Accumulation and depletion of oxytetracycline in juvenile white shrimp (Penaeus setiferus)

Abstract

Oxytetracycline was fed in a formulated feed to juvenile white shrimp (Penaeus setiferus) at concentrations ranging from 1,000 to 10,000 mg/kg of feed for 3 weeks, followed by 2 weeks of feeding without oxytetracycline. Oxytetracycline was detectable after 24 h of feeding at 5,000 and 10,000 mg/kg of feed, and after 48 h when 1,000 mg/kg was fed. Peak concentrations at 5,000 and 10,000 mg oxytetracycline were reached within the first week of feeding in one group of shrimp while the other group required 2 weeks at 5,000 and 3 weeks at 10,000 mg oxytetracycline to reach maximum levels. At 1,000 mg oxytetracycline maximum retention occurred during the third week of feeding in both groups. When food containing oxytetracycline was discontinued, retention of this antibiotic in the shrimp was undetectable within 3 days for the 1,000 mg group and within 2 weeks for the groups on 5,000 and 10,000 mg/kg oxytetracycline diets. © 1979.