Author:
SIDDALL R.,KOSKIVAARA M.,VALTONEN E. T.
Abstract
Experimental exposure to bleached kraft pulp and paper mill effluent
(BKME) at a concentration of 10% significantly
reduced the abundance and mean number of species of Dactylogyrus
on
the gills of naturally infected roach, Rutilus rutilus,
over a 3 week period. Seven Dactylogyrus species were recorded
which
differed widely in their susceptibility to the effluent.
The experiment coincided with a natural spring peak in dactylogyrid infections
on roach. BMKE exposure did not prevent
parasite reproduction but post-larval abundance was significantly higher
on
control than effluent-exposed hosts. There
was no evidence of a BKME-induced shift in microhabitat distribution of
dactylogyrids. Elevated levels of infection with
Dactylogyrus spp. have been recorded on roach from a Finnish lake
containing relatively low concentrations of BMKE.
The high exposure concentration in this experiment produced a similar reduction
in dactylogyrid infections to that
reported in separate studies in close proximity to Swedish pulp and paper
mills. The discrepancy between the results of
the Finnish and Swedish field investigations is therefore considered to
be
due to differences in BKME concentration between the study areas.
Publisher
Cambridge University Press (CUP)
Subject
Infectious Diseases,Animal Science and Zoology,Parasitology