• Early 1900s Detection of Batrachochytrium dendrobatidis in Korean Amphibians

      Fong, Jonathan J.; Cheng, Tina L.; Bataille, Arnaud; Pessier, Allan P.; Waldman, Bruce; Vredenburg, Vance T. (2015)
      The pathogenic fungus Batrachochytrium dendrobatidis (Bd) is a major conservation concern because of its role in decimating amphibian populations worldwide. We used quantitative PCR to screen 244 museum specimens from the Korean Peninsula, collected between 1911 and 2004, for the presence of Bd to gain insight into its history in Asia. Three specimens of Rugosa emeljanovi (previously Rana or Glandirana rugosa), collected in 1911 from Wonsan, North Korea, tested positive for Bd. Histology of these positive specimens revealed mild hyperkeratosis – a non-specific host response commonly found in Bd-infected frogs – but no Bd zoospores or zoosporangia. Our results indicate that Bd was present in Korea more than 100 years ago, consistent with hypotheses suggesting that Korean amphibians may be infected by endemic Asian Bd strains.
    • Histopathologic findings in free-ranging California hummingbirds, 1996–2017

      Magagna, Michelle; Noland, Erica; Tell, Lisa A.; Purdin, Guthrum; Rideout, Bruce; Lipman, Max W.; Agnew, Dalen (2018)
      A histopathologic study of free-ranging hummingbirds in California was performed to identify mortality trends. Tissues from 61 wild hummingbirds representing five native California species collected by the San Diego Zoo from 1996 to 2016 or the Lindsay Wildlife Experience from 2015 to 2017 were histologically examined....
    • Low MHC variation in the polar bear: Implications in the face of Arctic warming?

      Weber, D.S.; Van Coeverden de Groot, P.J.; Schrenzel, Mark D.; Perez, D.A.; Thomas, S. (2013)
      Animals in the Arctic have low pathogen diversity but with rapid climate warming, this is expected to change. One insidious consequence of climate change is exposure of Arctic species to new pathogens derived from more southern species expanding their range northward. To assess potential vulnerability of polar bears to disease exposure, we examined genetic variation in major histocompatibility complex (MHC) loci (part of immune system) in Canadian polar bears and found low genetic diversity, consistent with long?standing exposure to low pathogen/parasite loads....
    • Proximate causes of the red face of the bald uakari monkey (Cacajao calvus)

      Mayor, P.; Mamani, J.; Montes, D.; González-Crespo, C.; Sebastián, M. A.; Bowler, Mark (2015)
      In social species, such as primates, facial appearances transmit a variety of social signals. Although it is suggested that the intense red colour of the face of the bald uakari monkey might be an indicator of health, this hypothesis still has not been verified. This study describes the histological structure of the skin of the face in the bald uakari, compared with other non-red neotropical primates, to better understand the maintenance of its colour. The facial skin of the bald uakari monkey is characterized by a thinner epidermis, absence of melanin pigments and a high density of vascular capillaries that spread below the epidermis. These vascular capillaries are larger and more tortuous than in other neotropical primates. The skin of the face of the bald uakari monkey allows a direct external assessment of haematological status, suggesting that the colour of the face would be an honest indicator of health, but could also signal sexual or behavioural states.
    • Pulmonary hyalinosis in captive sugar gliders (Petaurus breviceps)

      Sokol, Set A.; Agnew, Dalen W.; Lewis, Anne D.; Southard, Teresa L.; Miller, Andrew D. (2017)
      ...Lung lesions resembling pulmonary hyalinosis were observed in 6 captive adult sugar gliders (Petaurus breviceps; 5 females and 1 male) in a retrospective review of 18 autopsied animals. Clinical signs for 3 of the sugar gliders included lethargy, tachypnea, and dyspnea....