Abstract:
The study sought to investigate antibiotic resistant bacteria from fish farms in
the Central and Western regions of Ghana. Management practices and
antibiotic use at the fish farms were obtained through questionnaire. Bacterial
loads of catfish (Clarias gariepinus), tilapia (Oreochromis niloticus), and
pond water samples recovered on MacConkey Agar and Mannitol Salt Agar
were determined. Bacterial isolates were identified using biochemical assays.
Antibiotic resistance profile and resistant genes of isolates were determined
using disc diffusion method and Polymerase Chain Reaction technique
respectively. The study revealed that none of the selected farms made use of
antibiotics for prevention and treatment of diseases and no major disease
outbreak had ever been recorded. Bacterial loads of pond water and fish
samples exceeded the acceptable level of ≤100 E. coli and <10 coliforms per
mL for wastewater recommended for use in fish farming and 5×105CFU/g for
fresh fish regarded as wholesome. Total of 145 bacterial isolates consisting of
99 (68.30%) coliforms and 46 (31.70%) Gram-positive bacteria were obtained.
All isolates showed resistance to at least an antibiotic except Edwardsiella
tarda. Both coliform and Gram-positive bacteria were highly resistant to betalactams
with corresponding high detection of TEM gene compared to other
classes of antibiotics. This study has demonstrated that antibiotic resistant
bacteria are present at the fish farms and might have been introduced into the
fish farms from the environment where antibiotics are regularly used.
Education on risks associated with the use of antibiotics and its impact on
bacteria in the environment needs to be intensified.
