Table 2.
Maturational stage of pig oocytes graded in four categories and cultured thereafter for 12 or 24–28 h
| Grade† of COC | Time of culture (h) | No. oocytes examined | No. (%) oocytes at stage of: | No. (%) oocytes degenerated | |||||
|---|---|---|---|---|---|---|---|---|---|
| GV0 | GVI | GVII‐IV | D | MI | MII | ||||
| 1 | 0 | 53 | 30 (57)* | 22 (42)**,*** | 1 (2) | ||||
| 12 | 31 | 21 (68)* | 10 (32)***,**** | ||||||
| 24–28 | 40 | 1 (3)**** | 2 (5)***** | 30 (75)* | 6 (15) | 1 (3) | |||
| 2 | 0 | 47 | 1 (2) | 18 (38)** | 28 (60)*,** | ||||
| 12 | 32 | 1 (3) | 12 (38)** | 18 (56)*,** | 1 (3) | ||||
| 24–48 | 43 | 38 (88)* | 3 (7)** | 2 (5) | |||||
| 3 | 0 | 55 | 3 (5) | 15 (27)** | 34 (62)* | 3 (5) | |||
| 12 | 37 | 2 (5) | 5 (14)***,**** | 25 (68)* | 3 (8) | 2 (5)**** | |||
| 24–48 | 48 | 3 (6) | 9 (19)**** | 24 (50)** | 8 (17) | 4 (8) | |||
| 4 | 0 | 51 | 1 (2) | 13 (25)** | 36 (71)* | 1 (2) | |||
| 12 | 34 | 2 (6) | 6 (18)*** | 20 (59)*,** | 1 (3) | 3 (9)**** | 2 (6)** | ||
| 24–48 | 78 | 6 (8) | 16 (21)** | 22 (28)***,**** | 11 (14)*** | 17 (22)* | 6 (8) | ||
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.
*−*****
Values with different superscripts in the same column differ significantly (P < 0.05).