JOURNAL OF ANATOLIAN ENVIRONMENTAL AND ANIMAL SCIENCES, vol.5, no.4, pp.624-629, 2020 (Peer-Reviewed Journal)
Twelve Chryseobacterium piscicola isolates recovered from rainbow trout weighing
1-4 grams showing signs of anorexia, exophthalmos, darkening, and dorsal fin erosion were used
in our study. In addition to conventional microbiological tests, comprehensive phenotypic
characterization has been performed using the Biolog GENIII microplate. Molecular
identification and characterization were performed using the 16S rRNA region. Antimicrobial
susceptibilities of the isolates were determined using the Kirby-Bauer disk diffusion method. Our
isolates were identified as C. piscicola in molecular identification performed by sequence analysis
based on the 16S rRNA region. In a phylogenetic analysis of our isolates, obtained from three
different hosts in America, Chile, and Finland, five genogroups were determined with high
similarity rate. Isolates from Finland, Chile, the United States, and Turkey (only C-316) were
found in the same genogroup. It was determined that the phylogenetic analysis created with the
16S rRNA region could not distinguish the host from which the bacteria was isolated. The
phenotypic characterization of six representative isolates selected according to phylogenetic
analysis was determined with the Biolog GENIII microplate. Based on the Biolog GENIII results
of the representative isolates, the results of 40 out of 94 tests were found to be variable. With this
result, it was found that C. piscicola isolates were not phenotypically homogeneous. Besides, it
was found that the zone diameters of our isolates against florfenicol, enrofloxacin, and
sulfamethoxazole/trimethoprim