Occurrence of a nematode Philometra(Costa,1845)in the ovaries of Epinephelus malabaricus(Bloch&Schneider,1801)in southeast coast of India

Objective:To study the prevalence of philometrid nematode,Philometra spp.infected in the ovaries of Epinephelus malabaricus(E.malabaricus)from southeast coast of India.Methods:Totally 4801 fishes were collected from Mandabam,Tuticorin and Kanyakumari.The normal and infected ovaries were carefully removed from dissected fishes and the prevalence of nematode infection for each fish was examined.Then the nematode were carefully removed and washed in a 0.6%saline solution and fixed in 70%ethanol.Representative nematodes were cleaned with glycerin and fixed in a solution of 95%glacial acitic acid and 5%formalin for identification under light microscopy.Results:Of which 16.8%,16.2%and 14.7%parasitic prevalence was observed from Mandabam,Tuticorin and Kanyakumari respectively.The intensity of parasitic worms per fish varied from 1 to 8 with an average of 6.33±0.84.Nematode length varies from 7-22 mm with in average of(18.70±4.57)mm.The average length and weight of E.malabaricus were(332.950±77.792)mm and(513.30±169.46)g respectively.Conclusions:It can be assumed that females of this nematode are unable to attain gravidity in this host species,and consequently,E.malabaricus does not serve as the true definitive host of Philometra spp.Prevalence of infection and intensity of the nematode are highly effected by sucking blood,causing atrophy of developing ova in the ovary,fibrosis of ovarian tissue,increasing granulocytes and haemorrhages,and thus negatively affecting the reproduction of some species of E.malabaricus.