Infestation of Rastrelliger kanagurta, with Cymothoid Isopod, Joryma brachysoma in the Colachel Environment of Southwest Coast of India

Abstract: The parasitic infestation of isopod parasites in the commercially important fish Rastrelliger kanagurta was investigated. The study was carried out to establish the extent of parasitisation of fish species and quantify the relationship between the parasites and their fish hosts. The prevalence and intensity of infestation in R. kanagurta during different months from Feb-2007 to jan-2008. It was maximum in January (49.1) and minimum in July (7.5). In males the prevalence was maximum in January (38.1) and minimum in August (8.3). The intensity ranged from 0.3 in May and 1.8 in February. In females the prevalence was maximum in January (56.2) and minimum in October (10.5). The maximum intensity (2.2) was recorded in June and minimum (1) was recorded in July and October. Key words: Infestation % Isopod % Parasite % Rastrelliger kanagurta % Prevalence INTRODUCTION on marine fish parasitology [14] with most of the work Marine fish parasitology is a rapidly developing field Isopods absorb their nourishment directly from the of aquatic science. This is due to the growing importance host’s body depend upon their host’s for feeding. of marine aquaculture, concerns on pollution effects on Studies Pertaining to pathological effects of isopod fish health and a generally increasing interest in parasites on the physiology of host fish are scantly an