Preliminary studies on the palatability, animal safety, and tissue residues of sarafloxacin-HCl in the penaeid shrimp, Penaeus vannamei

The palatability and animal safety (toxicity) during, and whole body tissue residues following, 15 days of medicated feeding of sarafloxacin-HCl (SAR) (Abbott Laboratories, North Chicago, IL) were evaluated in the penaeid shrimp, Penaeus vannamei, at doses of 1 × (200 mg SAR/kg of feed), 5×, 10×, and 50×. A significant reduction (P≤0.05) in SAR medicated feed palatability was noted with increasing dose rate. However, differences were not unacceptable, with approximately 92% of the feed being consumed in the 1× and 5× treatments and 82% in the 50× treatment, relative to the control diet. Lower weight gains were also noted in higher dose groups; however, these differences were not significant (P≤0.05). No significant differences (P≤0.05) in mortalities or signs of morbidity were noted in any of the treatments. However, feed conversion ratio's (FCR) showed a marked increase at dose levels 5×, 10× and 50×, possibly indicating subchronic toxicity. The elimination of SAR from shrimp tissue was rapid, with SAR tissue t _{1 2} being approximately 13.4 h. SAR tissue levels were below detectable limits by day 3, 7, 7, and 14 days post medicated feeding in the 1×, 5×, 10×, and 50× treatments, respectively. Peak tissue levels indicated a standard dose response in the 1×, 5×, and 10× treatments. Based on the results of this study and the common shrimp farming practice of feeding 2-3 or more times per day, a dose level less than the 1× used in this study may provide a therapeutic dose.