Candidate gene determining growth and development difference in sex-control IVF and in vitro embryo.

Transferring bovine sex-controlled IVF embryo usually lead to large offspring syndrome(LOS)which seriously influence the growth and development of fetus.The experiment was conducted to explore the effect of tranfering sex-controlled IVF embryo and choose the skeletal muscle produced by sex-controlled IVF embryo and AI as the experimental material,choose 4 genes(IGF1,IGF2,myostatin and MHC2a)which are closely related with growth and development to study the expression difference of sex-controlled IVF embryo and fetus of AI.The result showed that the pregnancy rate was 34.61%(344/994) after transferring sex-controlled IVF embryo of vitrification.It is obviously higher than pregnancy rate of conventional frozen method 29.18%(P0.05).The birth weight and chest circumference were significant different(P0.01) between of sex-controlled IVF embryo and fetus of AI.The expression of IGF1,IGF2,myostatin and MHC2a of sex-controlled IVF embryo and AI embryo had significant changes at different development stages of fetus.It may be one of the reasons leading to the large offspring syndrome.