Screening Of Early Pregnancy Factors In Vaginal Secretions Of Sheep

Early pregnancy factor(early pregnancy factor,EPF)is a protein related to mammalian pregnancy.It is the earliest immunosuppressive factor and growth factor detected in serum after fertilization in mammals.Studies have shown that a series of responses produced by oocytes after fertilization can cause changes in early pregnancy factors,so they can be used as indicators for the detection of ultra-early pregnancy,and the body will have a tendency to decrease early pregnancy factors before abortion.Therefore,early pregnancy factor plays an important role in the detection of super-early pregnancy and the prediction and diagnosis of abortion.The purpose of this study was to identify the factors of early pregnancy in vaginal secretions.A stable and regular early pregnancy factor was selected to detect super-early pregnancy in domestic animals.80 ewes of the same body condition were selected for simultaneous estrus treatment,48 hours after injection of sodium chloride and 72 hours after injection,30 ewes with the same estrus time were randomly selected for breeding.The estrus of the selected ewe was tested on the 14 th ~ 17 th day after mating.The result was that 6 estrus were estrus again,6 ewe were judged as estrus ewe,and the other 24 ewe were pregnant ewe.Twenty-four pregnant ewes were divided into two groups: group I and group ?.Group I was used as the control group for estrus.The number of ewes in group I should be the same as that of estrus ewe,so the number of ewe in group I was 6.Then the number of ewe in group II was the remaining 18.Six estrus sheep were divided into group ? and group ?.The expression of early pregnancy factor gene m RNA and the content of progesterone in group ? were compared with those in group ?.Samples were collected from 30 ewes at 0,5,10,13 days after mating,and the test group was conducted on the 14 th day.After grouping,the ewes of group I and group ? were collected on the 15 th,20th,25 th day after mating,and the samples of group ? were collected on the 16,19,25 days after mating.It is related to JAK/STAT signal transduction pathway and progesterone change.The factors of early pregnancy were screened.After sampling,the m RNA expression of early pregnancy factor-related gene Cox1,Cox2,Jak2,Stat1,Isg15,Mx1,Oas1 was detected by q PCR,and the protein expression of early pregnancy factor-related gene Cox1,Jak2,Mx1,Isg15 was detected by Western Blot.The levels of progesterone in vaginal secretions of pregnant ewe and estrus ewe at different stages were compared by using sheep progesterone(PROG)Elisa kit.The results were as follows:(1)By comparing the changes of progesterone content with the expression of Cox2 gene,it is concluded that the antagonistic effect between the two was not obvious before 15 days of breeding,and the antagonistic effect between the two was obvious after 15 days of breeding.(2)The expression of IFN? stimulating gene Isg15 is of great significance to the identification of early pregnancy of sheep,and can be used as a diagnostic index of early pregnancy factor.These results suggest that Isg15 is the most suitable one of the 7 genes associated with early pregnancy factor for detection of ultra-early pregnancy.