on blood collected prior to death), indicated
severe dehydration, electrolyte imbalances with
hypokalaemia, and significantly raised muscle
enzymes (CK and AST).
Pathology
The animal died shortly after becoming recumbent
and a post mortem was performed. The stand out
features at post mortem examination were of an
over-conditioned animal, severe cardiac endocardial
haemorrhages with suspected myocardial necrosis
accompanied by severe pulmonary oedema and
abundant tracheal foam. Histological examination
of formalin-fixed tissues collected at post mortem
revealed extensive myocardial degeneration and
necrosis as the most significant lesion.
Mineral Analysis
Fresh liver collected at post mortem was submitted
for quantitative mineral analysis. Copper levels were
extremely low confirming a long-standing copper
deficiency in this antelope. The liver selenium
levels reported were likely associated with the prior
application of a selenium injectable product, while
magnesium, calcium and phosphate levels in liver
are not reliable indicators of their status. For theses
minerals (calcium, phosphate, magnesium) blood
levels are preferred to interpret mineral status.
Interpretation
“Falling disease” of cattle which has been described
in Australia and Florida, USA is a syndrome of sudden
death believed to result from prolonged copper
deficiency characterised by extensive myocardial
degeneration and necrosis. Considering this
information copper deficiency myocardial necrosis
is suspected in this roan antelope. The blood results
provided also raise concerns about hypokalaemia,
hypophosphatemia and hypochloraemia shortly
before death and such electrolyte imbalances
could have had fatal consequences on an already
compromised myocardium. The clinical chemistry
results would be consistent with those expected in
an animal with metabolic imbalances and the CK and
AST levels would fit the nature and duration of the
myocardial pathology.
This case highlights the growing importance of
performing mineral analyses on wildlife patients
particularly considering the rapid intensification that
the industry is experiencing. Knowledge pertaining
to the preferred sample type for a minerals analysis
is important to ensure that control measures
implemented are based on scientifically sound and
relevant data. When investigating translocation
associated conditions in addition to the common
capture (exertional) myopathy syndromes one must
also consider electrolyte imbalances (transport tetany)
and underlying nutritional / toxic cardiomyopathies as
possible contributing factors.
The high incidence of wild cheetah
mortality during immobilisation
https://vimeo.com/216822289
Vincent C van der Merwe
Endangered Wildlife Trust, Private Bag X11,
Modderfontein, 1645, Johannesburg
A metapopulation of 332 wild cheetahs (Acinonyx
jubatus) exists on 51 small fenced reserves in South
Africa.
These reserves range in size from 30km2 to over
1000km2 and each hold between one and 30
cheetahs. All metapopulation reserves have predator
proof fencing, preventing opportunities for natural
gene flow between populations. Genetic evidence
accumulated since 1980s shows that genetically
effective population size of 50 individuals is
inadequate for preventing inbreeding depression over
five generations in the wild. A population of at least
100 individuals is required to limit loss in total fitness
to less than 10%. However, at least 1000 individuals
are required to retain evolutionary potential for
fitness in perpetuity.
2017
MAY
19