Anuario Raza Polo Argentino Anuario2018 | Page 251

at any time, thereby permitting embryo production
the year round. These embryos are frozen and
transferred to receptor mares whenever the
breeder wishes.
Barren mares: once the immature oocytes are
obtained through follicular aspiration, all the rest
of the process occurs in vitro, which is ideal in the
case of barren mares.
Barren stallions: Since the spermatozoon is
injected into the oocyte, we are in a way making
things easier and it is not necessary that there be
millions of normal sperms available.
Limited reserve of frozen or low-quality semen: the
use of frozen semen may be maximized since a
semen straw may be cut into little bits or even in
some cases allowed to thaw and then freeze again
in more diluted form so as to be able to count on an
almost unlimited reserve of semen.
Dead mares: for cases in which a mare must be put
down due to injury or sudden death, for example,
in the case of a colic, it is possible to obtain a last
pregnancy by taking oocytes to be found in the
ovary. Immediately after the death of the animal,
the ovaries must be sent to the laboratory where
the oocytes are removed and cultivated in order
to be later injected with a spermatozoon from the
stallion chosen. This could have been the case of
many famous mares that became injured while
playing and were put down.
Dead stallions: something similar could be done
with stallions that for different reasons (colic; injury;
accidents) die abruptly or must be put down. If the
testicles are sent immediately to the laboratory,
it is possible to obtain the sperm present in its
epididymis and vas deferens. Those sperm cells
are frozen and are enough to achieve pregnancies
through ICSI technique.
In summary: technological advancement in
latter years has provided the breeder with new
tools that make possible the production of
female embryos at any time of the year, from
both barren and fertile animals and which may
be preserved frozen and transferred in order to
schedule foaling.
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