Oxytetracycline Hydrochloride (Dalimycin) is a tetracycline derivative produced by Streptomyces rimosus with antimicrobial activity. It interferes with the binding of aminoacyl-tRNA to the mRNA-ribosome complex, resulting in preventing peptide elongation and inhibiting protein synthesis.

The 10-day effect of oxytetracycline at therapeutic doses (82.8 mg/kg bw to 1 % bw/day) was species-specific. Oxytetracycline increases the enzymatic activity of CYP3A4 in Ictalurus punctatus, increases the protein expression of CYP3A4 in Oreochromis niloticus, and depletes hepatic CYP3A4 in the latter, and also increases the relative liver weight of Morone chrysops x M. saxatilis [1]. Oxytetracycline is limited to 100 μg/kg in muscle and breast milk, 200 μg/kg in eggs, 300 μg/kg in liver, and 600 μg/kg in kidney[3].