Salmonella serovars and antimicrobial resistance in strains isolated from wild animals in captivity in Sinaloa, Mexico.

The aim of the present study was to evaluate the frequency of antibiotic resistance in Salmonella spp. strains from wild animals in captivity at the Culiacan Zoo and the Mazatlan Aquarium in Sinaloa, Mexico. We identified 17 different Salmonella enterica serovars at a prevalence of 19.90% (Culiacan Zoo) and 6.25% (Mazatlan Aquarium). Antibiotic sensitivity tests revealed that, of the 83 strains studied, 100% were multidrug resistant (MDR). The drugs against which the greatest resistance was observed were: penicillin, erythromycin, dicloxacillin, ampicillin, cephalothin, and chloramphenicol. We therefore conclude that MDR is common among Salmonella isolates originating from wild animals in captivity in Sinaloa.

Prevalence of Salmonella enterica serovar Albany in captive zoo wild animals in the Culiacán Zoo in Mexico.

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 Culiacán 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.

Excreción fecal de Salmonella Albany, su aislamiento en la ración alimenticia y repercusión en el estado de salud de un ocelote (Leopardus pardalis) en cautiverio / Fecal excretion of Salmonella Albany, its isolation in the diet and health repercussion on an ocelot (Leopardus pardalis) in captivity

Salmonella enterica serotypes are 99% responsible for salmonellosis in human and animals, especially Salmonella enterica serovar Albany that has been identified in chicken carcass representing a risk for human and animal health. Salmonella enterica serovar Albany was isolated from the feces of a male ocelot (Leopardus pardalis), at the zoo in Culiacan, Sinaloa, Mexico, and from raw chicken (feline's diet). The pulsed-field gel electrophoresis pattern (PFGE) generated by Xba I enzyme was identical in both isolates, indicating that the source of infection was the raw chicken. Five months after having isolated the bacteria from the feces, a post mortem study was carried out on the feline. Macroscopically, severe hemorrhagic enterocolitis and renal fibrosis was observed and microscopically, there was evidence of severe mononuclear lymphocytic infiltration in the ileum, as well as necrosis of intestinal villi and crypts, besides severe multifocal interstitial nephritis and fibrosis in both kidneys. The invA gene was amplified from intestinal samples confirming an infection by Salmonella. The microbiologic, molecular and histopathology diagnoses suggest that death of the feline was caused by ingestion of raw chicken contaminated with Salmonella enterica serovar Albany. This clinical case highlights the importance of persistent fecal Salmonella shedding animals and describes the molecular epidemiological relationships of isolates from feces and food, which allowed to find the primary source of infection.

Los serotipos de Salmonella especie enterica son los responsables del 99% de las salmonelosis en humanos y animales, en particular, Salmonella enterica serovariedad Albany se ha identificado en canales de pollo, por lo que representa un riesgo para la salud humana y animal. Se aisló Salmonella enterica serovariedad Albany a partir de heces de un ocelote macho (Leopardus pardalis), cautivo en el zoológico de Culiacán, Sinaloa, México, y de pollo crudo (alimento del felino). El patrón por electroforesis en campo pulsado (PFGE) con la enzima Xba I fue idéntico en ambos aislados, lo que indica que la fuente de infección fue el pollo crudo. Cinco meses después de haber aislado las bacterias de las heces, se realizó estudio post mortem del felino anteriormente mencionado, y se observó macroscópicamente: enterocolitis hemorrágica severa y fibrosis renal; y microscópicamente: necrosis de vellosidades y de criptas e infiltrado mononuclear linfocitario severo en íleon, además nefritis intersticial severa multifocal y fibrosis en riñón. A partir de muestras intestinales se amplificó el gen invA que confirma la infección por Salmonella. Los diagnósticos microbiológico, molecular e histopatológico sugieren que la muerte del felino se debió a la infección causada por la ingesta de pollo crudo contaminado con Salmonella enterica serovariedad Albany. Este caso clínico confirma la importancia que tienen los animales que excretan Salmonella vía fecal y describe la relación epidemiológica-molecular de los aislamientos obtenidos de heces y alimento, lo que permitió esclarecer la fuente primaria de infección.