Health Assessment of Free-Ranging Hoffmann’s Two-Toed (Choloepus hoffmanni) and Brown-Throated Three-Toed (Bradypus variegatus) Sloths in Costa Rica
American Association of Zoo Veterinarians Conference 2006
Joanna Siudak-Campfield1,2, MS; Christopher S. Hanley1,2, DVM; Joanne Paul-Murphy1,2, DVM, DACZM; Christopher Vaughan3, PhD; Oscar Ramirez4, MS; Eleanor Deadroff5, BA; Amelia Travassos da Rosa5, BS; Scott C. Weaver5, PhD; Kurt K. Sladky1,2, MS, DVM, DACZM
1Special Species Health Service, Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA; 2Conservation Health Consortium, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA; 3Department of Wildlife Ecology, University of Wisconsin, Madison, WI, USA; 4International Institute for Wildlife Conservation and Management, Universidad National, Heredia, Costa Rica; 5Center for Biodefense and Emerging Infectious Diseases and Department of Pathology, Medical Branch, University of Texas, Galveston, TX, USA
Abstract
During a ten-day period in August 2005, free-ranging Hoffmann’s two-toed sloths (Choloepus hoffmanni) (n=29) and brown-throated three-toed sloths (Bradypus variegatus) (n=20) were manually captured and immobilized using intramuscular ketamine (2.5 mg/kg) and medetomidine (0.02 mg/kg). Sloths were physically examined and blood samples collected for serum biochemical analysis and hematology. Remaining serum was stored frozen and tested at a later date for presence of arboviral antibodies at the Center for Biodefense and Emerging Infectious Diseases.
All individuals in this study appeared healthy based on routine physical examinations. Hematologic parameters and serum biochemical analysis were compiled into reference ranges for both species. Results were compared between species and genders by the Kruskal-Wallis test for non-parametric data, and analysis of variance (ANOVA) for parametric data. Serum albumin, globulin, blood urea nitrogen, alanine aminotransferase, total white blood cell count, absolute segmented neutrophil, lymphocyte, and basophil counts were significantly higher in Choloepus compared to Bradypus. Alternatively, serum glucose, creatinine, total calcium, and aspartate aminotransferase were significantly higher in Bradypus. No gender differences were observed.
Serum samples (n=45) were tested against Mayaro, Murutucu, Oropouche, Utinga, Munguba, Venezuelan equine encephalitis, St. Louis encephalitis (SLEV), and Ilheus (ILHV) viral antigens using the hemaglutination inhibition (HI) assay and against La Crosse, Punta Toro, Piry and Changuinola (CGLV) viral antigens using the complement fixation assay (CF). Seventy-one percent of the serum samples (32/45) were SLEV antibody positive, confirmed by plaque reduction neutralization test (PRN), and exact titers were determined. Fifty-five percent of the sera (23/45) were antibody-positive to both SLEV and ILHV viral antigens. Thirty-one percent of the sera (14/45) were antibody-positive to CGLV antigen. None of the samples were positive for West Nile virus specific antibodies.