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Surrogate mothers don't even have to be the
same species as the clone, as long as they are
from a closely related species (and even that
barrier is being overcome by the manipulation of
the immune system). In the field of embryo
transplantation, a domestic cat could give birth
to kittens from an endangered wild species of cat.
At the Audubon Institute’s Center for Research
of Endangered Species there is a "frozen
zoo" of cells from exotic and endangered
animals. In 2000, researchers implanted caracal
embryos in a domestic cat. She gave birth to twin
test-tube caracals. A domestic cow carried a
cloned Gaur calf.
Looking for a moment at the wider issue of
cloning, it is a concern to those who are opposed
to other forms of animal exploitation. Laboratory
animals (including cats and dogs) could be cloned
for experimentation, especially if they come from
a genetically engineered individual. A goat could
be genetically engineered to produce substances in
its milk; a whole herd of goats can be cloned from
that individual so that the yield is increased.
It's not so far-fetched - antithrombin-3, a
protein in goat’s milk can be a valuable source
in heart medications. Other specific animal
proteins could be mass produced through cloning to
provide necessary ingredients for medications to
help people with diseases such as cystic fibrosis,
diabetes or degenerative diseases. Transgenic
animals (animals containing implanted genes from
another species) could be cloned, perhaps because
their organs can be transplanted into humans.
Artificial
Insemination, IVF and Embryo Transfer
Cloning may be the most advanced and ambitious
aspect of reproductive technology, but it is not
the only technique. Other techniques have already
been refined for use in livestock breeding and in
human fertility treatments.
Sperm can be obtained from an anaesthetized
stud cat by electrical stimulation of the prostate
gland. Anesthetic is required because the stud cat
will almost certainly resent this sort of
handling. All anesthetics carry a small amount of
risk. An alternative would be to collect the semen
in a sort of 'condom' placed inside the queen's
vagina, but to the best of my knowledge this has
not been tested.
The collected sperm is diluted in a suspension
fluid so that the sample can be divided up into a
number of portions. These can be frozen or used
immediately to inseminate a number of cats. This
has the advantage of allowing a cat to impregnate
a greater number of queens, but the disadvantage
of increased inbreeding. In the queen, ovulation
is triggered by the stud's penetration and
withdrawal; this would have to be simulated if
artificial insemination was to be used.
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