Totally 75 common carp and 100 big head
fishes were caught by using net from fish farms in Mashhad,
northeast of Iran. In laboratory skin, eye and fin of
fishes were inspected by stereomicroscope and in second
phase direct smears are prepared from probable lesions.
Gills were dissected and its filaments were placed in petri
dishes and fixed by Glycerin. In total 50 parasites (consist
19 protozoa and 31 metazoa) were recorded from fishes.
The parasites represented in Protozoa (Ichthyophthirius
multifiliis and Trichodina sp.) and Monogenea) Dactylogyrus
spp.) and Copepoda (Lernea cyprinacea). During this
study, infection with Dactylogyrus spp. was recorded on
fish in all months. Mean intensity of Dactylogyrus spp.
varied significantly among the seasons (P\0.05). The
maximum mean intensity was recorded in winter. Also
infection with Lernea cyprinicea in spring was significantly
higher than other seasons (P\0.05). The results of this
study together with the previously recorded prevalence of
parasitic infection in fishes support that infection to
external parasites (both protozoa and metazoa) is widespread
cause for losses in fish farms of Iran
کلید واژگان :
External parasite Cyprinus carpio Hypophthalmichthys nobilis
