OCCURRENCE AND ABUNDANCE OF PARASITES ON CHANNA PUNCTATUS OF RAJSHAHI
The study was conducted to collect and identify the ectoparasites and endoparasites of Channa punctatus (Bloch, 1793) from different water bodies of Rajshahi district during June 2011 to April 2012. Samples were collected from different fish markets and in some cases directly from fishermen of Rajshahi city. A total of 373 fishes were examined during the study period of which 251 fishes (67.29%) were infected. Organ wise distribution, monthly, seasonally, sex and length groups wise fluctuation of prevalence, abundance and mean intensity of parasites were studied. A total of 8 different parasitic genera were collected from the host fishes. Among them 5 were ectoparasites and 3 were endoparasites. Of these five ectoparasites one was protozoan Trichodina pediculatus, and two monogenic parasites Dactylogyrus vastator and Gyrodactylus elegans, one annelid was Hirudu medicenalis and one crustacean Argulus foliaceus. Three endoparasites were Ascaridia sp. nematodes one trematodes Genarchopsis sp and acanthocephalan pallisentis sp. Highest parasitic infestations were found in intestine, second highest was found in gill and the lowest was found in skin and stomach. Parasitic infestation fluctuated from months to months. Highest parasitic infestation was found in November and the lowest in June. The host fishes showed highest prevalence value and highest abundance value in autumn season. The host fishes showed their lowest prevalence and abundance value in winter season. Parasitic infestation was found to vary with size groups and sex groups. It was noted that the hosts of intermediate length and weight groups were found to be more infected than smaller and larger length group. Females were more infested than the males.