Length-weight relationships of five fish species in Epe lagoon, Nigeria

Length-weight relationship (LWR) of 320 fish populations covering 3 families, 4 genera and 5 species inhabiting Epe Lagoon, were studied. The fishes (Clarias gariepinus (Burch), Illisha africana Bloch), Chrysichthys nigrodigitatus (Lacepede), Chrysichthys walkeri (Gunther) and Ethmalosa fimbriata (Bowdich)) were obtained from fish landing site at Epe market from November 2001 to October 2002, and January to December 2003. The parameters a and b of the length-weight relationship of the form W=aLb and condition factor (c.f.)=W100/L3 are presented for the five fish species. The c.f. values significantly (

Impact of Effluents on Water Quality and Benthic Macroinvertebrate Fauna of Awba Stream and Reservoir

A study on the impact of effluent discharge on water quality and the benthic macro invertebrate fauna of the Awba stream and reservoir was carried out between April 2007 and May 2008. Benthic macro invertebrate and sediment samples were collected with a Van Veen grab, while physico-chemical parameters were sampled with Hach\u2019s Company Fish Farmers\u2019 Water Quality Test kit. Four stations were chosen for this study. A total of 4 taxa comprising 10 species of organisms were recorded. The abundance of these species and the physicochemical parameters at the various stations were significantly different (P<0-05). Dissolved oxygen was considerably lowest at Station 2 (1.38 \ub1 0.19mgl-1); a region of intense organic pollution during the study period. This was accompanied by high values of dissolved CO2 (20.0 \ub1 1.51mgl-1), total hardness (103.0\ub17.87mg (CaCO3)/l), ammonia-nitrogen (3.0\ub10mgl-1) and increased pH values (8.5\ub10.27). Water temperature values was also highest at this station (30.7\ub11.15\ub0C). The values obtained for the physico-chemical parameters and correlation values with the tested organisms indicated that changes in community structure had occurred as a result of changes in prevailing conditions in the habitat. The levels of trace metals (Zn, Mn, Cu, Pb, Ni, and Cr) were analyzed and there was no statistically significant difference in the values recorded between stations. The levels of these metals except zinc and manganese fell within the limits specified by USEPA as values recorded for zinc and manganese were higher than the acceptable limits specified by USEPA

Wildlife species diversity indices and seasonal distribution assessment in road-side markets of South-west Nigeria

Wildlife species are under serious exploitation by the rural populace in Nigeria because hu­man beings have understood their ecology. The need to update the existing knowledge of wildlife population is therefore essential. Twenty-three games markets along five Roads in South-west Nigeria were visited to document the wildlife displayed for sale. Two hundred and fifty copies of structured questionnaire were administered using systematic random sampling (odd) method for wildlife species information from market stakeholders. Direct method was counting for species and their numbers. Data generated were analysed through Species Diver­sity Indices Assessment. All emergent species were compared with International Union for Conservation of Nature (IUCN) abundance rating. Road seasonal distribution of the marketed wildlife was determined by percentages, standard deviation, standard error of mean, mean differences, t-test, and tests of significance and Diversity Indices. Results revealed that 69,398 wild animals were displayed. Also more wildlife were sold during rainy than dry seasons. Appropriate recommendations of government sensitization of rural and urban settlers against over-utilization of wildlife resources, encouragement of the public towards animal domesti­cation and others were made

Impact of Effluents on Water Quality and Benthic Macroinvertebrate Fauna of Awba Stream and Reservoir

A study on the impact of effluent discharge on water quality and the benthic macro invertebrate fauna of the Awba stream and reservoir was carried out between April 2007 and May 2008. Benthic macro invertebrate and sediment samples were collected with a Van Veen grab, while physico-chemical parameters were sampled with Hach’s Company Fish Farmers’ Water Quality Test kit. Four stations were chosen for this study. A total of 4 taxa comprising 10 species of organisms were recorded. The abundance of these species and the physicochemical parameters at the various stations were significantly different (P<0-05). Dissolved oxygen was considerably lowest at Station 2 (1.38 ± 0.19mgl-1); a region of intense organic pollution during the study period. This was accompanied by high values of dissolved CO2 (20.0 ± 1.51mgl-1), total hardness (103.0±7.87mg (CaCO3)/l), ammonia-nitrogen (3.0±0mgl-1) and increased pH values (8.5±0.27). Water temperature values was also highest at this station (30.7±1.15°C). The values obtained for the physico-chemical parameters and correlation values with the tested organisms indicated that changes in community structure had occurred as a result of changes in prevailing conditions in the habitat. The levels of trace metals (Zn, Mn, Cu, Pb, Ni, and Cr) were analyzed and there was no statistically significant difference in the values recorded between stations. The levels of these metals except zinc and manganese fell within the limits specified by USEPA as values recorded for zinc and manganese were higher than the acceptable limits specified by USEPA

Short Communication - Toxicity of Parkia biglobosa and Raphia vinifera extracts on Clarias gariepinus juveniles

Acute toxicity tests were carried out with aqueous and ethanolic extracts of two botanicals on Clarias gariepinus juveniles. 96-h LC50 values for Parkia biglobosa aqueous (AEPB) and ethanolic extracts (EEPB) were 2.8 and 2.4 ppm, respectively. While for Raphia vinifera aqueous (AERV) and ethanolic extracts (EERV), the values were 3.4 and 3.2 ppm, respectively. The resulting 96-h LC50 values showed that extracts of P. biglobosa were more potent than the extracts of R. vinifera and that EEPB was the most toxic. Histopathological changes in liver and gill of exposed fish showed subtle cellular damages like necrosis, lesions, oedema and hepatocytes

Toxicity of Raphia vinifera, P. beauv fruit extracts on biochemical composition of Nile Tilapia (Oreochromis niloticus, Trewavas)

Biochemical compositions (total protein = TP, total lipid = TL, globulin = Gl, albumin = Al and albumin/globulin = A/G ratio) of Oreochromis niloticus liver, kidney and brain exposed to 0.5 ppm aqueous extracts of Raphia vinifera (AERV) were investigated. The various biochemical compositions fluctuated with time of exposure to AERV. TP ranged between 0.91-4.64 mg/dl, Al between 0.41 – 3.02 mg/dl, Gl between 0.70-3.40 mg/dl, A/G between 0.20-3.50 mg/dl and TL between 571.3-998.2 mg/dl. Significant (