wildlife and zoo assay data sheet
F0005 - Ultrasensitive qualitative detection of
Batrachochytrium dendrobatidis by real time PCR
included in P0031 -
amphibian screening panel
In the past,
chytrid fungi were considered predominantly free-living
saprophytes, with a few species capable of infecting only
invertebrates and vascular plants. A new species,
was discovered in 1999 which was shown to be capable of
infecting amphibians and causing an often-fatal disease known as
chytridiomycosis. Subsequent studies further showed that
B. dendrobatidis was
associated with frog population declines on every
In the past, chytridiomycosis was considered
to be caused by a single species of fungus, B. dendrobatidis,
but recently another closely related fungus, B.
salamandrivorans, has also been found to be a major cause
for extinction of amphibian species (Martel et al., 2013),
specifically in salamanders.
Similar to B. dendrobatidis, B.
salamandrivorans induces lethal skin disease on infected
amphibians. However, B. salamandrivorans is distinct
from B. dendrobatidis in a number of characteristics:
for example, B. salamandrivorans induces development of
erosive skin lesions instead of hyperplastic/hyperkeratotic skin
lesions; it fails to infect midwife toads in experimental trial;
it has a relatively low thermal preference which suggests
different host specificity and possibly a different effect on
amphibian assemblages than B. dendrobatidis.
amphibians are infected with either one of these fungi, the
fungus can spread quickly
through watercourses and via animal-to-animal contact, and possibly
by other mechanisms not yet fully understood. In Central
America, where the spread of B. dendrobatidis
has been extensively
studied, its rate of progression has been calculated at 28-100
amphibians are not entirely safe from chytrid fungi. Mortality
in private and zoo collections has been reported in several
countries. Various treatment regimes have been used with varying
degrees of success, including antifungal drugs and exposure to
and/or differentiation of these fungal species can currently only be reliably performed by
molecular techniques such as PCR (Annis et al., 2004). Repeat
PCR testing is recommended for confirmation of a fungus-free
environment for amphibians.
Annis, S.L., Dastoor, F., Ziel, H., Daszak, P., Longcore,
J.E. (2004). A DNA-based assay to identify Batrachochytrium
dendrobatidis in amphibians. Journal of Wildlife Diseases 40:
Martel, A., Spitzen-van der Sluijs, A., Blooi, M.,
Bert, W., Ducatelle, R., Fisher, M.C., Woeltjes, A., Bosman, W.,
Chiers, K., Bossuyt, F. and Pasmans, F (2013) Batrachochytrium
salamandrivorans sp. nov. causes lethal chytridiomycosis in
amphibians. Proc. Natl. Acad. Sci. 110: 15325-15329.
or environmental surface swab, or 0.2 ml fresh tissue, or
0.2 ml fixed tissue, or biofilm swab from filter media or tank
Tissue or swab samples may be placed in 70% ethanol if desired;
if so, ethanol volume should be minimized - only use enough
ethanol to cover the head of the swab or the piece of tissue.
if advice is needed to decide which sample type is appropriate
for the specific diagnostic application. For specimen
types other than those listed here, please call to confirm
specimen acceptability and shipping instructions.
specimen types, if there will be a delay in shipping, or during
very warm weather, refrigerate specimens until shipped and ship
with a cold pack unless more stringent shipping requirements are
specified. Frozen specimens should be shipped so as to remain
frozen in transit. See shipping
instructions for more information.
2 business days
polymerase chain reaction