Cinematographic analysis of bovine embryo development in serum-free oviduct-conditioned medium.
Development of bovine embryos produced in vitro from the one-cell to the blastocyst stage in serum-free oviduct-conditioned medium was investigated for 8 days consecutively by time-lapse cinematography. Three movies were analysed (130 embryos). The following observations were made. (1) Development under cine-recording conditions was similar to that in a classical incubator. (2) The highest proportion of embryos at the two-cell, three-four-cell, five-eight-cell, 9-16-cell, morula and blastocyst stages were recorded at 34, 46, 61, 115, 149 and 192 h after insemination, respectively. Cleavage asynchrony between blastomeres within individual embryos started at the two-cell stage. (3) The duration of the first three cell cycles was 35 h, 14 h and 11-62 h, respectively. (4) Detailed analysis of 13 embryos revealed that developmental arrest ('Lag-phase') occurred at the four-cell (1 of 13), five-cell (2 of 13), six-cell (3 of 13), seven-cell (3 of 13) or eight-cell stage (4 of 13); this phase lasted about 59 h. Embryos arrested at the eight-cell stage developed into morula-blastocysts (3 of 4) at a higher rate than did those arrested at earlier stages (2 of 9). (5) The faster the embryos cleaved into early stages (two-cell, three-four-cell and five-eight-cell), the higher the probability that they developed into morula-blastocyst: 70% of the embryos reaching the two-cell stage before 30-31 h after insemination developed into morula-blastocyst.(ABSTRACT TRUNCATED AT 250 WORDS)
Grisart
B
B
Université Catholique de Louvain, Unité des Sciences Vétérinaires, Louvain-la-Neuve, Belgium.
Massip
A
A
Dessy
F
F
D000818:Animals; D001755:Blastocyst / Q000166:cytology; D002417:Cattle / Q000502:physiology*; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D005314:Embryonic and Fetal Development / Q000502:physiology*; D005187:Fallopian Tubes / Q000502:physiology*; D005260:Female; D009028:Morula / Q000166:cytology; D009040:Motion Pictures
D017077:Culture Media, Conditioned