title: Infection ecology of Philometra ovata (Nematoda: Philometridae) in a wild European minnow (Phoxinus phoxinus) population in Finland.
abstract: Seasonal life cycle of body cavity dwelling (BCD) Philometra ovata (Nematoda: Philometridae) has been reported in southern and central European countries, but its swim bladder dwelling (SBD) stage and northern populations have remained unstudied. In this study, we investigated the seasonal life cycle and infection ecology of P. ovata in both swim bladder and body cavity in the European minnow (Phoxinus phoxinus) in Finland. The larval P. ovata infected the swim bladder of minnows mainly in August. Female SBD P. ovata emigrated to body cavity mostly in September, grew to their full size by the end of the next June, and evacuated from minnows in July. In addition, female SBD P. ovata retarding their development and staying in swim bladder were found commonly in minnows, thus the mean monthly prevalence (6·7 ± 3·9%) and mean intensity (1·4 ± 0·8) of BCD P. ovata was lower than that of SBD P. ovata (37·8 ± 15·1% and 2·0 ± 1·5, respectively). Finally, despite the large size of BCD individuals, infection of P. ovata did not impair body condition and relative gonad size of minnows, but increased the mortality and caused physical damages in their hosts during the evacuation period.
authors: Department of Biology,University of Eastern Finland,P.O. Box 111,FIN-80101,Joensuu,Finland.
authors: Yi-Te
authors: YT
authors: Lai
authors: Department of Biological and Environmental Science,University of Jyväskylä,Jyväskylä,Finland.
authors: Jouni
authors: J
authors: Taskinen
authors: Department of Biology,University of Eastern Finland,P.O. Box 111,FIN-80101,Joensuu,Finland.
authors: Jukka
authors: J
authors: Kekäläinen
authors: Department of Biology,University of Eastern Finland,P.O. Box 111,FIN-80101,Joensuu,Finland.
authors: Raine
authors: R
authors: Kortet
mesh_terms: D000400:Air Sacs / Q000469:parasitology*; D000818:Animals; D003530:Cyprinidae / Q000469:parasitology*; D017176:Dracunculoidea / Q000502:physiology*; D017753:Ecosystem; D005260:Female; D005387:Finland / Q000453:epidemiology; D005393:Fish Diseases / Q000453:epidemiology* / Q000469:parasitology; D007814:Larva / Q000502:physiology; D008297:Male; D015995:Prevalence; D012621:Seasons; D017205:Spirurida Infections / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*
keywords: European minnow; Philometra ovata; Phoxinus phoxinus; body cavity; intensity; parasitic infection; prevalence; swim bladder