DISTRIBUTION PATTERNS OF A NEMATODE PARASITE INFESTING GARHWAL MAHSEER TOR TOR (HAM.).

Parasitological investigations were conducted on hill-stream fish Tor tor (HAM.) to describe the distribution patterns of nematode parasite Rhabdochona (Rhabdochona) nemachili (Rautela and Malhotra, 1982). Study showed that the parasite was more overdispersed in March 2015 and January 2016 followed by November in both the years while in other months the degree of overdispersion was low. Frequency distribution of Rhabdochona (Rhabdochona) nemachili in Tor tor was tested on Poisson series and for goodness of fit to the negative binomial distribution. Agreement with Poisson series was good (p < 0.001). Fishes with zero infection dominated the sample in greater number of months during infection periods. The values of variance to mean ratio suggested that the Negative Binomial Distribution would be a great model for the distribution of this parasite. Agreement between the original distribution and the negative binomial, as tested by X2 (Goodness of fit) was good. [ABSTRACT FROM AUTHOR]