K. PavasuthipaisitY. KitiyanantC. ThonabulsombatC. TocharusS. SriurairatnaK. L. WhiteMahidol UniversityUniversity Logan2018-08-102018-08-101992-01-01Theriogenology. Vol.38, No.3 (1992), 545-5550093691X2-s2.0-38249010277https://repository.li.mahidol.ac.th/handle/20.500.14594/22242The present experiment was carried out to evaluate the maturation, fertilization and subsequent embryo culture of swamp buffalo oocytes in vitro. The oocytes (n=273) were collected and morphologically graded based on the structure of cumulus-oocyte complexes as Grade 1 (compact, n=81), Grade 2 (expanded, n=70), Grade 3 (partially denuded, n=65) or Grade 4 (completely denuded, n=57). More than 60% of the in vitro matured oocytes co-cultured with capacitated spermatozoa demonstrated evidence of fertilization or cleavage to the 2-cell stage when either Grade 1 or 2 oocytes were used. The percentage of fertilized oocytes undergoing 2-cell stage cleavages from Grade 3 (53%) and Grade 4 (46%) groups was significantly lower (P<0.01) than that observed in the Grade 1 (64%) and Grade 2 (68%) groups. Development to the 6 to 8 cell stage substantiated fertilization of Grade 1 and 2 oocytes. These results demonstrated that swamp buffalo oocytes are capable of maturing in vitro, forming embryos, and developing at least to the 8-cell stage in culture medium alone. © 1992.Mahidol UniversityAgricultural and Biological SciencesVeterinaryArticleSCOPUS10.1016/0093-691X(92)90074-2