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The pathogenic helminth parasites of eels
1School of Biological Sciences, University of Exeter, Exeter, UK. c.r.kennedy@exeter.ac.uk
Journal of Fish Diseases
|May 15, 2007
Summary
The nematode Anguillicola crassus and monogeneans Pseudodactylogyrus spp. are serious eel pathogens, particularly in aquaculture. While controllable with drugs in culture, their impact in the wild, especially on eel migration, remains a concern.
Area of Science:
- Aquatic Parasitology
- Eel Aquaculture
- Fish Pathology
Background:
- Eels host numerous helminth species, but few are considered serious pathogens.
- Pseudodactylogyrus spp. (monogeneans) and Anguillicola crassus (nematode) are significant pathogens affecting eels.
Purpose of the Study:
- To identify and describe the pathogenic potential of specific helminth species in Atlantic and Pacific eels.
- To analyze the factors contributing to the pathogenicity of Pseudodactylogyrus spp. and Anguillicola crassus in different environments.
Main Methods:
- Review of existing literature on helminth infections in eels.
- Analysis of parasite life cycles, host-parasite interactions, and environmental influences on pathogenicity.
- Evaluation of control strategies in aquaculture versus wild populations.
Main Results:
- Pseudodactylogyrus spp. cause severe gill damage in high densities, manageable with drugs in aquaculture.
- Anguillicola crassus exhibits high adaptability, causing swimbladder damage, reduced hydrostatic function, and increased stress in eels.
- A. crassus pathogenicity is pronounced in introduced environments (Europe, Far East) and potentially impacts eel migration and population dynamics.
Conclusions:
- Pseudodactylogyrus spp. and Anguillicola crassus pose significant threats to eel health, especially in aquaculture and introduced ecosystems.
- Environmental factors and parasite adaptability influence disease severity and spread.
- Effective control is feasible in aquaculture but challenging in wild eel populations, necessitating further research into their ecological impact.
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