Infestation of Nematode Parasite Filochona Teleostei in Relation to Size, Weight and Age of Snow Trout Schizothorax Richardsonii (Gray)

Abstract

Parasitological investigation was conducted to assess the effects of various biotic factors viz. length, weight and age of host on the infection patterns of Filochona teleostei (Singh & Malik, 1992) in snow trout Schizothorax richardsonii (HAM.) from hill streams of Garhwal Himalayas. The statistical analysis was carried out to calculate infection incidence, mean worm burden, regression values and their significance. About 20% fishes (18% male and 22% female) were found infected with nematode parasites. Infection patterns of Filochona teleostei revealed a negative correlation (r= - 0.347 to - 0.734) with length, (r= - 0.499 to - 0.671) with weight and (r= - 0.576) with age of host fish. The age immunity and stronger host resistance developed by the larger fishes are the possible reasons for the decrease in infection in larger and older fishes.