ESTABLISHED CELL-LINES AND THEIR CONDITIONED MEDIA SUPPORT BOVINE EMBRYO DEVELOPMENT DURING IN-VITRO CULTURE

These experiments were conducted to evaluate the ability of different somatic-cell monolayers or conditioned medium from somatic cells for s upporting bovine embryo development in vitro. In the first experiment, bovine embryos (2- to 4-cells) were allocated randomly to a control ( medium 199 with 10% fetal bovine serum and antibiotics) group or co-cu ltured with bovine oviduct epithelial (BOEC), buffalo rat liver (BRL), Madin Darby bovine kidney (MDBK)) or African green monkey kidney (Ver o) cells. In the second experiment, bovine embryos (1-cell) were alloc ated randomly to the following groups: control medium or conditioned m edium from BOEC, BRL, MDBK and Vero monolayers. In both experiments, d evelopment to the blastocyst stage was assessed after 8 days of incuba tion at 39 degrees C and 5% CO2. In Experiment 1, co-culture improved development to the blastocyst stage compared with control medium atone , and the highest development was observed after co-culture with BOEC. In Experiment 2, conditioned medium enhanced development to morulae a nd blastocysts compared with the control medium; however, no differenc es were detected among different cell supports. These results indicate that both coculture and conditioned medium from different cell monola yers supported development to the blastocyst stage at a higher efficie ncy than control medium alone.