Few reptile population Salmonella prevalence studies have examined the association between positive culture and clinical disease.1,2 Salmonella culture results from captive reptiles at the Bronx Zoo were reviewed for a 13-year interval. In total, 175 samples from 182 individuals (n=4 samples from 11 crocodilians, n=91 samples from 78 snakes, n=57 samples from 59 lizards, n=23 samples from 34 chelonians) yielded 182 isolates. Serotype distribution differences were noted for sample type, family, and animal origin and health. Salmonella enterica subspecies enterica was most common (44.6%, 78/175) and found across all taxa, especially serotypes in the O:7 and O:8 antigen groups. Salmonella enterica subspecies diarizonae was common (24.0%, 42/175), and found almost exclusively in snakes (n=33), many with clinical illness (n=17). Where submission totals were recorded (2008–2012), snakes had highest antemortem prevalence (32.8%), with all positives from fecal samples (n=21). Clinically ill animals were the source of 35.2% Salmonella isolates (64/182). Bony changes (n=15), dermatitis (n=15), and anorexia (n=14) were the 3 most common clinical signs in these cases. Snakes (n=39/91) and turtles (n=10/23) with positive cultures had a higher likelihood of illness than lizards (n=13/57; p=0.01). Salmonella-positive ill animals were more likely to be confiscated in origin than from captive or commercial sources (p<0.01). Conclusions from this study can guide management of Salmonella-positive captive reptiles.
The authors appreciate the time spent collating this data by Jean Lay and Dr. Kimberly Rainwater, as well as the members of the Zoological Health Program’s Clinical and Pathology Departments and the Department of Herpetology for collection of samples and data used in this study. The authors also recognize the contributions of the Cornell University College of Veterinary Medicine Animal Health Diagnostic Center and Dr. Pat McDonough for sample testing and initial data compilation.
1. Onderka, D.K. and M.C. Finlayson. 1985. Salmonellae and salmonellosis in captive reptiles. Can. J. Comp. Med. 49:268–270.
2. Ramsay E.C., G.B. Daniel, B.W. Tyron, J. I. Merryman, P.J. Morris, and D.A. Bemis. 2002. Osteomyelitis associated with Salmonella enterica SS arizonae in a colony of ridgenose rattlesnakes (Crotalus willardi). J. Zoo. Wildl. Med. 33:301–310.