Antibiotic resistance - A comparison between biofilm and free cells of Escherichia coli and Staphylococcus aureus from canine pyometra

Biofilm cells of Escherichia coli and Staphylococcus aureus grown on chitin flakes (inert surface) and their planktonic cells (free cells) grown in tr yptic soya broth were exposed to gentamicin (8 mg/ml) and ciprofloxacin (0. 48 mg/ml) respectively. The viable counts of 1-, 3- and 5-day-old cells exp osed to antibiotics revealed that, the viable counts of biofilm cells were greater than planktonic cells. These observations indicated that growth wit hin thick adherent biofilm confers antibiotic resistance on cells of bacter ia.