Browsing by Author "Adeogun, A. O."

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    Evidence of elevated levels of polychlorinated biphenyl congeners in commonly consumed fish from Eleyele Reservoir, Southwestern Nigeria
    (Sage Publishers, 2016) Adeogun, A. O.; Adedara, I. A.; Farombi, E. O.
    Environmental pollution of water, which is a source of cheap and affordable protein in the form of fish on which the population depends on, is of great concern globally. The present study assesses the levels of polychlorinated biphenyls (PCBs) congeners in sediments and six commonly consumed cichlid species from Eleyele Reservoir, Southwestern Nigeria. The results indicate that the concentrations of heavier PCB congeners are higher than the lighter congeners in both sediment and fish tissue. The predominant PCB congeners in the sediment samples from this site were PCBs 8, 44, 114, 101, 189, 196, 206 and 209. The concentration of PCB congeners increased with increasing molecular weight from hepta-PCB to deca-PCB in all fish species. The trend in accumulation of total PCBs in fish was as follows: Tilapia guineensis (2,531.1 + 74.6 ng/g) > Sarotherodon galilaeus (1178.7+68.5 ng/g) > Oreochromis niloticus > (891.8+49.6 ng/g) > Tilapia zillii (832.8 + 38.2 ng/g) > Hemichromis fasciatus (475.7 + 28.5 ng/g) > Sarotherodon melanotheron (333.2 + 26.1 ng/g). In summary, data from this study shows that the levels of PCBs in cichlid species from Eleyele Reservoir are higher than the threshold level of 0.023–0.047 ng g_1 recommended by United States Environmental Protection Agency. Such elevated PCB levels present significant health implications for human consumers and a threat to the resident fish communities.
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    SEM study on morphology and surface topography of wenyonia minuta woodland 1923 (cestoda: caryophyllidea) and the histopathological consequences on synodontis filamentosus (boulenger, 1901) from Lekki Lagoon, Lagos - Nigeria
    (2015) Akinsanya, B.; Hassan, A. A.; Adeogun, A. O.
    The SEM study on m orphology and surface topography of Wenyonia minuta was undertaken. The parasite was recovered from the intestine of Synodontis filamentosus. A total of two hundred and forty fi ve specimens of the fish host were exam ined.The fem ale specim ens (n =88) has a prevalence of 69.3% while the male specimens (n = 157) had a lower prevalence of 46.4%. The SEM description of the caryophyllidea cestode revealed the scolex to be fluke - like with four shallow longitudina l groove and flat pointed anterior end. The overall length of the scolex is 104250.97pm with a breadth of 653451.20pm .The furrow longitudinal groove were only observed on the dorsal side of the scolex. External protuberances were also reported in this study. The histopathological analysis shows m atting, lym phocytic infiltration of the lamina propria, goblet cell hyperplasia while some sections with no significant pathological changes were also observed
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    Susceptibility of Anopheles gambiae sensu lato (diptera: culicidae) to permethrin, deltamethrin and bendiocarb in Ibadan city, Southwest Nigeria
    (Maxwell Scientific Organization, 2013-03) Ibrahim, K. T.; Popoola, K. O.; Adewuyi, O. R.; Adeogun, A. O.; Oricha, A. O.
    This study was carried out to assess the resistance/susceptibility level of An. gambiae s.l, a major malaria vector in Ibadan metropolis, south west Nigeria, to two classes of insecticides approved by World Health Organization (WHO) for vector control. Anopheles larvae were collected from two communities (Ojoo and Bodija) within the metropolis and reared to adults. Two to three-day old, non-engorged female mosquitoes were exposed to discriminating dosages of 0.05% deltamethrin, 0.75% permethrin and 0.1% bendiocarb using WHO protocols and susceptibility test kits. Knockdown effect was recorded every 10 min and mortality scored 24 h after exposure. Species identification was by morphological characteristics only. The study revealed that the major malaria vector in Nigeria, An. gambiae s.l, were susceptible (mortality rate of 98.8%) to deltamethrin in Ojoo community, while Bodija recorded marginal susceptibility (87.5%). Both sites showed reduced susceptibility to permethrin and resistance to bendiocarb with 24 h post exposure mortalities ranging from 83.5 to 87.7% and 70.0 and 52.5%, respectively. The median Knockdown Time (KDT50) from 22-44.2 min for the pyrethroids (permethrin and deltamethrin), while that of carbamates (bendiocarb) range from 35.2 to 49.5 min. Resistance recorded in the field populations of An. gambiae s.l in Ibadan to bendiocarb was not observed in same population exposed to the pyrethroids (deltamethrin and permethrin) but with differential susceptibility. Therefore Bendiocarb may not be suitable as alternatives to mitigate pyrethroid resistance. A rationalised use of these insecticides coupled with regular monitoring of resistance status is essential to improve and evaluate the efficacy of the current vector control tools (ITN and IRS).