GROWTH AND METABOLISM OF MURINE AND BOVINE EMBRYOS IN BOVINE UTERINE FLUSHING-SUPPLEMENTED CULTURE MEDIA

The aim of this study was to compare the development and metabolic act ivity of cultured murine and bovine embryos in 2 standard media (HAM F -10 and RPMI) in the presence or absence of bovine uterine flushings, Murine morulae (n = 653) and day 7 bovine embryos (n = 273) were cultu red for 18 h or 36 h in either HAM F-10 or RPMI in the presence or abs ence of bovine uterine flushings, After culture, the development, qual ity, and metabolic activity (glucose utilization or methionine uptake and incorporation) of embryos was assessed, It was found that HAM F-10 (without uterine flushings) was a more suitable medium than RPMI for optimal development and metabolism of murine and bovine embryos, Poor quality and development, as well as decreased metabolism, were evident after culture of murine embryos in RPMI; in contrast, this medium had no adverse effects on bovine embryos in culture, Supplementation of H AM F-10 with bovine uterine flushings improved the growth of murine em bryos and the protein synthesis (as measured by an increased methionin e incorporation) for both murine and bovine embryos, However, suppleme ntation with bovine uterine flushings could not overcome deficiencies of an inappropriate medium (RPMI) for murine embryos, Supplementation of a well-defined culture medium with uterine flushings increased meta bolism of embryos in culture, and thus might help to increase pregnanc y rates after transfer of such embryos to recipient cows.