Phytoremediation of diesel contaminated water (DCW) for freshwater fish Clarias gariepinus (12.6 ±1.4g and mean length 8.6 ± 0.7cm) was conducted at the research farm of the Enugu State University of Science and Technology Enugu. 180 juveniles were purchased and acclimatized for 7 days. A 24-hour range finding test determined the LC50 value of 1.2 mg/l DCW. A 96-hour static bioassay acute toxicity experiment was then conducted in plastic tanks with 10 fish in each, and diesel of different concentrations. Mortality rate was observed in the various test concentrations. The LC50 concentration was 0.12 mg/l, improved to 0.30 mg/L with MSE-treated diesel. Histopathology of the gills of affected fish showed elevated damage, necrosis, telangiectasia and oedema in DCW exposed fish, but limited damage in MSE-treated DCW exposed fish. The results of the experiment showed that diesel has detrimental effects on C. gariepinus and could cause high mortality at higher concentrations. Moringa seed extract (MSE) was used as a phytoremediant to ameliorate the mortality and gill histological damages of the experimental fish. Therefore, diesel contaminated water should be ameliorated to a safety level of 0.003 mg/l with MSE to protect fish species and other aquatic organisms.

The present study investigated the quality and oxidative enzyme activity of catfish Hetreoclarias hybrid semen fortified with cucumber fruit juice. The highest milt fertility rate of 75.56% was recorded in 10% CJ on day 3 compared with the least rate of 56.21% in control on day 1. The least hatchability rate of 57.56% was recorded on control day 1 compared with the highest value of 75.07% in 10% CJ on day 2. The highest milt survival rate of 99.07% was recorded among the control group on day 3 compared with the least survival rate of 87.48% recorded on day 1 of 20% CJ. There was a significant difference (P< 0.05) between the CAT control and treatments of CJ. The lowest value of 0.29 μmolemm-1 mg protein-1 was recorded in control on days 1, 2 and 4 compared with the highest value of 0.34μmolemm-1 mg protein-1 in 15% CJ on day 4. There was no significant difference in SOD activity between the control and CJ. Recorded values ranged between 0,026-0.165 Umole-1mgprotein-1 in 15% on day 2 and 10% on day 1 respectively. There was no significant difference in LPO activity between the control and CJ. However, a range of 0.022-0.135 mMoleTbarsmm-1 protein-1 was recorded on day 1in 10% and day 4 in 15% respectively. 20% and 10% Cucumber fruit juice showed greater values in fertility rate than control at respective storage periods of 3 days in Hetreoclarias hybridfish semen, and could in combination with DMSO improve its cryopreservation at short periods.