Gastrointestinal Microflora of Loggerhead Sea Turtles (Caretta caretta)

Podaci o mikroflori probavnog sustava glavate želve i antimikrobnoj rezistenciji su poprilicno oskudni. Gastrointestinalna mikroflora gmazova se primarno sastoji od aerobnih i anaerobnih gram negativnih i gram pozitivnih bakterija, gljivica i protozoa. Vecina izolata su opisani kao oportunisticki patogeni koji mogu izazvati bolest u imunokompromitiranih ljudi i životinja. Cilj ovog rada je bio bolji uvid u mikrofloru probavnog sustava glavate želve i rezistenciju bakterijskih izolata na antibiotike. Ove informacije mogu poslužiti u svrhu lijecenja i primjene antibiotika u ozlijedenih kornjaca na oporavku u centrima za rehabilitaciju morskih kornjaca, ali i kao bioindikator zagadenja morskog okruženja industrijskim i poljoprivrednim otpadom. Uzeti su obrisci usne šupljine i kloake 17 glavatih želvi iz Centra za oporavak morskih kornjaca Pula. Uzorci su analizirani u laboratoriju Zavoda za bolesti peradi s klinikom Veterinarskog fakulteta Sveucilišta u Zagrebu. Obrisci su nasadeni na neutralni i briljant zeleni agar, te inkubirani 24 sata na sobnoj temperaturi. Bakterije su identificirane bojanjem po Gramu, testom tvorbe katalaze i citokrom oksidaze te API biokemijskim testovima. Za dokaz gljivica uzorci su nasadeni na Sabouraudov agar i inkubirani 5 dana na sobnoj temperaturi. Osjetljivost prema antimikrobnim pripravcima odredena je disk difuzijskim postupkom (antibiogram). Izolirano je ukupno 12 razlicitih gram negativnih bakterija (S. putrefaciens, E. coli, P. fluorescens, P.vulgaris, A. hydrophila, P. aeruginosae, A. salmonicida, E. aerogenes, P. mirabilis, M. morganii, C. braaki i C. freundii), 5 gram pozitivnih (M. luteus, Micrococcus sp., S. contus, S. carnosus i Bacillus sp.) i 4 gljivice (Mucor sp., R. rubra, C. albicans i Cladosporium sp.). Bakterijski sojevi su pokazali raznoliku rezistentnost prema 11 antibiotika (gentamicin, enrofloksacin, ceftazidime, azitromicin, amoksicilin-klavulonska kiselina, lincomicin, tetraciklin, trimetroprim–sulfametoxsazol, ciprofloksacin, cefotaksim i amoksicilin). Najveca rezistentnost bila je na amoksicilin i linkomicin, a najmanja na gentamicin. Vecina izoliranih bakterija i gljivica predstavljaju normalnu mikrofloru morskog okruženja i probavnog sustava morskih kornjaca, no ipak mogu biti i potencijalni patogeni u životinja koje su ozlijedene ili pod stresom, te imunokompromitiranih ljudi.The information on normal gastrointestinal microflora in loggerhead sea turtle and antimicrobial resistance are quite scarce. Gastrointestinal microflora of reptiles consists primarily of aerobic and anaerobic gram positive and gram negative bacteria, fungi and protozoa. Most isolates are described as opportunistic pathogens that can cause disease in immunocompromised animals and humans. The aim of this study was to improve knowledge about microflora of the digestive system of loggerhead sea turtle and the resistance of bacterial isolates to antibiotics. This information can be used for better treatment of injured turtles in rehabilitation centers of sea turtles and also as bioindicator of pollution of the marine environment. The swabs were taken from oral cavity and cloaca of 17 loggerhead sea turtles from Pula rescue center. Samples were analyzed in the laboratory of the Department of Avian Diseases with Clinic on Faculty of Veterinary Medicine, University of Zagreb. Swabs were plated on Nutrient agar and Brilliant green agar and incubated for 24 hours at room temperature. The bacteria were identified by Gram staining, catalase and cytochrome oxidase tests and API biochemical tests. Samples for fungi identifications were plated on Sabouraud agar and incubated for 5 days at room temperature. Sensitivity to antimicrobial preparations was determined by disk diffusion method. A total of 12 different gram-negative bacteria (S. putrefaciens, E. coli, P. fluorescens, P. vulgaris, A. hydrophila, P. aeruginosae, A. salmonicida, E. aerogenes, P. mirabilis, M. morganii C. braaki and C. freundii), 5 gram positive (M. luteus, Micrococcus sp., S. contus, S. carnosus and Bacillus sp.) and 4 fungi (Mucor sp., R. rubra, C. albicans and Cladosporium sp.) were isolated from oral cavity and cloacal swabs. Bacterial strains showed a variety resistant to 11 antibiotics (gentamicin, enrofloxacin, ceftazidime, azithromycin, amoxicillin - clavulanate, lincomicin, tetracycline, trimethroprim-sulfametoxsazol, ciprofloxacin, cefotaxime and amoxicillin). The highest resistance was to amoxicillin and lincomicin, and the lowest to gentamicin. Most of the isolated bacteria and fungi are normal inhabitants of the marine environment and the gastrointestinal system of sea turtles. Someone of this isolates may be potential pathogens in animals that are injured or stressed, and immunocompromised humans