Journal of Zoo and Wildlife Medicine 44(1): 8–14, 2013 Copyright 2013 by American Association of Zoo Veterinarians PREVALENCE OF SALMONELLA ENTERICA SEROVAR ALBANY IN CAPTIVE ZOO WILD ANIMALS IN THE CULIACA ´ N ZOO IN MEXICO Gabriela Silva-Hidalgo, D.V.M., M.S., He ´ctor Samuel Lo ´ pez-Moreno, Ph.D., Vianney Francisco Ortiz-Navarrete, M.S., Ph.D., Celia Alpuche-Aranda, M.D., Ph.D., Jose ´ Guadalupe Rendo ´n- Maldonado, M.S., Ph.D., Jose ´ Angel Lo ´pez-Valenzuela, M.S., Ph.D., Martin Lo ´ pez-Valenzuela, D.V.M., M.S., and Felipe Jua ´rez-Barranco, M.S., Ph.D. Abstract: Salmonellosis is an important zoonotic disease but little is known about the role that free-living animals play as carriers of this pathogen. Moreover, the primary route of infection in the wild needs to be elucidated. The aim of this study was to determine the source and the route of transmission of Salmonella enterica serovar Albany (S. Albany) infection in captive zoo wild animals in the Culiaca ´n Zoo. A total of 267 samples were analyzed including 220 fecal samples from zoo animals, 15 fecal samples from rodents, 5 pooled samples each of two insects (Musca domestica and Periplaneta americana), and 22 samples of animal feed. We detected S. Albany in 28 (10.5%) of the samples analyzed, including in samples from raw chicken meat. Characterization of isolates was performed by serotyping and pulsed-field gel electrophoresis. All isolates shared a single pulsed-field gel electrophoresis profile, indicating a possible common origin. These data suggest that the infected meat consumed by the wild felines was the primary source of infection in this zoo. It is likely that the pathogen was shed in the feces and disseminated by insects and rats to other locations in the zoo. Key words: Albany, carriers, feces, insects, Salmonella, wild animals, zoo. INTRODUCTION The genus Salmonella, which belongs to the family Enterobacteriaceae, is classified into two species, Salmonella enterica and Salmonella bongori (formerly S. enterica serotype V). More than 2,500 serovars of S. enterica are currently recognized based on O and H antigen typing. 13 Salmonella enterica serovars have been isolated from numer- ous species of free-living and captive mammals, with many studies focusing on agricultural animals and avian populations. Recent attention has turned to wildlife populations, but they are difficult to assess, making sampling for epidemiologic studies a challenge. 35 For this reason, the prevalence of Salmonella in wild populations is largely unknown. Many domestic and wild animals colonized by Salmonella harbor the bacteria in their gastrointes- tinal tracts with no apparent signs of illness. 33 Hence, Salmonella spp. may be present in feces excreted by healthy animals and can persist in the environment until they encounter conditions suit- able for growth; the persistence of Salmonella spp. and serovars in the environment is an important characteristic in their epidemiology. 40 In modern zoos, animals are kept in natural- looking environmental surroundings and animals, including nonpoisonous reptiles and mammals, are often allowed to roam freely in exhibits. There may be no fences so that visitors can touch the animals; this allows the possibility of contact with animal feces or contaminated surfaces. Indeed, many events at zoos are designed to allow visitors to come in close contact with the animals. In addition to direct transmission via animals to humans, Salmonella, which is relatively resistant to the environment, can be indirectly transmitted to humans through contact with a contaminated exhibit. 16 Outbreaks of salmonellosis in humans have been associated with contact with animals. In 1996, an outbreak occurred among individuals who attend- ed a lizard exhibit at the Denver Zoo (Colorado, From the Programa Regional del Noroeste para el Doctorado en Biotecnologı´a, Facultad de Ciencias Quı´- mico-Biolo´ gicas, Ciudad Universitaria, Av. Americas S/ N, Universidad Auto´ noma de Sinaloa, Culiaca´n, Sinaloa, 80010, Me´xico (Silva-Hidalgo, Lo´ pez-Moreno, Rendo´n- Maldonado, J. A. Lo´ pez-Valenzuela). Present addresses (Silva-Hidalgo): Rio Mocorito 140-A ote. Col. Guada- lupe, Culiaca´ n, Sinaloa, 80220, Me´ xico; (Ortiz-Navar- rete): Departamento de Biomedicina Molecular, Centro de Investigacio´ n y de Estudios Avanzados (CINVES- TAV), Instituto Polite´ cnico Nacional, Av. Instituto Polite´ cnico Nacional No. 2508, Col. San Pedro Zacaten- co, 07360 Me´ xico, D.F., Me´ xico; (Alpuche-Aranda): Instituto de Diagno´stico y Referencia Epidemiolo´gicos (InDRE), Carpio No. 470 Col. Santo Tomas, 11340 Me´xico, D.F., Me´xico; (Jua´ rez-Barranco, Lo´ pez-Valen- zuela): Laboratorio de Patologı´a, Facultad de Medicina Veterinaria y Zootecnia, Universidad Auto´noma de Sinaloa, Boulevard San Angel s/n, Fracc. San Benito, CP 80246, Culiaca´ n, Sinaloa, Me´xico. Correspondence should be directed to Dr. Silva-Hidalgo (gaby@uas. uasnet.mx or gabsilhid@uas.edu.mx). 8