الفهرس 
Methods of oocyte recoveryOnly 14 pages are availabe for public view
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Abstract
Horse industry is very large and important part of world economies. It is
diverse, involving agriculture, business, sport, gaming, entertainment and
recreation.
The economic study done by the American Horse Council Foundation in
2005 validates the importance of the horse industry, that the horse industry is a
highly-diverse, national, serious and economically significant industry that
deserves the attention of the general public, the media and governments.
The horse industry has a direct economic effect on the U.S.A of 39 billion Dollars
annually (American Horse Council, 2010)
In Egypt, there are 230 farms for breeding Arabian horses. The Egyptian
Arabian horse is one of the outstanding and most expensive horses in the world.
Nowadays there is an increasing interest in obtaining foals via assisted
reproductive technologies from mares that die suddenly or must be euthanized for
medical reasons. In these cases, the mare’s ovaries may be harvested postmortem
and processed for oocytes recovery. The recovered oocytes are matured in vitro
and can then be used for oocyte transfer (Carnevale et al., 2004).
Assisted reproductive techniques in equine have been developed to obtain
pregnancies from subfertile mares and stallions and to save gametes after death as
well. In recent years, these procedures have been used for clinical cases with
repeated success (Carnevale and Maclellan, 2006). from an historical prospective, the development of assisted reproductive
technologies in the horse dates back to the late nineteenth century when Sir
Walter Heape established the first equine pregnancy obtained by artificial
insemination (Heape, 1898). Since that time, progress in assisted reproduction in
the horse has been continuous although at an irregular pace compared with other
domestic species. Besides artificial insemination, which is now well developed in
the equine industry (Squires, 2005), other technologies based on in vivo and in
vitro procedures of embryo production have emerged only in recent years. This
situation is in sharp contrast with the rapid development and application of such
technologies in several other species including cattle, sheep and pigs, to the point
of successful commercial exploitation.
Producing embryo by in vitro fertilization (IVF) can be done based on three
subsequent techniques: in vitro maturation (IVM) of oocytes, IVF of matured
oocytes and then in vitro culture (IVC) of fertilized oocytes for cleavage up to
blastocyst stage (Goswami et al., 2004).
Oocyte maturation is the first and the most critical step towards successful
in vitro embryo production (Abdoon, 2002).
Proper nuclear maturation and cumulus cells expansion are essential for the
maturation process and continued viability of oocyte following fertilization
(Fukui and Ono, 1989). The culture medium and selection of protein
supplements and hormones for IVM play an important role in the subsequent
maturation rate, and embryonic development following IVF (Bavister et al.,
1992).
In many domestic species, IVF has been successful in yielding live
offspring as well as advancing research and application. In the equine, however, a
low fertilization rate and low in vitro development of transferable embryos have
continued to impede this technology. This is partly due to difficulty in obtaining
slaughterhouse material and thus limited availability of mature oocytes for IVF
(Hinrichs et al., 1993; Alm and Torner, 1994) and the lack of an efficient in
vitro capacitation system for stallion spermatozoa (Ellington et al., 1993).