AN ULTRASTRUCTURAL STUDY ON THE POLYSPERMIC FERTILIZATION IN THE PIG
- VernacularTitle:猪多精受精的超微结构研究
- Author:
Ping XIA
;
Pengchun QIN
- Publication Type:Journal Article
- Keywords:
SEM;
TEM;
Polyspermy;
Pig
- From:
Acta Anatomica Sinica
1955;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
58 embryos at 1, 2, 3 and 4 cell and morula stage were recovered from the oviduct and the uterine horn of the Ha-bai, Du-ha and Du-chang-ha pigs, 24 hours, 2 or 3 days of pregnancy, and were observed with SEM and TEM. The zona pellucida of 1 cell embryo was removed by treatment with 2.5％ pronase for visualization of the cell surface structure.The findings are as follows:1. The surface of the 1 cell stage embryo was densely populated with microvilli and sperm can be found on the surface with its head and tail surrounded by the microvilli and its plasma membrane of the equatorial segment of acrosome intact.2. Many spermatozoa were observed both on the surface and inside the zona pellucida of the 2 celled embryo.3. By the 4 cell stage, some of the spermatozoa had penetrated through the zona and got into the perivitelline space. 4. There were still some spermatozoa on the zona surface of the morula.5. The TEM observation revealed that the heads of supernumerary sperm were located within the cytoplasm of the blastomeres of the embryos from 1 to 4 cell stages and still not decondensed. Some of these sperm heads were actually found within the phagocytic vacuoles of the 4 celled embryos. The ultrastructure of these polyspermic embryos was normal.These results showed that polyspermy in the pig did not intefere with the cleavage of the embryo and the embryo possessed the ability to dispose the excessive sperms.
