This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.
Bovine oviduct and uterine fluid support in vitro embryo development
In order to mimic the maternal oviductal environment, we evaluated the effect of oviductal fluid (OF) and/or uterine fluid (UF) supplementation on in vitro embryo development and quality. In vitro produced zygotes were cultured with 1.25% OF from Day 1 to 4 and/or with 1.25% UF from Day 4 to 9 post insemination. Synthetic oviduct fluid (SOF) supplemented with 3 mg/ml bovine serum albumin (BSA) or 5% fetal calf serum (FCS) were used as control groups. Oviductal fluid and/or UF at 1.25% supported embryo development (Day 9 range: 28.2%-30.6%). At 72 h after vitrification/warming, blastocysts obtained from OF and OF+UF groups survived at a similar rate to those from SOF+BSA (61.0±5.7% 62.8±6.4%, 64.8±6.4%, respectively), but at a rate significantly higher than those from SOF+FCS (31.6±4.9%)(P<0.001). Furthermore, blastocysts from OF displayed up-regulation of DNMT3A and IGF2R (epigenetic genes), while those from OF+UF and UF exhibited a down regulation of GPX1 and CLIC1 (oxidative stress genes), in comparison with SOF+FCS (P<0.05). A lower accumulation of reactive oxygen species (ROS) was observed in blastocysts from OF and/or UF groups. In conclusion, the use of low concentrations of OF and UF in in vitro serum-free culture supports embryo development with OF providing a better control of embryo methylation while UF may have an antioxidant activity.
RD17286 Accepted 20 October 2017
© CSIRO 2017