Generation of viable calves derived from developmentally mature blastocysts produced by on-gel culture

Abstract

Conventional culture systems for bovine embryos are unable to support sustained embryonic development until the developmentally mature blastocyst stage. Although we have previously developed an on-gel culture system that enables bovine blastocysts to complete cell segregation events at day (D) 10 following in vitro culture, the development of D10 blastocysts to term has yet to be achieved. In this study, we attained full-term development of D10 mature blastocysts produced using an on-gel culture system. Two calves derived from on-gel-cultured embryos were vaginally born, showing normal birth and placental weights and no obvious morphological abnormalities. Moreover, we detected no abnormalities in blood metabolic profile analyses. Our findings indicate that on-gel culturing can be used to facilitate the development of developmentally mature blastocysts to term, and produce healthy viable calves. This culture system could make a valuable contribution to cattle production and would enable a range of analyses for characterizing bovine-specific pre-implantation development.

The mammalian preimplantation embryo: Its role in the environmental programming of postnatal health and performance

“…Although an increased body weight gain during postnatal life has been reported in IVEPderived cattle (Table 1), some studies did not find this feature (Jacobsen et al, 2003;Bonilla et al, 2014). The available evidence also indicates that physiological, haematological, and biochemical profiles do not seem to be substantially affected during postnatal life in calves produced via IVEP (Jacobsen et al, 2000a;Sangild et al, 2000;Bertolini et al, 2004;Rérat et al, 2005;Givens et al, 2006;Rasmussen et al, 2013;Lopes et al, 2022;Saito et al, 2022). Similarly, calves produced by SCNT seem to have a similar growth trajectory when compared with animals produced by AI or natural breeding (Wells et al, 2004;Tian et al, 2005;Yonai et al, 2005;Watanabe and Nagai, 2008;Konishi et al, 2011;Wang et al, 2011).…”

Post-fertilization transcription initiation in an ancestral LTR retrotransposon drives lineage-specific genomic imprinting ofZDBF2

“…Briefly, presumptive IVF zygotes were denuded by pipetting after 12 h of incubation and cultured up to the blastocyst stage in mSOFai medium at 38.5 °C in a humidified atmosphere of 5% CO 2 and 5% O 2 in air for 8 days (D8). D8 blastocysts were further cultured on agarose gel for 4 dayss as described previously (Akizawa et al 2018; Saito et al 2022). The embryo proper (embryonic disc: ED) and TE portions of IVF D12 embryos were mechanically divided using a microfeather blade (Feather Safety Razor, Japan) under a stereomicroscope.…”

Post-fertilization transcription initiation in an ancestral LTR retrotransposon drives lineage-specific genomic imprinting of ZDBF2

“…Briefly, presumptive IVF zygotes were denuded by pipetting after 12 h of incubation and cultured up to the blastocyst stage in mSOFai medium at 38.5 °C in a humidified atmosphere of 5% CO 2 and 5% O 2 in air for 8 days (D8). D8 blastocysts further cultured on agarose gel for 4 dayss as described previously (Akizawa et al 2018 ;Saito et al 2022 ). The embryo proper (embryonic disc: ED) and TE portions of IVF D12 embryos were mechanically divided using a microfeather blade (Feather Safety Razor, Japan) under a stereomicroscope.…”