| After breeding, judging the cow whether is pregnant as soon as possible, may promote pregnant cows'raise and management, breed again in time or take some necessary measures.It is important to shorten procreative interval and advance the reproduced ability. This experiment has utilized the semi-quantitative PCR technology and the mRNA difference display technology separately, to exploringly study the early pregnancy diagnosis methods based on the PAG gene expression quantity in the cows'blood as well as the non-pregnant and the pregnant cows'gene expression difference in the blood. From the molecular level,to understand gene expression's change rule during the early pregnant diagnosis process, which provides the reference to the research of mammal early pregnancy diagnosis's new method. The results are as follows:The PAG gene had the expressed both in non-pregnant and pregnant cows'blood, the PAG gene expression quantity in pregnant cows'blood is slightly higher than non-pregnant cows, but the difference is not remarkable, t=2.36950.05. This also shows that judging whether the cow is pregnant by examining the PAG gene expression quantity in blood on the 21st day after breeding is unpractical.Altogether screened six special expression fragments separately in the pregnant cows'blood, passed through the sequence and the contrastive analysis, indicated that had 3 bandings and the known function gene or the regulative gene is similar, other bandings for unknown function gene or not similar gene. And: The S1 sequence has the high homology (98%) with the transforming growth factor2 (TGF-β2), TGF-β2 has the promotion proliferation function to cows'trophoblast and the endometrial epidermis, but has the inhibitory function to the growth of the epithelial cell and plunge the trophoblast; it also has the promotion proliferation function to reforming variated endometrium of human and the domestic animal epidermis .The S4 sequence has the high homology (97%) with the clony- stimulating factor 1 (CSF 1), CSF 1can stimulate the early placenta to grow, but can also suppress the NK cell's function, reduce miscarries.The S5 sequence has the high homology (97%) with the Insulin like growth factor 1(IGF1), IGF1 mainly has an effect through the membrane acceptor, may stimulate the placenta to release the prolactin, adjust the synthesis and the secretion of other steroid hormone.IGF1 has relationship with the implantation of blastocyst, the form and function of placenta, and the growing development of embryo, it also can promote the soakage of trophocyte, and is propitious to the preimplantation; it participated in the many link's adjustments during early pregnancy, and is the important effect factor of embryonic development. |
