THE EFFECT OF CULTURE MEDIUM VOLUME ON IN VITRO DEVELOPMENT OF MOUSE EMBRYOS

Background: In the field of mammalian embryo culture, the putative influence of autocrine/ paracrine factor(s), produce by the embryos itself, is under investigation. A smaller medium drop can prevent dilution of this factor(s). Objective: The objective of this study was to examine the effect of culture medium volume on in vitro development of mouse 2-cell embryos. Materials and Methods: The embryos were obtained from female NMRI mice. To evaluate the effect of medium volume, groups of 16-20 late 2-cell embryos were cultured in 2, 5, 10, 20, 50 and 100 µl of drops of Ham's F10 medium for 72 h. Results: Development to blastocyst stage in 50 and 100 µl of drop were significantly higher than this in any other volume (p<0.001). Almost a similar pattern was also observed for hatched blastocyst formation. However, the total number of cells in blastocysts, developing in different volumes, were not significantly different. Conclusion: These results indicate that the optimal volumes of Ham's F10 medium for mouse early embryo development are 50 to 100 µl. However, volumes as small as 2 µl can successfully support mouse 2-cell embryo development to blastocyst and hatching stages.