Histopathology and Antibiotic Susceptibility of Aeromonas hydrophila Isolated from Diseased Guppy (Poecilia reticulata)

Abstract

This study was carried out to determine the reason of mortality in guppy (Poecilia reticulata) kept in an aquarium fish-rearing farm in Istanbul province and confirm damage caused in tissues and antibiotic susceptibility of isolated pathogen bacteria. Externally diseased guppies (n=15) showed sloughing scales, ulcerative skin lesions on the body surface and abdominal distension; internally pale liver and accumulation of a liquid in the abdominal cavity were observed. Bacteriological inoculation from internal organs such as liver, spleen and kidney of guppies (n=15) were made onto Tryptic Soy Agar (TSA) and Brain Heart Infusion Agar (BHIA). After incubation, all isolated bacteria were identified as Aeromonas hydrophila according to their psychological, morphological, biochemical characteristic, and API 20E profile. Also, these isolates (n=15) were determined to be sensitive to chloramphenicol and florfenicol. Histopathologically, multifocal liquefactive necrosis in the spleen, liver, kidney and heart, degeneration of tubular epithelium and necrosis in the kidney, desquamation of mucosa epithelium and necrotic gastric glands in the stomach, discharge of the white pulp in the spleen, desquamation of the lamina propria and mucosa epithelium in the intestine, and sloughed off the necrotic gill epithelium cells were observed.