الفهرس 
INTRODUCTION
Occurrence of Campylobacter jejuni in laying hens environmentsOnly 14 pages are availabe for public view
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Abstract
Campylobacter jejuni (C. jejuni) is currently one of the most important foodborne zoonotic agents worldwide with annually hundreds of thousands of human cases. To be able to establish effective control measures toward C. jejuni, the knowledge of sources and reservoirs as well as the means of transmission of this organism is of great importance. C. jejuni is most often transmitted through chicken meat to humans. High prevalences are also known for laying hens, although infections over the egg play only a minor or no role. However, C. jejuni is excreted in significant amounts in the faeces in layer houses. Also over the air transmission is possible, because contaminated feces particels are released and can be distributed as part of the airborne dust in the house and via the exhaust air in the barns environment. Laying hen holdings and their airborne, liquid and solid fecal emissions represent a reservoir for C. jejuni whose transmission potential is not yet well understood.
Research Results:
-In naturally contaminated feces C. jejuni can survive up to 6 days as demonstrated by colony cultures.
-There was a difficulty to detect culturable C. jejuni from air.
-In contrast, DNA of C. jejuni was successfully recovered from air and dust samples with subsequent isolation and identification when appropriate air sampling methods are applied.
-The prevalence and the genetic diversity of C. jejuni increased with age of birds, means that, the longer the laying period lasted, the higher the detection rate. Particular outstanding is the fact that with the increasing age of the birds during their life span, the also increased.
-The ATP content in C. jejuni cells which are in a dormant (not culturable) state not significantly differ from the ATP content of dead in C. jejuni cells.
Research Recommendations:
-These studies indicate that with the help of specific hygiene and analytical measures we can improve our knowledge so far that an effective interruption of the transmission pathways of C. jejuni appears to become possible in the near future.
-It seems necessary to develop more gentle air collection methods for C. jejuni.