Balanites aegyptiaca or Desert date is a common plant in all dry lands of Africa and South Asia. Some parts of the plant are used as fish poisons but not poisonous to man. It is also used as medicine or food in humans as well as insect repellent. Four parts of the plant were phytochemically and proximately screened to determine whether the bioactive compounds can be utilized in sedation or anaesthetization of fish as well as supplementation of fish nutrition. The root, stem bark, leaf and fruit of the plant were screened using petroleum ether, methanol, chloroform ethanol and water as solvents. Proximate analysis to determine proximate composition of the parts of the plant was also conducted. Phytochemical analysis revealed the presence of alkanoids, flavonoids, tanins, saponins, terpens & steroids, cardiac glycosides, balsam, carbohydrates, phenols in the root and fruit. There was absence of alkanoids, flavonoids, balsam, and carbohydrates in the stem bark. The leaf confirmed the aforementioned phytochemicals except cardiac glycoside. The proximate analysis showed low percentage crude protein composition in all the plant parts [Leaf (22.94%), fruit (15.63%), root (12.81%) and stem (6.94%)]. Moisture content of the plant was also low with fruit having the highest (4.56%) and the leaf with the lowest (2.69%). The results of this work provide evidence that the bioactive compounds of the root, leaf and fruit could be utilized in sedation and anaesthetization of fish while the proximate composition was not suitable for supplementation in fish nutrition

One of the many biomarkers for determining the effects of pollutants on fish is changes in organ histopathology. Leaves of Balanites aegyptiaca have been reported to have phytochemicals with fish anaesthetic property. This study sought to determine the effect of graded acute concentrations (200.00, 250.00, 300.00.350.00 and 400.00 mg/L) of B. aegyptiaca on histopathology of gills, kidney and liver of mixed sex of Oreochromis niloticus fingerlings. A total of 120 O. niloticus fingerlings (mean weight 23±0.03 g and mean total length 12.50±0.39 cm) were exposed to the plant extract. Paraffin wax method and haematoxylin-eosin staining techniques of tissue processing were adopted for the examination of the gills, kidney and liver. Dose-dependent histopathological changes were observed in the three organs (gills, kidney and liver) i.e. histopathological alterations increase with increase in concentration of the plant extract. Gills showed lamellae fusion, haemorrhage, desquamation, atrophy and secondary lamellae erosion while kidney and liver indicated atrophy, necrosis, haemorrhage, hyperplasia and hypertrophy. Structural alterations were evident in the gills, kidney and liver of O. niloticus fingerlings exposed to the concentrations of aqueous crude leaf extract of B. aegyptiaca therefore it should be used with caution during fish anaesthesia. Keywords: Histopathology; Gill; Kidney; Liver; Balanites aegyptiaca; Oreochromis niloticus.

Background: Increased rate of water pollution has detrimental effects on the health of fish and other aquatic organisms. This invariably affects humans by causing food insecurity, hunger and poverty. In an effort to curb this menace, this study investigated the effects of crude tuber peel extract of Tacca leontopetaliodes on the biochemical and histological parameters of Clarias gariepinus. Methods: Acute toxicity (96 hr . LC50) test was conducted after a range finding test from which definitive test concentrations of 5.00, 4.00, 3.00, 2.00, and 1.00 g/L were obtained with 0.00 g/L as control. One hundred and twenty (120) mixed sex C. gariepinus fingerlings (mean weight, 12.5 g ± 0.5; length, 13.2 cm ± 0.5) were administered definitive concentrations of crude tuber peel extract in duplicate replication. Water quality parameters (pH, dissolved oxygen, free carbon dioxide, alkalinity), tissue enzymes (Alkaline phosphatase (ALP), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST) and histopathological assessments were analysed using standard procedures. Results: Physico-chemical parameters (pH, dissolved oxygen, free carbon dioxide and alkalinity) of test tanks containing graded concentrations of T. leontopetaliodes were significantly altered (p<0.05) compared to the control tank. Similarly, the profile of hepatic enzymes (ALP, AST and ALT) displayed marked progressive dose-dependent increase levels relative to the control. Histopathological examination revealed graded deterioration of gills and liver architecture with increase in the strength of the extract T. leontopetaliodes Conclusion: The crude tuber peel extract of T. leontopetaliodes is toxic to fish, thus, washing, processing and discard of T. leontopetaliodes in and around riparian systems should be discouraged.

Fishing with Albizia gummifera is gaining more popularity than Tephrosia vogelii by local fishermen of Mangu Local Government Area, Plateau State and other parts of Nigeria, because of its productiveness and availability. Acute toxicity of aqueous extracts of leaf and bark of T. vogelii and A. gummifera were conducted on C. gariepinus fingerlings in static non-renewable bioassay. Dissolved Oxygen (DO) mg/L, pH and Temperature (°C) were monitored daily throughout the period by using ExStik® DO600 meter. Definitive acute concentrations of 140, 120, 100, 80, 60, 0.00 mg/L; and 600, 525, 454, 375, 225 and 0.00 g/L as control of aqueous bark and leaf extracts in mg/L for A. gummifera and T. vogelii were used respectively. The result of the water quality parameters of fishes exposed to various plant toxicant concentrations of the plants showed no variation in all the studied water parameters compared with the control treatments. The percentage mortality of fishes was observed to decrease with decrease in toxicant concentrations in both plants. The 96hrs LC10; LC50 and LC99 values with confidence limits were of 61.21 (53.54 - 104.67) mg/L and 131.86 (104.67 - 166.10) mg/L; 94.58 mg/L (108.56 - 82.419) and 277.82 (220.54 - 349.98); and 208.46 (182.31 - 238.35) and 1074.73 (853.13 - 1353.82) of aqueous bark and leaf extracts of A. gummifera and T. vogelii to the exposed fishes, respectively. Lower lethal concentration values of A. gummifera indicated that it is more toxic than T. vogelii. Therefore, fishing with the A. gummifera should be regulated in order to preserve fish species in wild.