孔雀鱼雌性生殖器官组织结构及卵子发生的研究

Histology of female reproductive system and oogenesis process of guppy(Poecilia reticulata)

应用光镜技术研究了孔雀鱼(Poecilia reticulata)雌性生殖器官组织结构和卵子发生的特点,以期为孔雀鱼的良种繁育工作提供基础资料。结果表明,孔雀鱼雌性生殖器官由卵巢、卵子输送管和泄殖孔构成。卵子发生过程经历了6个时相:第Ⅰ时相主要为卵原细胞;第Ⅱ时相是处于小生长期的初级卵母细胞,形成生长环、卵黄核和单层扁平滤泡细胞膜;第Ⅲ时相是进入大生长期的初级卵母细胞,卵黄开始积累,形成2层滤泡细胞膜和2层卵包膜;第Ⅳ时相为发育晚期的初级卵母细胞,细胞发生了极化,卵包膜发育完善;第Ⅴ时相发育成熟,卵黄颗粒凝结呈块状,卵黄泡主要分布于细胞膜内缘,滤泡细胞膜萎缩;第Ⅵ时相是闭锁卵泡,被滤泡细胞消化和吸收转变为卵巢内结缔组织。

To provide reference for seed breeding of guppy （Poecilia reticulata）, we investigated the histology of its female reproductive system and oogenesis process by light microscopy. Results indicate that the female reproductive system of guppy was made up of ovary, ovum delivery ducts and cloaca. Oogenesis process of guppy experienced 6 stages： At Stage Ⅰ, oocytes were mainly composed of oogonia. At Stage Ⅱ, primary oocytes reached small growth stage with growth loop, yolk nucleus and one layer of follicular membrane. At Stage Ⅲ, primary oocytes forming 2 layers of follicular membranes and egg envelopes reached great growth stage, and yolk granules began to accumulate. At Stage Ⅳ, primary oocytes reached late phase with cell polarization and completely developed egg envelopes. At Stage Ⅴ, oocytes matured and yolk granules condensed, vitelline foam almost distributing in the inner edge of cell membrane and follicular membrane shrivelling. At Stage Ⅵ, atretic follicles were digested and absorbed into connective tissue by follicular cells.