Sexual Dimorphism in Interferon-τ Production by In Vivo-Derived Bovine Embryos

Abstract

Interferon-tau (IFN-τ) is an anti-luteolytic factor responsible for preventing regression of the maternal corpus luteum (CL) during early pregnancy of cattle. In vitro-produced (IVP) bovine embryos first produce IFN-τ as blastocysts. In the present study, we have examined whether sexually dimorphic production of IFN-τ, which is observed among IVP blastocysts, also occurs among in vivo-produced blastocysts, and whether this difference between the sexes persists to day 14 when silencing of one of the X-chromosomes in the trophectoderm is complete. Embryos were flushed from cattle that had been superovulated and bred by Al. Blastocysts (63 male, 62 female) recovered between days 8.5 and 9.5 of ..