Antimicrobial Resistance Profile of Aerobic Nasal Microflora of Nigerian Indigenous Pigs

There is increasing global threat of antimicrobial resistance (AMR) mostly with regards to the exchange of potentially harmful microbes across human and animal populations. There is also limited information in literature on the microbial population of Nigerian Indigenous Pigs (NIP). This study was designed as a preliminary investigation to provide baseline information on the AMR profile of nasal flora of NIP. Thirty-one nasal swabs were collected from NIPs on the Teaching and Research Farm, University of Ibadan, Nigeria. Bacteria were isolated, characterized and identified using cultural and biochemical characteristics. Antibiotic Susceptibility Testing (AST) was carried out on the pure strains of bacteria using the gram positive and negative antibiotic sensitivity discs. Three media were used for isolation; Nutrient agar, MacConkey agar and Mannitol Salt Agar. Data were analysed using descriptive statistics. Ten multi-drug resistant bacteria were identified; Staphylococcus aureus (96.8%), Escherichia coli (87.1%), Shigella species (80.6%), Bacillus species 51.6% (16/31) and Serratia species 51.6% (16/31) were the most frequently isolated. Of the isolated organisms, the gram positive organisms showed high resistance to Ceftazidime (81.1%), Ceftriaxone (86.9%), Cloxacilin (93.4%), Augmentin (100%), and Cefuroxime (100%) with considerable sensitivity to Ofloxacin (74.6%) and Gentamicin (80.9%). While the gram negative bacteria were highly resistant to Tetracycline (77.6%), Cefuroxime (90%), Ceftriaxone (87.1%), Sulbactarm (83.2%) and Ampiclox (85.7%) with considerable sensitivity to Levofloxacin (78.9%) and Nitrofurantoin (93.4%). This study reveals a high microbial load of AMR bacteria in the nasal cavity of NIPs making them a possible reservoir. These findings unveil the need for genetic data to determine the pattern, extent and basis of AMR resistance in the nasal flora of NIPs. We therefore recommend more rational use of antibiotics in pigs and other food animals to safeguard animal and human health.