A survey of monogenea and digenea trematodes prevalence in warm water cultivated Cyprinidae in Kerman province

Growth loss, immune system suppression and sometimes high mortality are side effects of many parasitic diseases that cause a lot of damages to fish farmers. In high condensation of warm water cultivated fish, Monogenea and digenea trematodes can be regarded as a serious threat. The aim of this study was to investigate the infestation of cultivated cyprinidae fish with monogenea and digenea trematodes in different seasons in Kerman province.This survey was done on four species of warm water fish (common carp, silver carp, grass carp and bighead carp) with the mean weight (Standard deviation) 435±46 gram and age 11 weeks in fish cultivation farms of Kerman province in four seasons in 2009. After harvesting and anesthetizing, a wet slide was prepared from skin, gills and fish lenses and it was studied by a light microscope. For data analysis, the epidemiologic index of ratio of alea and chi-square test with stata 10 statistical software and 0.05 significant levels was used.Of a total of 910 harvested fish, 361 fish (39.7%; confidence interval 95%: 36.5- 42.8%) were infested with dactylogyrus, gyrodactylus and diplostomummetacercariae. The highest rate of infestation was observed with dactylogyrus, diplostomummetacercariaeand gyrodactylus, respectively (52.4%, 38.5% and 9.1%). The highest rate of infestation with dactylogyrus and gyrodactylus was seen in grass carps (26.76% and 7.75%, respectively), but the highest rate of infestation with diplostomum Metacercariae was observed in silver carps (21.10%).The comparison of different seasons showed the highest and lowest rate of infestation were in fall and spring (52.8% and 13.74%), respectively. The high level of infestation in fallandwinteris due toimmigrationof kingfisherbirdsto theregion in these seasons. In comparison with spring, the proportion of infestation in other seasons was achieved statistically significant. Note that, no infestation was seen with diplostomummetacercariae in spring