Aerobic Oral and Nasal Bacteria in New Jersey Black Bears (Ursus americanus) with a Report on Antibiotic Susceptibility of Escherichia coli

Abstract

ABSTRACT The microbiology of animal bite wound infections is often polymicrobial. Black bear attacks have been a rare occurrence in the past and with few published studies on their oral flora, the bacteria present in black bear bite wounds is largely unknown. This study examines the oral and nasal aerobic bacteria from research trapped bears in northwestern New Jersey during June 2014. Oral swabs from the buccal and lingual supragingival tooth surfaces and nasal swabs from 22 black bears were plated onto Tryptic Soy Agar (TSA), Eosin Methylene Blue agar (EMB), and Columbia Nalidixic Acid agar (CNA) for bacterial isolation. Twelve aerobic bacterial species were identified from the oral and nasal samples. The most frequently isolated bacteria were Bacillus sp., Klebsiella oxytoca, Micrococcus luteus, Pseudomonas aeruginosa and Staphylococcus epidermidis. The diversity in the aerobic oral and nasal flora of black bears in New Jersey suggests the importance of including these organisms in basic health risk assessment protocols and suggests a potential tool for assessment of bear/habitat interactions. To evaluate the role of black bears in the spread of antibiotic resistant Escherichia coli, oral, nasal and anal samples were collected from eight black bears (two sows and six cubs). Antibiotic resistance was measured for tetracycline and streptomycin. E.coli resistance for tetracycline and streptomycin was 7%.