Trichodinid Parasites on the Gills ofChanna punctatusfrom the Wild and Cultured Environments in Sylhet, Bangladesh

Two trichodinid parasites, Trichodina cyprinocola and Trichodina pediculus, were acknowledged in the gills during a sampling preparation of thirty fish Channa punctatus from the wild and cultured environments. However, Trichodina pediculus was recorded only in one farmed fish. From a total of 33 parasites, 26.67% were encountered in wild and 46.67% in cultured fish. The overall incidence of infection by Trichodina cyprinocola was 33.33% whilst Trichodina pediculus was only 3.33%. Records from statistical analysis as well affirmed that fish host from the cultured environment constituted the highest rate of intensity (3.43±1.4), density (1.6±2.0), and infection index (11.2±13.95) values. Both trichodinid species are identified based on the study in their unique denticles structure. Relatively large size of adhesive disc with tiny curved denticles and elongated denticle rays are the exceptional denticle morphology observed in Trichodina pediculus and compact association of sickle denticles with round tangent point alongside short vigorous upright rays evaluated the Trichodina cyprinocola