The incidence and antimicrobial susceptibility of Salmonella species isolated from captive reptiles at Ljubljana Zoo

Abstract

Cloacal swabs from 74 healthy reptiles at Ljubljana Zoo were examined for the presence of salmonellae. Thirty nine reptiles underwent at least one antimicrobial treatment 24 - 48 months before sample collection. The identification of salmonellae was performed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry and positive strains were serotyped. Salmonellae were found in 29.7% of all reptiles investigated, in 55.6% of reptiles kept with regularly direct contact with zoo visitors, and in 26.2% of reptiles kept strictly in terraria. The isolation prevalence was 38.6%, 18.2% and 12.5% in snakes, lizards and chelonians, respectively. Salmonella enterica subspecies enterica was the most common (63.6%) followed by subspecies diarizone (31.8%) and subspecies arizonae (4.5%). The serotypes Infantis and Uzaramo were detected in 27.3% and 36.4% of Salmonella positive samples, respectively. Resistance to antimicrobial agents was found in 9% of strains. A high percentage (63.6%) of Salmonella positive reptiles at Ljubljana Zoo shed serotypes that are known to be causative agents of human salmonellosis. This is the first documented isolation of serotype 57:k:e,n,x,z15 from captive reptiles.