大弹涂鱼性腺发育的组织学观察

于光镜下对大弹涂鱼性腺切片作了组织学观察,对大弹涂鱼卵细胞和精子发育规律进行研究。结果表明:大弹涂鱼在一个生殖季节中只能产卵1次,大弹涂鱼属于一次性产卵类型。大弹涂鱼3月卵母细胞进入大生长期发育阶段,4—6月为繁殖盛期,7—8月为繁殖末期。10月卵巢基本修整完毕,进入Ⅱ′恢复期。卵细胞发育可分为6个时相:卵原细胞、卵母细胞单层滤泡、卵母细胞出现脂滴和卵黄、卵母细胞卵黄充满、卵母细胞核极化、卵母细胞退化时相。卵母细胞膜单层,由具有辐射纹的放射带构成,滤泡膜细胞分泌而成的次级卵膜成为成熟卵子的附着丝。大弹涂鱼2月精巢开始发育,5月GSI值达最高值,平均成熟系数达0.70%,排精量最旺盛,出现高峰。7—9月GSI值明显下降。11月至翌年2月GSI值波动于0.08%—0.20%之间,变辐小,此期间精巢处于静止发育状态。大弹涂鱼的精巢属于小叶型结构。精子发育分为6个时期:精原细胞期、精原细胞增殖期、精母细胞生长成熟期、精子细胞变态期、精子成熟期和退化吸收期。繁殖季节精小叶内充满精子,精小囊消失。

OBSERVATION ON THE OVARY DEVELOPMENT OF BOLEOPHTHALMUS PECTINIROSTRIS

Observation on the sexual gland of Boleophthalmus pectinirostris was taken. The morphological structures of ooeyte and sperm development of Boleophthalmus pectinirostris were observed by means of light and electron microscopy. According to the histological characteristics of ovary of the fish, The results showed that it spawned once in a reproductive season. The ovaries began to develop in March. Most of the ovaries reached stage IV and stage V respectively from April to June, which was the spawning season period of the fish with highest monthly average of mature coefficient. The highest mature coefficient of an individual reached the value of 11.2%. Spawning behaviour ended in September. In October, the ovary developed into stage II and remained in this stage from October to next February.The oocyte development could be divided into six phases of oogenesis, which were oogonia, oocyte with a single layer of follice cells, oocyte with lipid droplets and yolk globules, oocyte filled with yolk globules, oocyte with migratory nucleus and degenerative oocyte. There was only one layer of membrane surrounding the oocyte whose radiate lines began to appear in the early time of phase 4. The zona radiate grew to its thickest in the late time of phase 4. There was only one fertilization office cell on the membrane. The spermary began to develop in February. Most of the sperms reached maturation stage in May, The highest mature coefficient of an individual reached the value of 0.70%, exhausted sperms were most exuberant, the peak arose. Mature coefficient fell very obviously from July to next September. Mature coefficient (ranging from 0.08%-0.20%) changed very smally and remained in this stage from November to next February, in thie period, spermary was condition of rest. By the microscope, the spermary appeared to have a lobular-type structure, and the sperm development could be divided into six phases of spermatogenesis, which were spermatogonia period, the proliferation of spermatogonia, the growth and maturity of spermatocytes, the abnormality of spermatid, the maturity of sperm and degenerative sperm. There were many sperms in the lobular cavity in the breeding season. The spermatangium would disappear in that time.