Abstract:

【Objective】 The impact of TGF-β receptors (TGF-βRⅠ,TGF-βRⅡ) on the number of ovulation was studied by analyzing the tissue expression pattern and the relationship between the mRNA expression level of TGF-β receptors and the number of ovulation. 【Method】 Sixteen multiparous ewes were selected to investigate, eight which bred multi-lamb were used as the high-yield group, the other eight which bred single lamb were used as control group. Cloprostenol sodium were injected to make the synchronization of estrus treatment, then slaughtered within 48-60 h after empathema, two side ovaries were collected after slaughtering, the number of corpus rubrum on the ovaries was counted to deternine the number of ovulation; the tissues such as hypothalamus, hypophysis were collected from one ewe in the high-yielding group, to make a tissue expression analysis. The relationship between the mRNA expression level of TGF-β receptors and the number of ovulation, which were detected by real-time fluorescent quantitative PCR, were analyzed.【Result】 TGF-βRⅠ’s relative expression level in the reproductive organ was only significantly higher than in the lung and muscle (P＜0.01). TGF-βRⅡ’s relative expression level in reproductive organ was significantly higher than that of other tissues (P＜0.01), it is a high-expressed gene in ovary. TGF-βRⅠand TGF-βRⅡ’s mRNA expression level in the ovaries of the high-yield group were significantly higher (P＜0.01) and obviously higher (P=0.011) than the control group, respectively. TGF-βRⅠand TGF-βRⅡ’s mRNA expression level have a positive correlation with the number of ovulation, the correlation coefficient were 0.562 (P＞0.05) and 0.711 (P＜0.05), respectively. 【Conclusion】 TGF-β receptors showed the high level in ovary, TGF-βRⅠand TGF-βRⅡ’s mRNA expression level in the ovaries of the high-yielding group were extremely or obviously higher than the control group, furthermore, it had a positive correlation or a significant positive correlation with the number of ovulation, so it illusted that TGF-β receptors have a close relationship with high-yielding Hu sheep.

Key words: Hu sheep')">Hu sheep, number of ovulation, TGF-βRⅠ, TGF-βRⅡ, correlation