Abstract:

【Objective】 This study was aimed to investigate the distribution of FSHR (FSH receptor) on the ovaries among different local breeds of sheep by different efficiency of superovulation, and to do some preparations for further improving this ovine propagation technique. 【Method】 Three local ovine breeds were selected depending on their different own sensitivity range to superovulation by FSH as following: Small Tailed Han sheep, White Tan sheep, and Ujumqin sheep. At 8, 16, and 24 hour after the last injection with FSH, the ovine ovaries were collected and treated by immunohistochemical staining to observe the distribution of FSHR on their different ovarian follicles.【Result】The results showed that FSHR was expressed mainly on granulosa cells. At 8, 16, and 24 hour after the last injection with FSH, the FSHR levels on the ovarian follicles of Small Tailed Han sheep, were significantly higher than those of the other two breeds, while the FSHR levels in early and middle ovarian follicle of White Tan sheep, were also higher than Ujumqin sheep(P＜0.05). At 8, 16, and 24 hour after the last injection of FSH, the FSHR levels in the late ovarian follicle of those three breeds were significantly higher than those in the early and middle ovarian follicle(P＜0.05). The results showed that the responsive orders to FSH treatment of these three different local ovine breeds be one by one as following: Small Tailed Han sheep＞White Tan sheep＞Ujumqin sheep.【Conclusion】It can be concluded that there is a relation between the effect of superovulation among different local sheep breeds and the distribution of FSH receptor on their ovaries.

Key words: sheep, superovulation, follicle-stimulating hormone receptor, immunohistochemical staining