Cultivable Bacteria Associated with the Microbiota of Troglophile Bats

Background: The study of bats is of significant interest from a systematic, zoogeographic, ecological, and physiological point of view. The aim of this study is to investigate the culturable aerobic enteric, conjunctival, and oral bacterial flora of bats to determine their physiological microbiome and to investigate the possible occurrence of pathogenic bacteria. Methods: Five hundred and sixty-seven samples were collected from 189 individuals of four species of troglophile bats (Myotis myotis, Myotis capaccinii, Miniopterus schreibersii, and Rhinolophus hipposideros) living in Sicilian and Calabrian territory (Italy). All samples were tested for Gram-negative bacteria; conjunctival and oral swabs were also submitted to bacteriological examination for Gram-positive bacteria. Results: Four hundred thirteen Gram-negative strains were isolated. Of these, 377 belonged to 17 different genera of the family Enterobacteriaceae and 30 to five other families. One hundred eighty-three Gram-positive strains were isolated. Of these, 73 belonged to the Staphylococcaceae family, 72 to the Bacillaceae family and 36 to four other families. Besides some potentially pathogenic strains, several bacterial species have been found that are common to all the bat species studied. These could perhaps play a physiological or nutritional role. Conclusion: A great variety of bacterial species were identified in the cultivable microbiota of southern-Italian troglophile bats, including several potentially pathogenic strains and numerous putatively symbiotic species