Control of common freshwater predatory fish, Channa punctatus, through Nerium indicum leaf extracts.

Laboratory evaluations were made to asses the piscicidal activity of ethyl alcohol extract of Nerium indicum leaf against predatory fish Channa punctatus and their ultimate mode of action on fish metabolism. Toxicity experiments show there was significant negative correlation between LC values
and exposure periods i.e. LC50 value decreased from 66.32 mg/L (24h) to 44.96 mg/L (96h).
Biochemical studies show that after exposure to sub lethal doses of alcoholic extract, pyruvate level and activities of acetylcholinesterase and cytochrome oxidase significantly decreased while lactate level and activities of alanine aminotransferase and aspartate amino transferase were significantly enhanced in both liver and muscle tissues of Channa punctatus. The alterations in all the above
biochemical parameters were significantly (P<0.05) time and dose dependent. There was a significant recovery observed in all the above biochemical parameters, in both liver and muscle tissues of fish after the seventh day of the withdrawal of treatment Thus it was believed that alcoholic extract of
Nerium indicum leaf can be used in aquatic environment for controlling predatory fish Channa punctatus population. Their piscicidal activity may be due to their adverse effect on respiratory as well as energy production of fish. The reversible nature of the piscicidal action could be advantageous in aquatic environment.

https://tspace.library.utoronto.ca/bitstream/1807/9176/1/tc04003.pdf

Piscicidal activity of alcoholic extract of Nerium indicum leaf and their biochemical stress response on fish metabolism

Effect of alcohol extract of a natural piscicide — Fruits of Zanthoxylum armatum DC. on Mg2+- and Na+, K+-ATPase activity in various tissues of a freshwater air-breathing fish, Heteropneustes fossilis

The effects of crude extract, pure extract, aqueous fraction of pure extract and lipid fraction of pure extract of air-dried leaves of Erythrophleum suaveolens as anesthetic on African sharptooth, Clarias gariepinus, and the African vundu catfish, Heterobranchus longifilis, fingerlings were studied. They were exposed to various doses of the extracts in tanks. The time for each fish to reach anesthesia were recorded. The two clariids were anesthetized in up to 3.5 g/L crude extract and recovered in the fresh water. Soaking the leaves for 24 hours or 48 hours produced no significant difference (P> 0.05) in the time to reach anesthesia for the African vundu catfish. These fingerlings reached anesthesia in significantly shorter time (P<0.05) (24.5 minutes at 2.4 g/L concentration) in the pure unseparated extract than in the crude extract (70.5 minutes at 2.4 g/L concentration). All fingerlings exposed to 4 g/L extracts did not recover. Those exposed to less than 3.5 g/L of plant material were anesthe...

Effects of Extracts of Dried Leaves of Erythrophleum suaveolens as Anesthetics on Clariid Catfish

Piscicidal plants of Nepal: Toxicity to air-breathing predatory fish (Ophiocephalus punctatus, Clarias batrachus and Heteropneustes fossilis) and the duration of risk to cultivated fish

Piscicidal plants of Nepal: Ripe fruit of Catunaregam spinosa (Thunb.) (Rubiaceae) and leaves of Polygonum hydropiper L. (Polygonaceae) as fish poisons

Augusthy Thevasia Kulakkattolickal

Papers

Piscicidal plants of Nepal: Toxicity to air-breathing predatory fish (Ophiocephalus punctatus, Clarias batrachus and Heteropneustes fossilis) and the duration of risk to cultivated fish

Piscicidal plants of Nepal: Ripe fruit of Catunaregam spinosa (Thunb.) (Rubiaceae) and leaves of Polygonum hydropiper L. (Polygonaceae) as fish poisons