The effectiveness of human SAGE medium compared to other conventional culture media on the ovine early embryonic development, in vitro

Abstract

Developing an optimal in vitro embryo culture medium with high blastocyst rates and good-quality embryos remains challenging and controversial, as most culture media directly impact mammalian embryonic development. This study aims to identify the most suitable culture medium for ovine embryo development based on its impact on embryo quality and developmental rates. Ewes’ ovaries (n=250) were collected from a local abattoir and transported at 4°C to the laboratory. Oocytes from follicles (3-5 mm) were aspirated. In vitro maturation was performed in a 500 μl TCM-199 medium and then incubated for 24 h. The sperm cells were collected from fresh testes-epididymides, then the oocytes were fertilized with sperm concentrations of 7x106/ml. Five embryo culture media were tested to compare embryo quality and development rates. Zygotes were cultured in a synthetic oviductal fluid medium as a control group, Medium 199, Bracket and Oliphant’s medium, the bee honey culture medium, or SAGE 1-Step™ medium for seven days. The SAGE medium dramatically raised the embryos' quality compared to their counterparts cultured in synthetic oviductal fluid, medium 199, Bracket and Oliphant, or bee honey medium. In addition, the SAGE medium considerably outperformed the other media regarding embryo compaction rate on day 3. In summary, the rates and speed of embryonic development in ovine varied depending on the culture media used. The availability of glucose and growth factors provided by the culture media influenced the quality and rates of ovine blastocysts.