Co-infection and morphometrics of three clinostomatids (Digenea: Clinostomatidae) in Tilapia guinensis Bleeker, 1862 from Opi lake, Nigeria

Co-infection and morphometrics of helminth parasites of Tilapia guinensis in Opi Lake (GPS N06.75275*, E007.49104*), were studied from (Nov 2007– Oct 2008) using multiple fishing gear techniques; cast nets, hook and line, and seine nets (150 mm – 200 mm). The parasites recovered were C. tilapiae, C. complanatum and E. heterostomum. The prevalence was low, indicative of parasitic infection in the wild. Prevalence of (33.9 %) was recorded in C. complanatum, (7.2 %) in E. heterostomum and (12.6 %) in C. tilapiae. But high mean intensity was suggestive of heavy parasite burden; C. complanatum (4.8), C. tilapiae (2.8), and E. heterostomum (5.1). Morphometrics of the parasites showed no significance difference in the distance between oral and ventral suckers. However, they differed in all other parts significantly (p < 0.05). In the rank-abundance curve for parasite communities, C. complanatum was most abundant (pi 0.63). Differential parasitic effects were due to selection for relatively better adaptiveness to host’s microhabitats, more population size, better host location, and larger body size. Consequently, this resulted in a trade-off between larger morphometric parts and population size among the parasite

Co-Parasitism And Morphometrics Of Three Clinostomatids (Digenea: Clinostomatidae) In Sarotherodon melanotheron From A Tropical Freshwater Lake

In ever competitive environment of nature, evolution of most attributes of an organism - anatomy,physiology, and behaviour are determined by the environment through selection. The same is the microhabitats of Sarotherodon melanotheron where three Clinostomatids; Clinostomum tilapiae, Clinostomum complanatum, and Euclinostomum heterostomum, were recovered from Opi Lake (GPS N06.75275*, E00749104*), were studied from (November 2007– October 2008) using multiple fishing gear techniques; cast nets, hook and line, and seine nets (150 mm – 200 mm), showed signiicant dfference (p < 005) in all other anatomical parts but the distance between oraand ventral suckers. The prevalence was low; (20.8 %) was recorded in C. complanatum, (6.4 %) in E. heterostomum and (21.1 %) in C. tilapiae. But mean intensity was high which was suggestive of heavy parasite burden; C. complanatum (2.7), C. tilapiae (5.8) and E. heterostomum (5.1). In therank-abundance curve for parasite communities C.tilapiae was more abundant than the other twospecies. Differential parasitic implications was due o selection for relatively better adaptiveness tohost’s microhabitats, more population size, better host location, and larger body size. Consequently, this resulted in a trade-off between larger morphometric parts and population size among the parasites.Key words: Clinostomum sp, co-parasitism, Morphometrics, E. heterostomum, Opi Lake, Selectio

First Record of Co – Infection of Three Clinostomatid Parasites in Cichlids (Osteichthyes: Cichlidae) in a Tropical Freshwater Lake

The present study investigated the effects of first record of co-infection of three Clinostomum sp.; Clinostomum Complanatum (Rudolphi, 1819), C. tilapiae (Ukoli, 1966), and Euclinostomum hetereostomum (1809) in Tilapia zilii. There was differential parasitic effects resulting in selection for relatively better adaptiveness to hosts microhabitats, more population size, and frequent host location of these parasites during the one year survey (Nov 2007- Oct 2008) in Opi Lake, Nigeria. Prevalence of 9.4 % was recorded in C. complanatum, 10.4 % in E. heterostomum and 4.8% in C. tilapiae. The parasites were recovered from three major microhabitats of buccal cavity, skin and eye