3PN formation may be caused by
polyspermic fertilization or by oocytes derived from meiotic failure.
Low-affinity males can also benefit under these
polyspermic conditions if they are not outcompeted by higher-affinity males (Tomaiuolo and Levitan, 2010; Levitan, 2018).
It is believed that the oviduct microenvironment participates in
polyspermic blocking during in vivo fertilization (LUNO et al., 2013).
In addition,
polyspermic fertilization was reported in the giant scallop Placopecten magellanicus at a pH level less than 7.5 (Desrosiers et al.
Reduction of the incidence of
polyspermic penetration into porcine oocytes by pretreatment of fresh spermatozoa with adenosine and a transient co-incubation of the gametes with caffeine.
Pronuclear location before the first cell division determines ploidy of
polyspermic pig embryos.
Such an androgenetic embryo develops in the cytoplasm of the hybridogenetic egg, through the fusion of two sperm nuclei among the many normally found in these
polyspermic eggs.
The cells had been obtained from
polyspermic embryos that had no chance of implanting in the uterus and that ordinarily would have been discarded.
The researchers used
polyspermic embryos, which result when more than one sperm penetrates an egg.
Spindie-to-cortex communication in cleaving,
polyspermic Xenopus eggs.
Reduction of the incidence of
polyspermic penetration into porcine oocytes by pre-treatment of fresh spermatozoa with adenosine and a transient coincubation of the gametes with caffeine.
However, the proportion of oocytes penetrated and containing male and female pronuclei exceeded 93% in all treatments and the proportion of
polyspermic oocytes was significantly higher as the sperm concentration increased from 0.1-1 to 5-10x[10.sup.6] cells/ml.