Supplementation with glucose in PZM-3 medium improve the in vitro development of porcine transgenic cloned embryos

The efficiency of producing porcine transgenic cloned embryos is still low due to lower developmental competence compared to in vivo-fertilized/cultured embryos. This phenomenon may correlates with poor culture condition. Energy substrate in culture medium play an important role in optimizing culture condition. This study pertain to investigate the effect of replacing pyruvate and lactate with glucose in PZM-3 medium at the rest part culture period on porcine embryonic development after SCNT. Porcine adult fibroblasts cells were transfected with pEGFP-C1 vector. Then transfected cells were used as donor cells for producing re-constructed embryos. Results have shown that supplement of glucose up to 5mM concentration in PZM-3 at the rest part of culture period improved the development of transgenic cloned embryos. Moreover, supplement of glucose(5mM) as energy substrate in PZM-3 at 48h of culture was optimal time. However, with regard to the percentage of EGFP-positive blastocyst, there was no significant difference between treatments. In conclusion, replacing pyruvate and lactate with glucose in PZM-3 medium at the rest part of culture period was beneficial to the development of transgenic cloned embryos and had no effect on transgene expression.