Salmonellosis in Stranded and Pelagic Olive Ridley Turtles (Lepidochelys olivacea) in the Pacific
American Association of Zoo Veterinarians Conference 2019
Terry M. Norton1,2, DVM, DACZM; Thierry M. Work3; Julie Dagenais3; Brian A. Stacy4; Jason T. Ladner5; Jeffrey M. Lorch6; Thomas Waltzek7; George H. Balazs8; Brenda M. Berlowski-Zier6; Renee Breeden3; Elías Barquero-Calvo9; Isabel Contreras10; Natalia Corrales Gomez11; Rocío González-Barrientos12; Heather S. Harris13; Ángel Herrera-Ulloa11; Gabriela Hernández-Mora14; Shoreh Hesami15; T. Todd Jones6; Juan Alberto Morales9; Carlos Mario Orrego15; Robert A. Rameyer3; Daniel R. Taylor6
1Georgia Sea Turtle Center, Jekyll Island Authority, Jekyll Island, GA, USA; 2Turtle Hospital, Marathon, FL, USA; 3U.S. Geological Survey, National Wildlife Health Center, Honolulu Field Station, Honolulu, HI, USA; 4NOAA Fisheries, Office of Protected Resources, University of Florida, Gainesville, FL, USA; 5The Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, USA; 6U.S. Geological Survey, National Wildlife Health Center, Madison, WI, USA; 7Department of Infectious Diseases and Immunology, University of Florida, Gainesville, FL, USA; 8NOAA, National Marine Fisheries Service, Marine Turtle Program, Honolulu, HI, USA; 9Escuela de Medicina Veterinaria (EMV), Universidad Nacional Costa Rica, Costa Rica; 10Fundacion Zoologica de El Salvador, Antiguo Cuscaltán, La Libertad, El Salvador; 11Parque Marino del Pacífico-Universidad Nacional Costa Rica, Costa Rica; 12Pathology Area National Service of Animal Health (SENASA), Ministry of Agriculture and Livestock, Costa Rica, California Department of Fish and Wildlife, Office of Spill Prevention and Response; 13Marine Wildlife Veterinary Care and Research Center, Santa Cruz, CA, USA; 14Bacteriology Area, National Service of Animal Health (SENASA), Ministry of Agriculture and Livestock, Costa Rica; 15Costa Rican Ministry of Environment and Energy, San Jose, Costa Rica
Salmonella spp. are frequently shed by wildlife including turtles, but S. enterica subsp. enterica serovar Typhimurium is rare in the latter. Moreover, the presence of lesions associated with Salmonella is unusual in chelonians. Using necropsy, immunohistochemistry, PCR, and culture, we showed that 11% of apparently healthy pelagic and 57% of stranded olive ridley turtles (Lepidochelys olivacea) on the Pacific coast of Central America, the continental United States, and Hawaii had renal granulomas associated with S. enterica ser. Typhimurium. The extent of renal lesions ranged from mild, focal granulomas to severe nephritis. Some animals were found during mass mortality events in Central America, suggesting that salmonellosis may have been a contributing cause. S. enterica ser. Typhimurium was the only species of Salmonella detected in olive ridley turtles, and phylogenetic analyses from whole-genome sequencing data showed that the isolates from olive ridley turtles formed a single clade distinct from other strains of S. enterica ser. Typhimurium. Although S. enterica ser. Typhimurium is known in coastal environments, its presence in olive ridley turtles within the oceanic environment is unexpected. Further study is warranted to determine the origin and host specificity of the olive ridley turtles S. enterica ser. Typhimurium strain as well as the potential role of salmonellosis in olive ridley turtle conservation. In addition, S. enterica ser. Typhimurium is one of the more common non-typhoidal Salmonella in humans, and olive ridley eggs are commonly harvested for human consumption in Central America, thus a potential for human exposure exists.