Browsing by Author "Mosha, R. D."

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Antiviral activity of crude extracts of Synadenium glaucescens (Pax) against infectious bursal disease and fowlpox virus
(2013-04-10) Mabiki, F. P.; Mdegela, R. H.; Mosha, R. D.; Magadula, J. J.
The effect of crude extracts from different morphological parts of Synadenium glaucescens against infectious bursal disease virus (IBDV) and fowlpox (FP) virus using an in ovo assay were investigated. Viable 9 days embryonated chicken eggs were challenged with viral strains then treated with S. glaucescens extracts at concentration of 0.2 mg/ml. Un-inoculated group were saved as negative control and groups inoculated with virus and diluent saved as positive controls. The treatments were observed daily and embryo weights were measured 5 days post-inoculation. Embryo survival and mean embryo weight were significantly higher (P ≤ 0.001) in groups treated with S. glaucescens extracts than the positive control. More than 50% of the extract prevented death and deformation of embryo and formation of pock lesions in embryos. Furthermore, the treatments with ethanolic extract of the root bark demonstrated significantly higher mean embryo weight compared to other extract for both viruses (P ≤ 0.001). The mean embryo weights from eggs challenged with infectious bursal disease virus and fowlpox virus treated with the extract were 6.3 ± 2 and 5.9 ± 0.5 g, respectively. These findings demonstrate potential and feasibility of using S. glaucescens extracts for treatment of the viral diseases. Furthermore, it validates the ethnoveterinary exploitation at community level.
Environmental and Health Impacts Associated with Usage of Agrochemicals in Mindu Dam Catchment Area, Morogoro, Tanzania
(African Journal Online, 2013-01-19) Mdegela, R. H.; Mosha, R. D.; Ngowi, H. A.; Nonga, H. E.
A field based study was conducted during 2004 – 2006 to assess the environmental, human and animal health risks associated with usage of agrochemicals in Mindu dam catchment area (MDCA), in Morogoro, Tanzania. Heads of 268 households were interviewed using a questionnaire with structured and semi-structured questions. Fertilizers, insecticides and fungicides were the most commonly used agrochemicals in tomato production, which was the main crop cultivated. Endosulfan was the only organochlorine pesticide used in vegetable production. The majority of the farmers purchased agrochemicals that were repacked in unlabelled non-original containers, which were later reused for domestic purposes. About 73% of the farmers applied agrochemicals without protective gears. High risk groups to agrochemical exposure in the area were men, retailers and children. Farmers’ perceived impacts of agrochemical usage included getting sick, deaths of people and animals and environmental pollution. Information obtained from this study was used to identify appropriate foci and target groups for interventions to reduce the health risks associated with the usage of agrochemicals in the area. This assessment identified three foci and target groups for interventions: training of farmers on good agricultural practices, strengthening agricultural extension services, and reinforcing regulatory services.
Influence of 17a-ethynylestradiol on CYP1A, GST and biliary FACs responses in male African sharptooth catfish (Clarias gariepinus) exposed to waterborne Benzo[a]Pyrene
(Springer Science+Business Media,, 2006-11-01) Mdegela, R. H.; Braathen, M.; Correia, D.; Mosha, R. D.; Skaare, J. U.; Sandvik, J.
Dose dependent effects of Benzo[a]pyrene (BaP) on cytochrome P4501A (CYP1A), glutathione- S-transferase (GST) and fluorescent aromatic compounds (FACs) metabolites biomarker responses were studied in African sharptooth catfish (Clarias gariepinus) following 24 h of waterborne exposures. Based on biomass of C. gariepinus in different tanks, BaP concentrations of 1.60, 3.44, and 18.21 lg/L that corresponded to 0.5, 1.0, and 5.0 mg/kg body weight were used. Significant induction of EROD activities in gill filaments was observed at all doses and the accumulation of FACs metabolites in bile was significantly different between groups. Accumulation of FACs metabolites in bile strongly correlated (r2 = 0.99) with BaP doses. Hepatic EROD activities were undetectable and no effect on GST activities was observed. The highest dose of BaP from the dose dependent study was further studied to assess the interactive and temporal responses of C. gariepinus on CYP1A, GST, and FACs metabolites biomarkers following exposure to either BaP alone, 17a-ethynylestradiol (EE2) alone or a combination of both compounds at concentrations of 54.17 lg/L for BaP, 51.38 lg/L for EE2 and 54.44 lg/L for each of both compounds. Based on biomass in each tank, these concentrations corresponded to 5 mg/kg body weight. While a group of six fish was sacrificed on day 0 from the control tank only, other groups of six fish were sacrificed after 1, 3, and 6 days of exposure from the control and exposed groups. Maximum induction of gill filament and hepatic EROD activities was observed after 1 day of exposure. Both EROD activities in gill filaments and liver were significantly induced by exposure to BaP alone or co-administration with EE2. Gill filament EROD induction was significantly inhibited (50%) by co-administration of BaP and EE2 compared to administration of BaP alone. Levels of FACs in bile for BaP and BaP + EE2 exposed groups were significantly different from the control at all doses and time points. A significant induction of GST activities was observed in fish exposed to BaP and BaP + EE2 after 3 days. Exposure to EE2 alone caused significant induction of this enzyme after day 6. This study reports for the first time the significant antagonistic influence of EE2 on BaP in gills of fish following waterborne exposures. The results also indicate that chemical mixtures may affect biomarker responses differently from compounds administered alone and that the sensitivity of CYP1A to interactive chemicals is different in gills and liver.