条石鲷卵巢发育的组织学研究

Histology of ovary development in striped knifejaw Oplegnathus fasciatus

采用常规的生物学调查和石蜡组织切片法,对条石鲷Oplegnathus fasciatus卵巢发育周期和卵巢发育中各个时期卵母细胞的形态特征以及产卵类型等进行了组织学研究。结果表明,条石鲷卵母细胞的发育过程在年周期中可分为6个时相：Ⅰ时相的卵母细胞呈原始分化状态,Ⅱ时相卵母细胞出现明显的卵黄核,Ⅲ时相卵母细胞出现皮质液泡,Ⅳ时相的卵母细胞分化明显,卵黄颗粒部分融合,Ⅴ时相和Ⅵ时相分别为卵子形成和退化吸收时相。卵巢发育可分为6个时期：繁殖期主要在5—7月,其卵巢有Ⅳ期、V期;8月卵巢开始退化,9月进入重新发育的Ⅱ期,直到翌年3月都为越冬Ⅱ期卵巢;3月下旬条石鲷卵巢开始重新发育为Ⅲ期卵巢。条石鲷卵巢的平均成熟系数为0.70%~12.57%。组织学观察结果表明,各时相卵母细胞发育不同步,因此条石鲷属多次产卵。

This paper described the morphology,histology and annual change in ovary development in striped knifejaw Oplegnathus fasciatus by means of microscope.The development of the oocytes can be divided into six stages： the oocyte differentiation in the phase Ⅰ,the yolk nuclei with very distinction in the phaseⅡ;the appearance of unilayer vacuoles in the phage Ⅲ;the amalgamation of the yolk within the oocytes in the phase Ⅳ;the formation of the ripe eggs in the phase Ⅴand the degenerated oocytes in the phase Ⅵ.The main reproduction season extended from May to July,during which the ovary was variously found to be in stages Ⅳ and V.The ovary was found to be degenerated from August.The ovary developed again into the Ⅱphase from September.Until next March,the winter ovary was in stage Ⅱ.From the late March,the ovary developed again into the Ⅲ phase.The average gonado-somatic index of the ovary was found to range between 0.70% and 12.57%,indicating Oplegnathus fasciatus being among the multiple spawning species.