Assessment of Biofilm Formation Potential among Multiple Drug Resistant Escherichia coli Strains with Potential to Produce Shiga Toxins Isolated from Various Chicken Meats

Escherichia coli is an important bacterial pathogen capable of multiple drug resistance and biofilm formation. Its presence in meats and their products may eventually lead to outbreaks especially if the pathogenic multidrug resistant strains are involved. The aim of this study was to determine the presence of Escherichia coli isolated from chicken meat samples in Gombe metropolis, their multidrug resistance as well as their potential to produce biofilms. A total of 60 chicken parts; 10 samples from each of chicken breast, drumstick, wings, thighs, backs and legs were purchased and analyzed. Specimens were immediately transferred to the laboratory in a cooler with an ice pack. The bacteriological culture-based technique on Eosin Methylene Blue (EMB) agar and Gram staining and further phenotypic identification techniques were employed to characterize the organism. Antimicrobial susceptibility testing using agar-disc diffusion was performed with 10 commonly used antibiotics using Mueller-Hinton agar. The incidence of E. coli was highest in the chicken legs with 33.3% (n= 10) and lowest in drumstick with 6.7% (n=02). The highest contamination level of E. coli was in chicken legs with 3.00 x 103 CFU/g while the lowest was observed in drumstick at 1.32 x 103 CFU/g. There was high resistance to Amoxycillin (100%), Tetracycline (100%), Doxycycline (93.3%), Mecillinam (90%) and Levofloxacin (70%). There was low resistance to Ciprofloxacin (10%), Streptomycin (10%), Ceftazidime (13.3%) and Ceftriaxone (16.7%). All the isolates except WEC 3 and LEC 10 were multidrug resistant. The multiple antibiotic resistance index (MARI) ranged from 0.3 to 0.7 indicating high risk of disease and eventually if not checked, can lead to outbreaks.