Residue depletion of albendazole and its metabolites in the muscle tissue of large mouth and hybrid striped bass after oral administration

The residue depletion profiles of albendazole (ABZ) and its major metabolites: albendazole sulfoxide (ABZ-SO), albendazole sulfone (ABZ-SO₂) and albendazole aminosulfone (ABZ-2-NH₂SO₂) were studied in the muscle tissues of large mouth (LMB) and hybrid striped bass (HSB). A single oral dose of 10 mg/kg albendazole was given to the two fish species via intra-gastric tube. The muscle tissues with adhering skin were collected at 8, 16, 24, 48, 72, 96 and 120 h post dose from both species. The samples were homogenized in dry ice and subjected to extraction and cleanup procedures. The final sample extracts were analyzed by high performance liquid chromatography. The results indicate that both ABZ and its pharmacologically active metabolite ABZ-SO were retained longer in LMB than in HSB after oral treatment. Albendazole was detectable until 8 h or 6.7 degree days (°D) and 48 h (40 °D) in HSB and LMB, respectively. However, ABZ-SO was detectable up to 48 h (40 °D) and 96 h (80 °D) in HSB and LMB, respectively. Among the inactive metabolites, ABZ-SO₂ was present in both fish species; however, ABZ-2-NH₂SO₂ was detected only in LMB.