OCCURRENCE AND SENSITIVITY TO ANTIBIOTICS OF BACTERIA FOUND IN GILLS, BUCCAL CAVITY AND SKIN OF Hemichromis fasciatus, Brycinus macrolepidotus AND Hydrocynus forskalii FROM OGUN RIVER, ABEOKUTA, OGUN STATE

Abstract

The morphometrics of Hemichromis fasciatus, Brycinus macrolepidotus and Hydrocynus forskalii from Ogun River were determined. The culture, isolation, and characterization of  bacteria species, their sensitivity to antibiotics were carried out. There were significant differences (P>0.05) in the weight, standard length, head length, gill length and buccal depth. The highest mean body weight 113.85 ± 9.38 g was observed in B. macrolepidotus while the lowest mean weight of 47.20 ± 6.3 g was observed in H. forskalii. Ten (10) bacteria species were isolated from the gill, buccal cavity and skin. These include the Gram positive (Staphylococcus epidermidis, Streptococcus faecium, Micrococcus  letus) and the Gram negative bacteria (Enterobacter aerogenes, Pseudomonas aerogenes, Klebseilla aerogenes, Aerobacter  aerogenes, Proteus vulgaris, Bacillus licheniform and Salmonella sp). The number of colony forming units per milligram varied from 3.1×10⁴ to 3.8×10⁵. The highest mean percentage bacteria occurrence of 5.4 ± 4.4at (P> 0.05) was recorded from the gills of H. fasciatus while the lowest value of 4.6 ± 3.8was recorded in the gill of H. forskalii S. epidermidis had  the widest inhibition zones of 10.2 mm and 10.5 mm respectively of sensitivity to Sparfloxcin and Caflazidime while P. vulgaris had the thinnest inhibition zone 2.1 mm of resistance to Caflazidime. From the foregoing results, this study confirmed that the bacterial organisms isolated from the fish were pathogenic and of public health importance. Caflazidime and Oflaxacin were the best antibiotic substances with the highest inhibition zones of 10.5 mm and 10.0 mm for the Gram positive bacteria (S. epidermidis) and the Gram negative bacteria (E. aerogenes) respectively.