Preliminary assessment of the tolerance and efficacy of florfenicol against Edwardsiella ictaluri administered in feed to channel catfish

A tolerance study was conducted to determine the palatability of florfenicol to channel catfish Ictalurus punctatus. Four tanks of fish (20 fish/tank) were assigned to each of five treatments distinguished by the amount of florfenicol given in feed per kilogram of body weight, namely, 0, 10, 20, 40, or 100 mg. Fish were fed at a rate of 2.5% of body weight per day for 10 consecutive days. On day 11, all surviving fish were cuthanatized, counted, and weighed as a group. Florfenicol-medicated feed was palatable to fish at doses of 10, 20, 40, and 100 mg for 10 consecutive days.