Four different sizes (1,10,150,300 gram body weight) of rainbow trout were separately subjected to various levels of freshly powdered clove tree with concentrations of 50,100, 150, 200, 250, 300, 350, 400, 450 and 500 ppm . Results showed that as the weight of fish increased a higher concentration of clove tree is needed for induction of anesthesia and LC50 raises. LC50 for fish weights of 1, 10, 150 and 300 grams were found to be 168, 153, 310 and 344 ppm , respectively.
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