Abstract

Dutch wild eels [Anguilla anguilla (L.)] and smelt [ Osmerus eperlanus (L.)] from freshwater and saltwater areas in the Netherlands were collected from 1986 to 1992 and their swimbladders were examined for Anguil/icola crassu.o; (Nematoda, Dracunculoidea) and for parasite-related pathological changes. Throughout the 6-year sampling period, young eels (up to 17 cm) showed severe pathological changes due to the parasite. The prevalence of Infection in larger eels (23-34 cm) showed the highest prevalence between 1987 and 1988, and the highest intensity (i.e. number of parasites per infected fish) between 1988-1989. After 1989 the prevalence of the parasite decreased, and the lesions became less severe. Larger eels (23-34 cm) from the Waddenzee (salt water), which is close to the !Jsselmeer, showed a high prevalence of the parasite from 1987 to 1990, although the intensity of infection decreased from 1987 onwards, as did the percentage of fibrotic swimbladders after 1988. Smel~ which is a paratenic host for larvae of A. crassu.o; and which is a prey for large eels, showed a sharp decrease In prevalence of the parasite shortly after 1988. Thereafter the prevalence stayed rather constant at about 40% of the smelt population. No pathological changes were found in the smelt.

Published in

Aquaculture
1994, Volume: 126, number: 3-4, pages: 219-229

UKÄ Subject classification

Fish and Aquacultural Science


Publication identifier

DOI: https://doi.org/10.1016/0044-8486(94)90038-8

Permanent link to this page (URI)

https://res.slu.se/id/publ/40572