INCIDENCE OF LERNAEID PARASITE IN CATLA CATLA ON A FISH FARM

摘要

Two hundredfishes (Catla catla) were examined for Lernaeid ectoparasites at Matti-tal Fish Farm, Multan during 2008. Four species of the genus Lernaea recorded were L. polymorpha, L. cyprinacea, L. oryzophila and Lernaea spp. The overall prevalence ofLernaea polymorpha was (46%) followed by L. cyprinacea (37.5%), L. oryzophila (8%) and of Lernaea spp., (1%), respectively. The relationship between body weight and Lernaeid parasites showed that prevalence of L. polymorpha, L. cyprinacea and L. oryzophila was highest in weight group of 801-1200g (75, 75 and 25%) and lowest in weight group of l-400g (44.68, 35.62 and 6.91%). While for Lernaea spp., maximum prevalence was observed in weight group of 1-400g (1.06%) the parasite was absent in other body weight groups. The difference was statistically significant (P<0.05). The relationship between body length and Lernaeid parasites revealed the maximum infestation of L. polymorpha, L. cyprinacea, L. oryzophila and Lernaea spp., 90, 80, 20 and 10% in length group of 31-40cm, and it was minimum (16 66, 11.40, 7.01 and0%) in ll-20cm group, respectively. The difference was statistically significant (P<0.05).