ABSTRACT: The effect of low water temperatures on the development and viability of larval and adult Anguillicola crassus (Nematoda) in the final host Anguilla anguilla was studied. European eels were experimentally infected with A. crassus and then maintained for 4 mo at 4, 9, 10 and 19°C. Larval development showed a temperature-dependent pattern and was significantly retarded at low temperatures. Third-stage larvae survived a 4 mo period at 4°C without being affected, although they were not able to invade the swimbladder wall at this temperature. In contrast, adult worms were severely harmed during a 4 mo period at 4°C, as reflected by increased mortality and decreased growth and reproductivity compared to the worms maintained for the same period at 18°C. Starvation of the eels for 4 mo at 19°C did not affect the development and growth of the nematode. The experimentally obtained results support the hypothesis that the spread of A. crassus in boreal regions, e.g. Northern Europe, is restricted by the natural ambient temperature regimes.

KEY WORDS: Eel · Anguillicola crassus · Development · Temperature · Starvation

Published in DAO Vol. 33, No. 2 (1998) on June 19
ISSN: 0177-5103. Copyright © Inter-Research, Oldendorf/Luhe, 1998