凡纳滨对虾性别分化的初步研究

Preliminary Study on Sex Differentiation of Litopenaeus vannamei

通过组织学连续切片与扫描电镜观察,研究凡纳滨对虾的性别分化。结果显示:凡纳滨对虾外部形态的性别分化最早发生在仔虾后第37天,此时在扫描电镜下可观察到雄性附肢的芽基,仔虾后第45天,光镜下可观察到交接器;仔虾后第24天出现原始生殖细胞(PGCS),位于背大动脉的两侧及围心腔膜的腹面,细胞个体及细胞核明显比周围的细胞大,具有强嗜碱性,细胞核圆形或椭圆形,核内染色质清晰可见,随着生殖腺的发育,在第43天出现生殖管,第55天生殖腺可区分为精巢和卵巢。

Sex differentiation of Litopenaeus vannamei were studied by continuous histological sections and electron microscope scanning in the present study. The results showed that sex differentiation of external morphology took place at the 37^th day after postlarva. Blastema of the appendix masculine could be found by electron microscope scanning at the 37^th day, and petasma could be observed under optical microscope at the 45^th day. Primordial germ cells （ PGCS ） of strong basophilic with round and oval nucleus were found at the 24^th day, chromatin in the nucleus could be clearly seen. PGCS were found to be larger than the surrounding cells significantly, and they are located at both sides of the dorsal arteries, as well as ventral of the pericardial cavity. Gonoductus reproductive duct were found at the 43^th day, and ovary and testis could be distinguished at the 55^th day