大珠母贝游离珍珠培育研究

Culturing round pearl with Pinctada maxima (Jameson)

2008～2010年，在广西涠洲岛进行了大珠母贝（Pinctada maxima Jameson）游离珍珠培育实验。实验过程中采用解剖法优选植核核位、几种术前处理方法和低温处理小片贝制备外套膜小片等技术，旨在提高育珠贝留核率、成珠率和优珠率。结果表明，在大珠母贝内脏囊缩足肌左右两侧各有一个适合培育游离珍珠的核位，分别称为左袋和右袋，实际操作中只有左袋可以植入珠核培育游离珍珠；不同术前处理实验组的植核贝休养期成活率差异不显著（P〉0．05），但留核率、成珠率显著差异（P〈0．05），其中采用传统术前处理和低温处理相结合的综合术前处理方法可有效提高留核率、成珠率平均达78．2％和80．1％；低温处理小片贝与传统方法制备的大珠母贝外套膜小片的育珠效果（成珠率、优珠率、正圆珠比例）存在显著差异（P〈0．05），且在实验温度范围内，成珠率、优珠率、正圆珠比例随处理温度的降低而增高，在4～8℃达到最好育珠效果，成珠率、优珠率和正圆珠比例分别达到98％、53％和30％左右；在术后休养期，植核贝吐核高峰出现植核后5-t5d，手术伤口愈合时间为15-20d，育殊贝的死亡高峰出现在术后的第20～30天。在水温25～30℃条件下，珠核表面形成珍珠层的时间为45d左右。

The experiment of culturing round pearls with Pinctada maxima （Jameson） was carried out in Weizhou Island of Guangxi province during 2008-2010. Such new techniques as determination of nucleus-inserting site by anatomy, preoperative treatment and saibo low-temperature handling were adopted in the experiment in order to increase the rates of nuclear retention, pearl formation and quality pearls. Results showed that there are two nu- cleus-inserting sites on the left and right of the pedal contractor muscle of the visceral sac in P. maxima which are suitable for culturing round pearls and called left and right pocket. In actual performance, only the left pocket can be used for culturing of round pearls. The difference of survival rate between varying preoperative treatment groups over the recovery period was not significant （P〉0.05）, while the difference of nucleus retention rate and pearl formation rate were significant （P〈0.05）. The average nucleus retention rate and pearl formation rate were increased to 78.2% and 80.1% respectively using a combination method of both traditional preoperative and low-temperature saibo treatment. There＇s significant difference between traditional and low-temperature saibo treatment methods in pearl culturing including pearl formation rate, quality pearl rate and round pearl rate （P〈0.05）. The pearl formation rate, quality pearl rate and round pearl rate were increased with decreased experimental temperature. The best pearl culturing temperature ranged from 4 to 8 ℃ with pearl formation rate, quality pearl rate and round pearl rate of 98%, 53% and 30%, respectively. The nucleus rejection peak occurred at 5-15 d after nucleus insertion, and the wound healing period was 15-20 d. The peak mortality of inserted individuals occurred at 20-30 d after operation. At temperatures 25-30℃, the nacreous layer began to form at the surface of the nucleus around 45 d after operation.