Genetic identification of the crayfish plague (Aphanomyces astaci)

The crayfish plague disease agent Aphanomyces astaci is the most significant reason for the decline in European freshwater crayfish species. We use an agent-specific real-time PCR analysis to detect the pathogen in wild populations. Different genetic lineages of A. astaci from different American crayfish host species have shown to differ in virulence and thus pose potential danger for European crayfish species. Today at least five different genetic lineages have been confirmed to occur in Europe. As these different lineages are usually host species specific, an A. astaci lineage determination can give information on the infection pathway of indigenous European crayfish population in a natural water body.  In this context, several projects are currently under investigation:

  • As an important case study, we investigate the spread of the crayfish plague in the Romanian Danube catchment. Populations of spiny cheek crayfish (Orconectes limosus) and narrow-clawed crayfish (Astacus leptodactylus), which occur in close proximity to each another, are tested for their carrier status and also for the genetic lineage of A. astaci. Our aim is to gather information about how and through which crayfish host species the crayfish plague agent was introduced into the Danube delta. (Partner: West University of Timisoara, Romania)
  • Another part of the project focuses on the spread of the crayfish plague agent in Germany and Austria. We tested numerous populations of crayfish in both countries for an infection with the crayfish plague and are working on the identification of the A. astaci lineages. The distribution patterns of the different A. astaci lineages are of high importance for conservation efforts within Germany and Austria.
  • We also plan the identification of A. astaci lineages from crayfish, which were collected in North America. We are interested in the infection status of different species in their native environment and the distribution of the lineages.

 

narrow-clawed crayfish

Astacus leptodactylus (narrow-clawed crayfish) with melanised spots (Photo: Parvulescu).

 

 

spiny cheek crayfish

Infected spiny cheek crayfish (Orconectes limosus) (Photo: Parvulescu)

 

 

Contact

Anne Schrimpf

Jörn Panteleit