Abstract:
Tetracycline (TET) has been extensively used in
aquaculture for chemotherapy against various fi sh diseases.
The contamination levels in 16 aquaculture farms in Sri Lanka
were analyzed using high performance liquid chromatography
(HPLC). The presence of antibiotic-resistant bacteria was
identified using the 16SrRNA gene sequencing and the
corresponding antibiotic resistant genes (ARGs) were screened
at each location using the PCR method. The concentration of
TET in the aquaculture farm samples ranged between 0.001±
0.001 - 0.112± 0.017 ppm. Bacillus and Staphylococcus were
recorded as the most dominant resistant bacterial genera against
TET. Acinetobacter sp., Achromabacter sp., Staphylococcus
sp., Micrococcus sp. were also identifi ed as resistant bacteria.
In the present study, tet (M) and tet (A) were the abundant
resistance genes (11/16 isolates), followed by tet (S) (5/16)
and tet (B) (4/16). It was found that tet (M) is one of the most
widely distributed tetracycline resistance determinants in the
aquacu lture environment in Sri Lanka.