Table 1.
Maturational stage of pig oocytes graded in four categories and cultured thereafter for 44 h with or without cumulus investment
| Grade† of COC | Time of culture (h) | No. oocytes examined | No. (%) oocytes at stage of: | No. (%) oocytes degenerated | |||
|---|---|---|---|---|---|---|---|
| GV | D | MI | MII | ||||
| 1 | 0 | 77 | 77 (100)* | ||||
| 44 | 91 | 1 (1)***** | 10 (11) | 79 (87)* | 1 (1)** | ||
| Denuded | 44‡ | 84 | 14 (17)**** | 14 (17) | 50 (60)** | 6 (7) | |
| 2 | 0 | 78 | 77 (99)* | 1 (1) | |||
| 44 | 93 | 1 (1)***** | 18 (20) | 71 (76)* | 3 (3) | ||
| Denuded | 44‡ | 80 | 21 (26)**** | 1 (1) | 15 (19) | 41 (51)** | 2 (3) |
| 3 | 0 | 63 | 60 (95)* | 3 (5) | |||
| 44 | 116 | 21 (18)**** | 37 (32) | 53 (46)** | 5 (4) | ||
| Denuded | 44‡ | 96 | 50 (52)*** | 3 (3) | 11 (12) | 28 (29)*** | 4 (4) |
| 4 | 0 | 69 | 63 (91)** | 6 (9) | |||
| 44 | 99 | 41 (41)*** | 15 (15) | 30 (30)*** | 13 (13)* | ||
COC, cumulus‐oocyte complexes; D, diakinesis stage; GV, germinal vesicle stage; MI, metaphase I stage; MII, metaphase II stage.
†
See text for grade 1–4 COC.
‡
The oocytes incubated for 44 h after their cumulus cells were removed.
*−*****
Values with different superscripts in the same column differ significantly (P < 0.05).