26th Annual Meeting and Symposium of the
Desert Tortoise Council, March 16-18, 2001
Abstracts

STUDENT PAPER

Serologic and PCR Findings on Captive Desert Tortoises in the Greater Barstow Community, California for Exposure to Mycoplasma and Herpesvirus

April Johnson¹, David J. Morafka², Elliott Jacobson³, Lori Wendland³, and Francesco Origgi^3
1College of Veterinary Medicine, University of Illinois, Urbana, Illinois 61802
²California State University, Dominguez Hills, Carson, California 90747
³College of Veterinary Medicine, University of Florida, Gainesville, Florida 32610

Mycoplasma agassizii and herpesvirus are known to cause respiratory disease in tortoises. Clinical signs of both diseases may be similar, including nasal discharge and conjunctivitis. Escaped or released infected captive desert tortoises (Gopherus agassizii) pose a potential threat of disease introduction to healthy wild populations. One hundred sixty-two captive desert tortoises from Barstow, California and surrounding towns were tested for evidence of previous exposure to these two infectious agents. Access to these captives was facilitated by the local (High Desert) chapter and members of the California Turtle and Tortoise Clubs (CTTC) and the cooperation of a local veterinarian (Dr. T. R. Rao), who made his hospital available for our examinations. Blood samples were collected from July 19 through August 17, 2000, for enzyme linked immunosorbent assay (ELISA) testing to detect antibodies specific for exposure to M. agassizii and herpesvirus. At the same time, nasal flush samples were collected from 69 tortoises for PCR testing to detect M. agassizii antigen. The results showed that, of the 162 ELISA assays, 130 were positive for M. agassizii antibodies, 10 were suspect, and 22 were negative. All 69 PCR assays for M. agassizii antigen were negative, of which 53 were positive on ELISA assay, 1 was suspect, and 15 were negative. Of 40 ELISAs performed to detect herpesvirus antibody, 12 were positive. Further work is needed to determine the risk of release of seropositive tortoises into susceptible wild populations.