Effectiveness Test of Nicotiana Tabacum Extract on The Survival Rate and Histopathology of Clarias Gariepinus Infected With Aeromonas Hydrophila

Abstract

Motile Aeromonas Septicemia (MAS) caused by Aeromonas hydrophila threatens African catfish ( Clarias gariepinus ) aquaculture, driving economic declines. This study evaluated the therapeutic efficacy of tobacco ( Nicotiana tabacum ) leaf extract against MAS. A Completely Randomized Design was implemented with five immersion treatments: positive control (0 mg/L), 50 mg/L, 100 mg/L, 150 mg/L, and 200 mg/L, using three replications. Catfish fingerlings (7–8 cm) were challenged via intramuscular injection at the calculated lethal dose dilution (1:96 mL). The results demonstrated that immersion significantly increased fish survival. The maximum concentration of 200 mg/L achieved the highest survival rate at 80%, compared to 20% in the untreated positive control. Chronological observations revealed accelerated muscular re-epithelialization and wound closure by Days 4–5. Histopathological inspections of the liver confirmed substantial micro-anatomical recovery at the highest dosage. The treatment effectively restored polygonal hepatocyte boundaries and open sinusoids, eradicating the severe liquefactive necrosis and vacuolation observed in the infected control. In conclusion, immersion in 200 mg/L of Nicotiana tabacum extract serves as the most effective dose therapeutic threshold to mitigate Aeromonas hydrophila outbreaks.