| 1. Two methods, surface cutting and aspiration, were used for recovering of the usable cumulus-oocyte complexes (COCs) from surface-visible follicles of slaughtered goat ovaries. The average total number of COCs recovered per ovary was 4.95 (20794/4201) by surface cutting and 2.86 (1029/360) by aspiration. There is significant difference between the two methods for collection of the COCs in goat. COCs were collected from slaughtered goat ovaries during the breeding (from Oct to Jan) and nonbreeding (from Mar to Jun) seasons by surface-follicles cutting. The average total number of COCs recovered per ovary was 4.50 (3160/702) and 5.17 (3134/607), respectively. There is significant difference between the numbers of COCs collected from the two seasons. The results show that the recovery of COCs from slaughtered goat ovary by surface-follicles cutting is simple and efficient compared with the aspiration. And more COCs can be recovered by surface-follicles cutting during the nonbreeding season than the breeding seasons. 2. Usable goat CQCs recovered by surface-follicles cutting from breeding seasons and nonbreeding seasons were matured in vitro. The percentage of maturation were 67.7% (2223/3286) and 74.1% (2440/3295), respectively. The results show that COCs recovered from nonbreeding seasons were better than from breeding seasons. The maturation rate of COCs collected from ovaries transported for 6-8h at 20-24XD, 25-29C and 30-35C, was 69.9% (2039/2916), 69.5% (4713/6779) and 56.1% (394/702), respectively. The results suggest that slaughtered goat ovaries can not be placed above 30~C for long distance transporting. The maturation rate of the goat oocytes with diameter (including the zona pellucida) rJ <150 im, lSOpm< i <160 and tL >160gm, was 0% (0/120), 70.5% (229/325) and 79.6% (86/108), respectively. The results show that goat oocytes have acquired full meiotic competence at a diameter of 150 tm. There were no differences between the maturation rates of goat oocytes cultured in medium supplemented with FSH/LH 68.9% (1813/2633) or with HMG74.2% (2637/3556). The maturation rate was not promoted when the medium was supplemented with lOng/mi EGF. 71.2% (826/1160) and 70.0% (403/576) extruded the first polar body after culture in vitro in the medium with EGF and without EGF, respectively. 3. The percentage of cleavage was 10.4% (42/403) and 10.7% (31/289), when the goat oocytes were activated for 7 mm by 7% and 8% ethanol, respectively; The percentage of cleavage obtained from goat oocytes activated by 10% and 20% ethanol for 5mm were 11.0% (31/282) and 7.1% (3/42), respectively. 12.9% of goat oocytes became cleavage when they were activated by 10% ethanol for 10mm. The results indicate that goat oocytes cannot be activated by 7% to 20% ethanol. When goat oocytes were activated by Sr2 -CB for 6h, 12h, 16h and 24h, the percentage of cleavage of goat oocytes were 2.2% (3/139), 80.4% (43 6/542), 78.8% (178/226) and 70.1% (60/85), respectively. And the proportion of oocytes developing to the blastocyst stage were 0% (0/139), 15.6% (68/436), 10.1% (18/178) and 1.6% (1/60), respectively. The results showed that goat oocytes cannot be activated by Sr -CB for 6h, and there were no differences between the cleavage rates among the other groups activated by Sr2 -CB for 12h, 16h and 24h. But the best results came from goat oocytes activated by Sr2 -CB for 12h. When goat oocytes...
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