Histopathological effects of diethyl phthalate on Clarias gariepinus juveniles

The acute toxicity of diethyl phthalate to Clarias gariepinus fingerlings was investigated using static bioassays with continuous aeration over a period of 96 h. The LD50 of DEP for Clarias gariepinus was determined at 95% confidence limit for log toxicant concentration after 24 h, 48 h, 72 h and 96 h. The LD50 after 24 h, 48 h, 72 h and 96 h were 2.22, 2.73, 3.44 and 3.93 ìg/L, respectively. The LD50 for total death was estimated as 1.87 ìg/L. During the exposure period, the test fish was restless, swam erratically and hemorrhaging of the gill filaments was evident. These observations are indicative of stress due to effect of the diethyl phthalate on the fish. Sub acute Diethyl phthalate concentrations (30 ìg/L, 40 ìg/L, 60 ìg/L and 80 ìg/L) was obtained from the LC 50 of the acute study and the fish were exposed to the graded concentrations for period of 30 days. The fish were killed at 15 days interval and the liver and kidney were excised and the histopathological changes of DEP on the liver and kidney were determined by light microscopy. Pyknotic nuclei, destruction or fusion of tubules, condensation of the glomeruli and severe destruction of the tubule were observed in kidney tissue of fish. Cellular proliferation, congestion, necrosis, sinusoid enlargement, paranchymatous degeneration and fatty or glycogen degeneration were observed in the liver tissue of fish. The morphological changes of the tissues were dosage dependent

Evaluation of Larvicidal Activity of Leaf Extract of Lantana camara (Family: Verbenaceae) Against the Aedes aegypti Mosquito

Aqueous and ethanolic leaf extracts of Lantana camara were prepared and four different concentrations (0.3, 0.6, 0.9 and 1.2 g/ l) of both extracts were tested for larvicidal activity against the fourth instar larvae of Aedes aegypti for 24 hours in the laboratory. The 24-h percentage mortality rates ranged from 91.66 to 96.66 % in larvae treated with 0.3 to 1.2 g/L ethanolic L. camara leaf extract, respectively. The 24-h lethal time (LT50) and lethal concentration (LC50) were 6.8 h and 0.48 g/l, respectively. The aqueous extract did not result in more than 35 % larval mortality. The 24-h percentage mortality between the treatment groups were significantly different (P < 0.001) and also when compared with the control (P < 0.05). The result showed that the ethanolic extract was more lethal than the aqueous extract to A. aegypti larvae. The ethanolic extract also limited the pupation and the adult emergence that was inhibited by the ethanolic extract at 0.9 and 1.2g/L extract.Keywords: Aedes aegypti, Lantana camara, Leaf extract, Larvicide, Pupation, Emergenc

The Effect of Brewery Wastewater on the Total and Differential White Blood Cell Count of the Catfish Clarias Albopunctatus (Lamonte & Nicole)

The total and differential leucocyte count of Clarias albopunctatus exposed to Brewery wastewater for 21days were studied. The total leucocyte count increased (leucocytosis) in the wastewater-exposed fish. Compared with the control, there was significant lymphocytosis accompanied by monocytopenia and neutropenia in the treatment groups. These changes are indications of infection following exposure to the Brewery wastewater. Key Words: Clarias, wastewater, leucocytes, stress. Bio-Research Vol.1(2) 2003: 111-11

Tissue glucose and haemoglobin levels in the catfish Clarias albopunctatus during anaesthesia with ketamine hydrochloride

Adult Clarias albopunctatus (mean weight 64.8 ± 1.09 g) were subjected to anaesthesia for 72h with ketamine hydrochloride. The fish demonstrated uncoordinated and gyratory movements before reaching anaesthesia. The time taken to reach anaesthesia at the tested concentrations of ketamine differed in the treatment groups (P < 0.05). The haemoglobin, liver and plasma glucose concentrations were determined at 2, 4, 12, 48 and 72h interval. The mean liver and glucose concentrations were significantly elevated by ketamine hydrochloride (p < 0.05).The mean haemoglobin concentration was also significantly increased in the anaesthetized fish (p < 0.05). Both the liver and plasma glucose concentrations were significantly increased in the anaesthetizedsh. The result showed that ketamine hydrochloride appeared to have long-lasting anaesthetic effect on the fish.Keywords: Clarias, Anaesthesia, Ketamine hydrochloride, Haemoglobin, Glucos

Haematology and Erythropoietic Response in the Catfish, Clarias albopunctatus (Lamonte and Nichole 1927), Exposed to Sublethal Concentrations of Gammalin 20 (Lindane)

Haematological changes in the fish Clarias albopunctatus (Lamonte and Nichole, 1927) subjected to sublethal concentrations (0, 0.25, 0.5, 0.75, and 1.0 µg/L) of Gammalin 20 for 21 days were studied in a static bioassay renewal system. Compared with the control, the erythocytic count haematocrit values and haemoglobin concentrations were significantly reduced (P > 0.05) in the treatment groups. These parameters also differed in the treatment groups. There was significant leucocytosis (P > 0.05) in the fish exposed to sublethal concentrations of Gammalin 20. The Gammalin-20-exposed fish suffered macrocytic anaemia. Key Words: Haematology, Erythropoietic, Catfish, Gammalin Bio-Research Vol.1(2) 2003: 61-6

Effect of sublethal chromium on the haematology of the catfish Clarias albopunctatus (Nichols & LaMonte 1953)

No Abstract.Bio-Research Vol. 3(2) 2005: 45-4