中国对虾雄对虾交配能力和精荚再生的研究

STUDES ON THE MATING ABILITY AND SPERMATOPHORE REGEMRATION IN MARINE SHRIMP PENAEUS CHINENSIS

于1987年对中国对虾雄对虾交配能力进行实验观察；于19941995两年进行补充实验。结果证明，在实验室条件下，保持雄对虾的相对数量而且有充足雌对虾供交尾选择的情况下，中国对虾雄对虾在一个交配季节中的自然交配能力可达到3—4次；交配后生成新的精荚并再次发生交配的平均时间约为3d，但部分雄对虾交配次日即可生成新的精荚并再次发生交配行为；雌雄性比5：1和2：1对雄对虾在整个交配季节中的累计平均交配率没有明显影响。但在交配盛期，雌雄5：1实验组的累计交配率为2．6次，而21两个实验组的累计交配率只有1．13和1．43次，说明较多可供选择的雌对虾的存在，对雄对虾在一定时期内的交配能力和精荚再生可能有诱导作用。

This paper deals with the mating ablity and spermatophore regeneration of marineshrimp Penaeus chinensis under laboratory conditions. Unmated culthed shrimp with body lengths of13.5- 15.7 cm were used in the experiments. Initial observations were made in 1987, andsupplementary experiments were carried out in 1994 and 1995. Unmated male and female shrimpwere stocked separately in indoor tanks and employed for experiments after one week acclimation.=5:1 and 2:1 were arranged to test the effects of different sex ratio on mating ablity andspermatophore regeneration in male P chihensis. The daily mating rate is defined as the number ofmated females divided by tha of males in the tank. The ascumulated mating rate (AMR), is used toindicate the average mating ablity of the males in eash trial, is obtained by summing up the drilymating rate of the trial during the mating season. The following formula is used to calculate AMR:Whre n is mating days, mf is the number of mated female, and M is the number of male used foreanh trial. Main results were as folowes.1. In laboratory conditions, the natural mating ablity of male P. chinensis might attain 3-4times, but depended on the relative number of the males and females available for mating selection.2. The average time needed for males to regenerate new spermatophores after mating and againwith mate females was around 3 days. Some male shrimp might regenerate new spermatophores andmating was obeerved again in the very next day.3. The finding that in the 5 day frequent mating period, AMR in the two trials of = 5:1were 2.60, while AMR in the two trials of = 2:1 were only 1.13 and 1.43, respectively,indicated that in this period. more females were availabe for mating selection, and so might induceand / or promote the male's mating ablity and spermatophore regeneration.4. There were no significant differences between the AMR obtained from the whole matingseason for trials of and those of which indicated that the potential matingability of male P chinensis was determined by its biological characteristics. Even though higher ratioof female might induce more mating of the male in the short term, it could not enhance the male'spotential mating ability.5. The fastors which influenced the mating ability and spermatophore regeneration of male P.chinensis were the shrimp's state of health, temperature, sex ratio, male's maturity, light intensity,stocking density, etc., while molting of the female is an absolute necessity for P chinensis to mare.