Study on features of female fetal reproductive system development in Chinese northeast fine-wool sheep  

作　　者：LIU Yunbo ZHANG Guixue HU Pengfei HUANG He ZHENG Peng LI Wanhua 

机构地区：[1]Northeast Institute of Geography and Agroecology, CAS, Harbin 150081, China [2]College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China

出　　处：《Journal of Northeast Agricultural University(English Edition)》2007年第4期318-322,共5页东北农业大学学报（英文版）

基　　金：Supported by Heilongjiang Province Nature Science Fund(ZJN04-02)

摘　　要：Some charaterasics of female fetal reproductive system were studied in different gestation phases of Chinese northeast fine-wool sheep. The results showed that reproductive system consisted of ovary, oviduct, uterus and genitalia. The fetal ovaries were granular in early phase and became elliptic in later phase. The functional formula of ovarian weight, length and volume was obtained. Primary oocyte was encapsulated by monolayer cells in 7-week fetal ovary cortex. Primordial follicles were formed in 8-week fetal ovary, the follicular cells were sporadically arranged and not always regular. Complete organization of primordial follicles appeared until 10-week gestation, most of them scattered in nests in the following weeks of gestation. Two types of follicular complexes were found in fetal. There were continuous and quick mitosis of oogonia in fetal ovaries, large complexes were formed by oogoniaes encapsulated by multilayer of follicular cells, then they differentiated into small complexes, one or more primary oocytes were formed by mitosis of oogonia, primordial follicles which were caused by follicular cell approaching into them developed.Some charaterasics of female fetal reproductive system were studied in different gestation phases of Chinese northeast fine-wool sheep. The results showed that reproductive system consisted of ovary, oviduct, uterus and genitalia. The fetal ovaries were granular in early phase and became elliptic in later phase. The functional formula of ovarian weight, length and volume was obtained. Primary oocyte was encapsulated by monolayer cells in 7-week fetal ovary cortex. Primordial follicles were formed in 8-week fetal ovary, the follicular cells were sporadically arranged and not always regular. Complete organization of primordial follicles appeared until 10-week gestation, most of them scattered in nests in the following weeks of gestation. Two types of follicular complexes were found in fetal. There were continuous and quick mitosis of oogonia in fetal ovaries, large complexes were formed by oogoniaes encapsulated by multilayer of follicular cells, then they differentiated into small complexes, one or more primary oocytes were formed by mitosis of oogonia, primordial follicles which were caused by follicular cell approaching into them developed.

关 键 词：sheep FETUS OVARY OOGONIA OOCYTE follicle 

分 类 号：S826[农业科学—畜牧学]