleasas de restricción. La biotipificación antimicrobiana y el perfil con las endonucleasas de restricción fueron los más útiles, permitiendo reconocer tres grupos entre las cepas aisladas. Las otras técnicas no permitieron separas las cepas aisladas o tuvieron limitaciones. Los resultados combinados del estudio de laboratorio indicaron que en vez de seis brotes separados, las 16 cepas aisladas representaron tres pares de brotes relacionados. Este estudio representa la primera aplicación de los análisis de huella de los oligonucleótidos y biotipificación de los brotes de coriza. Los resultados han establecido que las granjas pueden tener una infección crónica causada por una sóla cepa de H. paragallinarum que reaparece a intervalos. Este estudio también muestra la primera evidencia detallada indicando que las aves de reemplazo son la mayor fuente de coriza infecciosa.

Page Thumbnails

  • Thumbnail: Page 
267
    267
  • Thumbnail: Page 
268
    268
  • Thumbnail: Page 
269
    269
  • Thumbnail: Page 
270
    270
  • Thumbnail: Page 
271
    271
  • Thumbnail: Page 
272
    272
  • Thumbnail: Page 
273
    273
  • Thumbnail: Page 
274
    274
  • Thumbnail: Page 
275
    275
  • Thumbnail: Page 
276
    276