Effects Of Hormone Stimulation On Lamb Follicular Development

The objective of this study is to analysis the relationship between the body weight and oocyte development. This study was performed by: (1)Three groups lambs of different body weight were stimulated by multiple dose of FSH and a single injection of PMSG. The oocytes were cultured for observing cladvage rates and blastocyst obtained by 1aparotomy oocytes recovery from donors; (2)?A multivariable hormone concentration analysis was used to investigate the relationship between the body weight and follicles numbers; (3)Lambs of mimilar body condition were stimulated repeatedly with same hormone and cultured oocytes.The results were as follows: (1)The number of oocytes of group M(15.9±2.03kg) were significantly higher than the other two groups(P<0.05). (2)The cleavage and mulberry / blastocyst rates of oocytes from Group W(20.4±1.08kg) were higher than those from Group M (15.9±2.03kg) and Group L(13.2±0.98kg),and the mulberry / blastocyst rates of oocytes from Group W was significantly higher than Group L(P<0.05). (3)Hormone assays indicate concentrations of FSH,LH and E2 of lambs from Group W were higer than that from Group L and Group M. (4)The number of follicles and oocytes from repeat treatment were significantly lower than the initial treatment(P<0.01). It is concluded that the number of oocytes and the development capability of oocytes from the middle weight lambs were better than the other two groups, and the oocyte recovery from the group that treatmented repeatedly was less than the first treatment.