As grass carp culture for vegetation control in freshwater is a new field in Turkey the disease problems of grass carp have not been well documented. Spontaneous disease occurrence in the course of grass carp culture was reported in the present study. During the culture of grass carp (Ctenopharyngodon idella) some disease problems occurred causing a high level of mortality. In two-month old fry (5.55±0.19 g) fed with alfa-alfa in out-door conditions bacterial disease and some ectoparasites on the gills and skin were detected. The bacterium was identified as Aeromonas hydrophila and the ectoparasites as Trichodina sp., Dactylogyrus sp. and Chilodonella sp. The mortality rate reached 70% in these two-month old fry. After this outbreak the remaining healthy population was transferred to in-door conditions for better controlled conditions. Following transportation to in-door conditions an ectoparasite identified as Ichthyophthirius multifiliis caused a high mortality rate of 80%. Additionally, one-year-old grass carp (52.67±0.88 g) fed with supplemental commercial carp feed in earthen ponds were examined for endoparasites. The cestods, Ligula intestinalis and Bothriocephalus gowkongensis existed in the abdominal cavity; dominantly B. gowkongensis. In one-year-old grass carp the mortality rate was low, although growth was impaired.

As grass carp culture for vegetation control in freshwater is a new field in Turkey the disease problems of grass carp have not been well documented. Spontaneous disease occurrence in the course of grass carp culture was reported in the present study. During the culture of grass carp (Ctenopharyngodon idella) some disease problems occurred causing a high level of mortality. In two-month old fry (5.55±0.19 g) fed with alfa-alfa in out-door conditions bacterial disease and some ectoparasites on the gills and skin were detected. The bacterium was identified as Aeromonas hydrophila and the ectoparasites as Trichodina sp., Dactylogyrus sp. and Chilodonella sp. The mortality rate reached 70% in these two-month old fry. After this outbreak the remaining healthy population was transferred to in-door conditions for better controlled conditions. Following transportation to in-door conditions an ectoparasite identified as Ichthyophthirius multifiliis caused a high mortality rate of 80%. Additionally, one-year-old grass carp (52.67±0.88 g) fed with supplemental commercial carp feed in earthen ponds were examined for endoparasites. The cestods, Ligula intestinalis and Bothriocephalus gowkongensis existed in the abdominal cavity; dominantly B. gowkongensis. In one-year-old grass carp the mortality rate was low, although growth was impaired.