• A reservoir species for the emerging amphibian pathogen Batrachochytrium dendrobatidis thrives in a landscape decimated by disease.

      Reeder, N.M.M.; Pessier, Allan P.; Vredenburg, V.T. (2012)
      Chytridiomycosis, a disease caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), is driving amphibian declines and extinctions in protected areas globally. The introduction of invasive reservoir species has been implicated in the spread of Bd but does not explain the appearance of the pathogen in remote protected areas. In the high elevation (>1500 m) Sierra Nevada of California, the native Pacific chorus frog, Pseudacris regilla, appears unaffected by chytridiomycosis while sympatric species experience catastrophic declines. We investigated whether P. regilla is a reservoir of Bd by comparing habitat occupancy before and after a major Bd outbreak and measuring infection in P. regilla in the field, monitoring susceptibility of P. regilla to Bd in the laboratory, examining tissues with histology to determine patterns of infection, and using an innovative soak technique to determine individual output of Bd zoospores in water. Pseudacris regilla persists at 100% of sites where a sympatric species has been extirpated from 72% in synchrony with a wave of Bd. In the laboratory, P. regilla carried loads of Bd as much as an order of magnitude higher than loads found lethal to sympatric species. Histology shows heavy Bd infection in patchy areas next to normal skin, a possible mechanism for tolerance. The soak technique was 77.8% effective at detecting Bd in water and showed an average output of 68 zoospores per minute per individual. The results of this study suggest P. regilla should act as a Bd reservoir and provide evidence of a tolerance mechanism in a reservoir species....
    • Depositional diseases

      Graham, E.A.; Burns, Rachel E.; Ossiboff, R. J.; Garner, Michael M.; Jacobson, Elliott R. (CRC Press, 2021)
      This book accompanies Infectious Diseases and Pathology of Reptiles, Second Edition to cover noninfectious diseases of reptiles, meeting the need for a similar, authoritative single-source reference. The volume features color photos of normal anatomy and histology, as well as gross, light, and electron microscopic imagery of diseases. Subjects range from neoplasia, nutrition, and metabolic disease, and deposition disorders to developmental anomalies, trauma, and physical diseases, and the unique contribution of paleopathology and diseases of bone. Each chapter is supported by numerous figures, many of which are unique and cannot be found in the published literature. Readers will note that some of the chapters are based on organ system, a trend that will continue into the next edition to encompass all of the basic organ systems. This book holds the most information ever accrued into one publication on noninfectious diseases and pathology of this class of animals, providing information on every aspect of the anatomy, pathophysiology, and differential diagnosis. With up-to-the-minute data, a never-before-seen collection of images, and a stellar panel of contributors, Noninfectious Diseases and Pathology of Reptiles is the definitive resource for veterinarians, biologists, and researchers involved in the study of reptile diseases.