UTTAR PRADESH JOURNAL OF ZOOLOGY

Disease outbreaks increase proportionally with increasing intensive aquaculture. It is well known that many active compounds of medicinal plants are responsible for potential bio-activities. The treatment for ectoparasitic diseases in freshwater fish with formalin seems at present to be ineffective. For this reason, it is a useless cost. In addition, formalin possibly leaves toxic residues in the fish flesh and in the environment which are eventually harmful to consumers. The alternative way to solve this problem is to use a traditional medicinal plant. Trichodiniasis is one of the major diseases found in fish worldwide caused by protozoan parasites belonging to the phylum ciliophora.  The purpose of this research is to determine the possibility of using garlic (Allium sativum) as optional chemicals to treat fish ectoparasites, Tripartiella spp. The results showed that crude extracts of garlic at 550 mg/l significantly (P < 0.05) eliminated Tripartiella spp. infections in fingerlings of Labeo rohita (average weight 15 ±0.03 g each). To evaluate the acute toxicity of these products to the host fish, groups of 20 fingerlings (same size as above) were exposed to 3 concentrations of the product mentioned for 96 h. Mortality was then determined. The 2 h LC50 for fingerlings exposed to a crude extract of garlic was 2.125 mg/L. This information is beneficial and fundamental knowledge to develop guidelines to reduce the use of chemicals and antibiotics in freshwater fish culture businesses.