SummaryThe parasitic infections of 125 anurans belonging to 13 taxa from Ase community in Delta State in the Niger Delta of Nigeria was investigated. An overall prevalence of 77.6% was recorded and the 32 parasites recovered included one pentastomid, four cestode, four monogenean, ten digenean and thirteen nematode taxa. Among the anurans examined, Ptychadena bibroni harboured the highest number of parasites. Most of the parasites encountered were adults but some occurred as larvae, which either used the amphibians as intermediate or transport hosts. Hylarana galamensis is considered an accidental host for the larval brachylaimid trematode and, a new host record for the larval strigeiod while Polystoma galamensis infection of this frog is made for the fi rst time outside the savannah biotope. Hymenochirus sp. is a new host record for Progonimodiscus colubrifer. Two Foleyellides spp., one occurring in Hyperolius concolor, Afrixalus fulvovitattus and Sclerophys regularis and the other in H. galamensis occur in the study area.

Background: Estimate shows that about one billion people rely on fish as primary source of animal protein. Currently, the global record portraying Nigeria as the largest producer of fishes (over 15,489 t per annum) in Africa is being threatened by the presence of various species of parasites that consider fishes as suitable definitive hosts. Control strategies will, however, be ineffective if there are scanty epidemiological data. Based on this premise, we undertook this present study to identify species of parasites, their prevalence, mean intensities, and indicators of infection of Coptodon zillii in Zobe Dam in the study area. Methodology: Study design was cross-sectional in nature with sample size of 411 fish. The data collected from this study were entered into Microsoft Excel 2010 and analyzed with Epi Info™ 7. After evisceration and standard histological protocol, recovered parasites were identified as Acanthogyrus tilapiae using standard identification keys. Results: Major findings of this study show that the overall prevalence and mean intensity of piscine acanthocephaliasis were 16.30% (12.94-20.31) and 1.46 (1.19-1.72) parasites per Coptodon zillii respectively. Prevalence and mean intensity of Acanthocephala infection significantly increased as the length of fish increased (χ 2 = 14.001; p = 0.0002) with fish having a length range of 17.0-23.9 cm being about four times more likely to be infected compared to those with 11.0-16.9 cm length [COR (95% CI) 3.78(1.81-7.89)]. In like manner, there was a significant increase in the prevalence of infection as the weight of fish increased (χ 2 = 6.055; p = 0.0139) with those belonging to weight category 190.1-250.0 g being three times more likely to be infected compared to those in 70. 1-130.0 g category [COR (95% CI) 3.38 (1.05-10.84)]. Besides, Fulton's condition factor was a major determinant of infection with piscine acanthocephaliasis (χ 2 = 13.981; p = 0.0002). Conclusion: Based on the findings of this study, it could be concluded that length, weight, and condition factor were indicators which contributed substantially to piscine acanthocephaliasis in Zobe Dam. In view of reports indicting acanthocephalans as biomarkers of lead (Pb) pollution, further study is, however, recommended to ascertain this hypothesized heavy metal pollution in the study area and its environs.

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The parasitic infections of market derived Osteolaemus tetraspis from the rainforest and Varanus ornatus from locations in the savanna-mosaic and the rainforest of southern Nigeria were investigated. Parasites recovered from O. tetraspis included members of the Pentastomida, Trematoda and Nematoda. An undescribed pentastomid belonging to the family Sebekidae was recovered from O. tetraspis. The same parasite was also found to parasitize V. ornatus from the rainforest. Other parasites found in O. tetraspis were Pseudoneodiplostomum thomasi, Dujardinascaris sp. and larva of a Camallanus sp. Varanus ornatus from the rainforest and the derived savanna had some parasites including Duthiersia fimbriata, an unidentified pseudophyllidean cestode and Tanqua tiara in common. Cosmocerca ornata and Oswaldocruzia hoepplii were restricted to hosts from the derived savanna while the unidentified trematode occurred only in lizards from the rainforest. The unidentified pseudophyllidean cestode bears a close resemblance to Probothriocephalus, a cestode previously reported only from deep water teleosts. Pseudoneodiplostomum thomasi and Duthiersia fimbriata are new locality records for Nigeria.

Of 150 specimens of the gastropod snail Limicolaria aurora examined from the Edo and Delta states of Nigeria, 63.4% were infected with larval digeneans comprising mother sporocysts (12.1%) daughter sporocysts (20.4%) cercariae (43.1%) and metacercariae (24.5%). Attempts to experimentally infect three 14-day-old chicks (Gallus domesticus) and two laboratory-bred 4-month-old mice (Mus musculus) by oral feeding and peritoneal injection with cercariae were negative, although experimental infections of chicks via a cloacal drop yielded 62 immature and 37 mature worms from the intestinal caeca and ileum. The worms were identified as Brachylaima fuscatum (Trematoda: Brachylaimidae). The study also revealed that L. aurora acts as an intermediate host for B. fuscatum, in addition to Eulota sp., Helix sp., Helicella sp., Oxychilus sp. and Agrolimax sp.