Figure 1 - uploaded by J Roopavathy
Content may be subject to copyright.
Control gill of Labeo rohita; Primary gill lamellae (PGL), Secondary gill lamellae (SGL) Experimental group 10% Concentration of Azadiracta indica leaf extract on gill of fresh water fish Labeo rohita: The histology analysis in the control fish showed normal structure but in the treated fishes the gill exhibits the abnormalities like hyperplasia of secondary lamellae, disruption of structure of mucous layer, shrinkage of secondary lamellae, epithelial desquamation, blood lamellar congestion, aneurism, lamellae clumping, hyperplasia of secondary lamellae, curling of secondary lamelae, and destruction of epithelium.
Source publication
An investigation on the toxicity of biopesticidal plant Azardiracta indica aqueous leaf extracts to Labeo rohita. The LC50 value of Azardiracta indica aqueous leaf extracts was 1.1ml/lit respectively. The sub lethal concentration for Azardiracta indica was 0.11ml/lit and 0.33 ml/lit respectively. The fishes were exposed to the sub lethal concentrat...
Citations
An investigation on the toxicity of biopesticidal plant, Ziziphus jujube aqueous leaf extracts to Oreochromis mossambicus. The LC 50 value of Ziziphus jujube aqueous leaf extracts was 1.1ml/lit respectively. The sub lethal concentration for Ziziphus jujube was 0.11ml/lit and 0.33 ml/lit respectively. The fishes were exposed to the sub lethal concentration for a period of 15 days. At the end of 15th day the fishes were dissected and the liver were removed from exposed and control group of fishes. The tissues were processed and sectioned at 4µm and then were stained with Haematoxylin-Eosin. The observation of the slides was done under light microscope at 40x magnification and photographed. The exposed group showed histopathological changes in the tissues, such as: the parenchymal architecture of the liver is distributed and hepatocyte show dissociation, the hepatocyte appears swollen and cytoplasm appears granular. The hepatocyte nucleic become pycknotic. This result indicated that the aqueous extract of Ziziphus jujube has considerable impact on the liver of fresh water fish, Oreochromis mossambicus.
Phytoterapy has been used in aquaculture for disease control, especially the Terminalia catappa that demonstrated excellent antimicrobial potential. The aquaculture commonly uses the extract obtained at room temperature, but the hot aqueous extract (HAE) and its effects on the fish are still unknown. This study aimed to determine the lethal concentration (LC50) of HAE from Terminalia catappa in juvenile fish Colossoma macropomum as well as to evaluate hematological and histological parameters. Two extracts were obtained in different temperatures and submitted to HPLC. Despite both extracts presented the similar chemical compounds, HAE showed higher levels of compounds and then it was selected. For acute toxicity test, six different extract concentrations (0.00, 0.10, 0.20, 0.30, 0.40, and 0.50 g/L) in triplicate was used. At the end of the experiment, all fishes were submitted to hematological and histological analysis. The LC50 was determined using trimmed Spearman-Karber method, and water quality (pH, temperature, DO, electrical conductivity, and ammonia) were measured. The results were submitted to ANOVA followed by Tukey’s test (p < 0.05). The HAE showed LC50 of 0.41 g/L with changes on water parameters, such as pH and conductivity, as well as the fish behavior. HAE also altered hematologic parameters and showed histopathological changes on the gill and liver using high concentration of the extract or longtime exposure in low extract concentrations. Despite HAE showed higher concentration of compounds, it remains considered as a practically non-toxic product. Nonetheless, water quality, hematological, and histological alterations must be considered to determine concentrations and strategies of application in vivo.
