MLBA12:  December / January 2010

 

 

 

 

Infectious bronchitis virus (IBV) is the prototype species of the family Coronaviridae in the order Nidovirales. More than 25 genotypes are distributed worldwide. IBV caus­es an acute highly-contagious viral respiratory disease of chickens which is characterised by respiratory rales, coughing and sneezing.

 

Some IBV strains replicate in the gastrointestinal tract, oviduct and kidney, and due to their nephropatho­genic properties, they have the poten­tial to cause severe losses with up to 44 percent mortality. In other cases, infection of the proventriculus leads to 75-100 percent mortality in young birds. Most isolates of IBV replicate well in the developing chicken em­bryo following inoculation of the al­lantoic cavity, and high titers of vi­rus can be isolated from the allantoic fluid.

 

Replication of IBV strains M41 and Beaudette in vitro is restricted to primary chicken cells and depends on the expression of 2,3-linked sialic acids on the cell surface. Thus, these molecules are supposed to serve as receptor determinants for primary at­tachment of IBV to host cells.

 

The aim of this study was first to evaluate the suitability of immuno­histochemistry (IHC) for detection of IBV antigen in paraffinwax embed­ded CAM and second to analyse the viral antigen distribution in different embryonic tissues between 48 hours and 120 hours after experimental in­fection.