A key factor for the low efficiency of IVP porcine embryos is the high rate of polyspermy
(TOKESHI et al.
Fertilization in natural populations of the dioecious brown alga Fucus ceranoides and the importance of the polyspermy
Even if we insist that some central control is present in the hydatidiform mole--a possibility that makes more sense, perhaps, in the hydatidiform mole that suffers from polyspermy
, since the presence of the maternal pronucleus allows for the possibility of the development of the body of the embryo proper--we would have to note that this controller is profoundly defective, so that the developing organism is doomed to die.
Low intracellular egg pH may prevent fertilization and subsequent development as well as slow the time that the fast block to polyspermy
is established (Desrosiers et al, 1996; Kurihara, 2008; Reuter et al, 2011a).
Under in vivo condition, polyspermy
is controlled in part by the regulatory role of the oviduct (18).
Zona bock Biochemical changes in the oocyte that prevent more than one sperm from binding to the zona pellucida, thereby preventing polyspermy
in press): (1) response to pathogens; (2) sexual selection by male-male competition; (3) female choice; and (4) avoidance of polyspermy
(fertilization of an egg by more than one sperm).
However, such blockages apparently occur via alternative mechanisms, since the SFK antagonist PP2 promotes polyspermy
The effects of exposing the sperm to GAGs on the rate of polyspermy
and on formation of 2 pronuclei (2 PN) at 18 h after insemination was examined (Table 1).
resulting from high sperm density could be the cause of the abnormal development.
Meiotic arrest maintained by cAMP during the initiation of maturation enhances meiotic potential and developmental competence and reduces polyspermy
of IVM/IVF porcine oocytes.