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In November of 1995, the South China tiger team arrived in China
to train zoo staff how to manage and medically evaluate captive
tigers at Shanghai, Suzhou, Chongqing and Guangzhou Zoos. Physical
exams, identification and biomaterial collection procedures were
performed on 22 of the then 50 South China tigers in captivity.
Semen was collected and sperm was cryopreserved from six tigers
so a Genome Resource Bank for South China tigers could be initiated
by the Chinese Association of Zoological Gardens. Tiger health
management and husbandry procedures, exhibit and facility design,
and nutrition were assessed at each zoo. A demographic and genetic
analysis was performed on the captive population. Physical examinations
were performed including assessment of general condition, evaluation
of eyes, ears, claws, and teeth. Identification procedures for
all cats included a studbook number tattoo on the inside of the
right rear leg and a "Trovan" transponder placed under
the skin of each tiger. Samples collected include whole blood
for health testing and skin biopsies and hair samples for genetic
evaluation.
In general, the tigers appear to be in good health pending results
of blood and serum tests. The most significant common health concern
is fractured canine teeth. 15 fractured canines were found in
9 animals. Fractured teeth may compromise long-term animal health.
The greatest health concerns for these highly endangered tigers
is the vulnerability of the population to disease outbreak and
the lack of baseline data on disease problems in the population
as a whole.
 In
the past, the South China tiger has been managed at the institutional
level based on the needs of each zoo and its relative success
in breeding certain individual animals. This approach, however,
will not be sufficient for long-term maintenance of a healthy
captive population. The living South China tiger captive population
is based on only six wild-caught founders and has retained 78%
of the original gene diversity of these founders. Given this critical
situation, it is imperative to manage the South China tiger as
one large collective population in a cooperative program among
Chinese zoos. A census of the captive South China tiger indicates
a decline in population size over the past few years. Furthermore,
there are few animals under the age of three, which will continue
the negative growth rate. It is therefore essential that the number
of breedings be increased to produce a positive growth rate. It
is not known whether the limiting factor is cage space or failure
of breeding animals to reproduce.
The South China Tiger Masterplan will contribute toward further
conservation for the South China tiger. The captive program is
vital for prevention of loss of genetic diversity and the extinction
of this subspecies. Preliminary evaluations indicate that the
captive South China tiger population has several critical issues
that must be addressed. Overall, the captive population is declining,
the average inbreeding coefficient is high (0.25), neonatal mortality
is high (90%, except at Suzhou where it is 10%), and many adult
males have poor quality sperm. Of greatest concern is the need
to increase the reproductive output of this captive population.
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