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The ichthyofauna diversity of the Jebba Hydroelectric Power (HEP) Dam, Jebba, North-central Nigeria was studied. Fishes were sampled for 24 months using gill net, hook and line, and cast net. Individuals were identified using morphological and molecular (mitochondrial Cytochrome c Oxidase subunit I) data. A total of 9605 freshwater fishes were recorded during the sampling period. The use of an integrative taxonomic approach enabled the identification of 83 species belonging to 42 genera. Additionally, the study recorded three unidentified species – Ctenopoma sp, Malapterurus sp., and Protopterus sp. Analyses showed that individuals belonging to families Cichlidae and Mochokidae dominated the dam. The diversity analyses revealed relatively high fish diversity during the rainy season at the downstream section of Jebba HEP dam compared to the upstream section. The study, therefore, showed the presence of a diverse fish community comprising high species richness and diversity across the Jebba HEP dam. Finally, we recommend proper biodiversity monitoring and assessment of freshwater fish diversity across Nigeria. In addition, the use of an integrated taxonomic approach is recommended for appropriate species’ identification and studies of freshwater fishes from Nigeria.

Pollution of water bodies in most developing countries is of grave concern since toxic pollutants interact with the genetic blueprints of aquatic organisms leading to a variety of illnesses. In this study, histological changes in the gills, liver and kidney as well as the genotoxic effect of water sample from Apodu reservoir, were investigated in the peripheral erythrocytes of cultured catfish (Clarias gariepinus) using micronucleus assay. They were exposed to the water sample for a period of 3, 7 and 14 days. The physico-chemical (pH, temperature, transparency) and heavy metals analysed (Ca>Mg>Fe>Zn>Mn>Cu>Ni=Pb=Cd=Cr) were all within the acceptable limit permissible. However, the micronucleus test shows statistically significant (p<0.05) induction of micronuclei and nuclear abnormalities as compared to the control (borehole water). The histopathological analysis shows some mild alterations in the organs such as distortion and infiltration of lymphocytic cells of the gills. We also reported mild distortion of hepatic tissue of the liver as well as abnormal nephron and glomeruli with congestion and vascular dilation of the kidney. These alterations might be due to anthropogenic activities that pollute the water body. Therefore, the influx of agricultural and domestic waste into the Apodu reservoir should be discouraged as part of remediating efforts.

Drug resistance in malaria infection is a serious public health challenge. Thus, scientific search for alternative treatment measures among the local medicinal plants is exigent. We therefore investigated the anti-plasmodial efficacy and genotoxicity of the methanolic leaf and stem extracts of Alstonia plant at varying concentration (200 mg/kg, 400 mg/kg and 600 mg/kg) in mice infected with chloroquine sensitive Plasmodium berghei. The phytochemical screening of the extract revealed that leaf sample contained significantly higher secondary metabolites, except saponins (p<0.05). Anti-plasmodial activities of the two extracts were duration and dose-dependent. Stem bark extract showed higher curative potential with inhibition rate of 56.71% at 400 mg/kg whereas, leaf extract was efficient at 600mg/kg with 52.15% inhibition rate. Stem bark extract at 400 mg/kg improved the enzymatic activities of the mice; it lowered serum ALT (6.88±4.42) and increased liver ALT (41.07±5.56). Similarly, 400 mg/kg leaf extract showed highest AST (70.65±4.00) and ALT (44.65±7.83) activities in the kidney and liver respectively. Analysis of genotoxicity revealed that micronucleus and abnormal (binucleated, notched and blebbed) were prevalent among the experimental mice which increased significantly (p<0.05) at all concentrations except at 600mg/kg leaf extract. Therefore, this present study indicates that both leaf and stem bark extracts of A. boonei possess anti-plasmodial activity and are less genotoxic when compared with standard drug.

Indiscriminate solid waste disposal to the environment without proper treatment poses a serious threat to the public health. This study was carried out to investigate genotoxicity of the raw and simulated leachates samples collected from Amilegbe municipal dump site located in Ilorin metropolis in Nigeria. Some of the physicochemical properties of both raw and simulated leachate samples were determined. Mice were exposed to 1%, 2.5%, 5%, 10% and 25% (raw leachate) and 1%, 5% and 10% concentrations (simulated leachate) respectively for 35 days. Distilled water and colchicine were used for negative and positive control respectively. Two standard genotoxicity tests namely abnormal sperm-head morphology and micronucleus (MN) assays were used to assess possible genotoxicity of the raw and simulated leachates samples. Sperm head morphology assay showed some abnormalities (folded, amorphous, banana shaped, two tails, pin tail among others) and the frequencies of the abnormalities increases was concentrationdependent. Congestion, necrosis, degeneration and appearance of vacuolation were observed in the histopathological analysis of the liver. The histopathological changes were also more pronounced with higher concentrations of raw and simulated leachates. MN and abnormal nuclei frequencies also showed statistically significant differences (p>0.05) such that MN and other nuclear abnormalities reached the maximum at the highest concentration (25% >10% >5% >2.5%>1%). This study shows that the raw and simulated leachates contain potentially genotoxic and cytotoxic substances capable of causing DNA damage. ©JASEM https://dx.doi.org/10.4314/jasem.v21i5.11

Cancer is a public health problem worldwide, affecting all categories of persons. It is the second common cause of death in developed countries and among the three leading causes of death in developing countries. Due to its genetics and medical importance, study on its incidence is germane. In the present study, 74 different cancers of 2,246 (n = 891 male and n = 1355 female) cancer patients within the age of 1-105 in Nigeria were retrospectively reviewed using the data from University of Ilorin Teaching Hospital (UITH). The overall profile of the categories showed the leading position of breast cancer, followed by cancer of the digestive system (32.29% and 19.67%, respectively), while Kaposi sarcoma, endocrine system and brain cancers were among the rare or least recorded (<1.0% incidence rate). Furthermore, the trend showed a high prevalence during 2011 and 2015 (>13% and >11%) than any other year within the study, while the lowest incidence was recorded in 2016 (<6%). Predisposing factors like tumorigenesis, immune system, biological stressors as well as gene-environment interaction and low life expectancy could influence the risk of different groups of cancer. Therefore, future investigations should be targeted on risk factors related to those considered rare so as to provide useful information about possible signs and symptoms for diagnosis before it escalate.

Fish can be considered as a good organism for bio-indicator in aquatic habitats as they accumulate contaminant from the water bodies through food. Aquatic ecosystem pollutants response in fishes can lead to biochemical changes and histological alterations. This present the need in assessing ecological and public health effect of toxicity in Asa river on the selected fish samples that are commercially important in the environment. Two stations of Asa river were selected where water and fish were collected for physicochemical parameters of the water, enzymatic and histological investigations in the laboratory in April, 2019. The heavy metals of the water in Unity area of Asa river was higher than that of the standard limit and Asa reservoir. There was an increase in the ALT, AST and ALP biochemical analysis carried out on Oreochromis niloticus and Clarias anguillaris with reduction in total protein level in Unity station. The histopathology of the gills of both Clarias anguillaris and Oreochromis niloticus found in Unity station of Asa river revealed thinner and loner secondary lamella in degenerating secondary lamella and mildly distorted cartilage with epithelial lining in Clarias anguillaris. Hence, proper management of the river is necessary to restore the ecology and make the water fit for use.    

Cichlids are among the economically important which serve as a source of food for people ‎around the world. A deep understanding of the population structure and genetic diversity of ‎cichlids are vital for initiation of conservation policies and sustainable aquaculture. There is ‎paucity of information on the patterns of genetic variations among and within cichlids in ‎North-central Nigeria. This study, therefore, investigated population genetic structure of ‎Coptodon zillii, Oreochromis niloticus, and Hemichromis fasciatus collected from different ‎freshwater bodies in North-central Nigeria. Genomic DNA was extracted, and five highly ‎polymorphic RAPD primers were used for RAPD-PCR amplification and genotyping of the ‎fish. Genetic polymorphism within and between the three tilapia species were examined. ‎Percentages of polymorphism loci, pairwise population matrix, analysis of molecular variance ‎‎(AMOVA), and genetic distances of cichlid populations were determined using standard ‎methods, and dendrograms were constructed using an un-weighted pair group method of ‎arithmetic mean (UPGMA). Overall, percentages of estimated molecular variance within and ‎among C. zillii, H. fasciatus and O. niloticus populations were 5% and 95%; 4% and 96% and ‎‎13% and 87%, respectively. Our results suggest that the three cichlids have close evolutionary ‎relationship and there were no distinct genetic differences on the basis on sampling locations. ‎C. zillii and H. fasciatus are more genetically closer than O. niloticus. This study concludes that ‎RAPD is useful in studying the population genetic structure of cichlids. This study therefore ‎recommends conservation of genetic pool of cichlid species through proper maintenance and ‎restoration of polluted habitat to guarantee sustainable fishery production. However, markers ‎such as microsatellite DNA can be assayed in further studies for better results‎.