Microbial resistance to antibiotics and biofilm formation ability of food-borne pathogens are major global health challenges. Most milk and milk products (Madara and Nono) could be vehicles for the transmission of multidrug resistant genes among any community. This study was aimed at determining the antibiotic susceptibility patterns and biofilm forming ability of some food-borne pathogens isolated from common dairy products: Madara and Nono in Makurdi metropolis. Two hundred and forty (240) samples comprising of one hundred and twenty (120) each of Madara (fresh raw milk from cow “FRM”)) and Nono (chance fermented cow milk “CFM”) were examined for the presence of pathogens. Antibiogram of bacterial isolates (Staphylococcus aureus, Escherichia coli, Shigella spp., Salmonella spp. and Klebsiella spp.) using the disc diffusion method revealed that susceptibility for Ampicillin (86.9%), Streptomycin (83.9%) and Ciprofloxacin (75.0%). Resistance was shown (26.7%) to Nalidixic acid, a commonly used antibiotic reflecting a public health concern. Most resistant isolates had a multiple antibiotics index of 0.3 (27.54%) with a least multiple antibiotics resistance index of 0.6 (0.85%). Detection of biofilm formation of isolates was done by Tube method. The study also revealed that out the total of 236 isolates tested for biofilm formation, 67 (28.4%) isolates were non or weak biofilm producers, 77 (32.6%) isolates were moderate biofilm producers and 92 (39%) isolates were strong biofilm producers. Findings of this research show high presence of a wide range of microorganisms, particularly enteric pathogens and enterotoxigenic strains of S. aureus which portrayed multidrug resistance and biofilm formation suggesting that FRM (Madara) and CRM (Nono) products might be important sources of food-borne infections and intoxication.
Psychrotrophic bacteria in Brazilian organic dairy products: identification, production of deteriorating enzymes and biofilm formation
