凡纳滨对虾人工授精的初步研究

以未交配的成熟雌性亲虾和脱落精荚为实验材料，采用不同精荚破裂处理、不同基础液释出精子、不同保存时间的脱落精荚和不同授精密度进行凡纳滨对虾的人工授精实验。实验结果表明，凡纳滨对虾（Litopenaeus vannamei）脱落精荚的精子在生理功能上是成熟的，可以使卵子受精，受精卵发育正常并孵出无节幼体。网搓法进行精荚破裂处理对精子损伤较少，人工授精的效果比研磨法好；用生理盐水作为基础液释出精子进行人工授精的效果比海水略好；精荚冷冻保存时间越长，其人工受精的效果越差；凡纳滨对虾的精子不具鞭毛，没有运动能力，人工授精的卵子受精率很大程度上取决于精子在水中的密度，增加精子密度可获得较高的无节幼体产量。

Artificial insemination of Litopenaeus vannamei

In hatchery seed production of Litopenaeus vannamei, due to the drop-off of the spermatophores in mating process, the impregnating rate of matured females is usually low, ranging form 50% to 60%, resulting in the waste of resource and increase of production cost. In the present study, matured virgin females were artificially inseminated with the spermatozoa from dropped spermatophores obtained using different spermatophore squeezing methods, treated using different medium solutions, preserved for different durations of time, and inseminated at different densities. The results showed that the spermatozoas from the dropped spermatophores were physiologically matured and able to fertilize eggs and produce normal nauplii. Squeezing spermatophores using screen net had less damage to spermatozoa and better artificial insemination efficiency than using grinders. Physiological saline as dilution medium produced better artificial insemination efficiency than seawater, while longer preservation period for spermatophores caused lower artificial insemination efficiency. Due to zero flagellum and movability of Litopenaeus vannamei spermatozoa, the fertilization rates to a great extent depended upon the spermatozoa density in water, increasing fertilization rate and nauplii production with increasing density of spermatozoa.