| the use of the urogenital papillae of male feral african sharptooth catfish (clarias gariepinus) as indicator of exposure to estrogenic chemicals in two polluted dams in an urban nature reserve, gauteng, south africa. | the african sharptooth catfish (clarias gariepinus) is indigenous to south africa where it is commonly found in calm waters such as lakes, streams, rivers, swamps and floodplains. the males of this gonochoristic species can be readily distinguished from females via a distinct elongated urogenital papilla with a pointed tip, located just behind the anus. this structure is an androgen controlled secondary sexual characteristic and could potentially be affected by chemicals displaying endocrine dis ... | 2013 | 23127382 |
| histopathological alterations in the liver of the sharptooth catfish clarias gariepinus from polluted aquatic systems in south africa. | there is a need for sensitive bio-monitoring tools in toxicant impact assessment to indicate the effect of toxicants on fish health in polluted aquatic ecosystems. histopathological assessment of fish tissue allows for early warning signs of disease and detection of long-term injury in cells, tissues, or organs. the aim of this study was to assess the degree of histopathological alterations in the liver of c. gariepinus from two dams in an urban nature reserve, (gauteng, south africa). two dams ... | 2009 | 18528907 |
| on cestode and digenean parasites of clarias gariepinus (burchell, 1822) from the rietvlei dam, south africa. | sharptooth catfish, clarias gariepinus, from the rietvlei dam near pretoria, south africa were examined for internal platyhelminth parasites. two adult cestodes, polyonchobothrium clarias (stomach) (prevalence 71%, mean intensity = 5, n = 7) and proteocephalus glanduliger (anterior intestine) (prevalence 14%, mean intensity = 2, n = 7), were found in the gut while metacercariae of one larval digenean, ornithodiplostomum sp. (prevalence 14%, mean intensity = 140, n = 7), were found encysted in th ... | 2006 | 16958260 |
| nematode parasites of clarias gariepinus (burchell, 1822) from the rietvlei dam, south africa. | catfish, clarias gariepinus, from the rietvlei dam near pretoria, south africa were examined for nematode parasites. two species, procamallanus laeviconchus in the stomach and contracaecum spp. larvae in the abdominal cavity, were found. the morphology of these species, based on light and scanning electron microscopy, and how they compare with previously described specimens are discussed. infection rates were mild compared to previous surveys although contracaecum spp. had a high prevalence of 8 ... | 2006 | 16958258 |
| histological evidence of intersex in feral sharptooth catfish (clarias gariepinus) from an estrogen-polluted water source in gauteng, south africa. | this is the first histological evidence of intersex in a fish species inhabiting a south african water source. one hundred catfish (clarias gariepinus) were collected randomly from the marais dam (md) and the rietvlei dam (rvd) in the rietvlei nature reserve (rnr), south africa. these dams drain water from a stream that receives effluent from industrial sites, agricultural activities, informal settlements, and municipal treatment plants. each fish was evaluated macroscopically and had blood draw ... | 2004 | 15526264 |