Survival and viability of fresh and frozen-thawed in vitro bovine blastocysts.
Three experiments were undertaken to investigate the effect of some factors on survival and viability of bovine blastocysts produced in vitro in serum-free oviduct-conditioned media. In vitro survival to freezing was higher for blastocysts appearing on days 6 and 7 than for day 8 blastocysts (67 and 50% hatching rate vs 12%). Transfer success of day 8 blastocysts to recipient heifers was 35% (9/26) calves born vs 19% (4/21) for cows. Embryo mortality occurred mainly during the peri-implantation period (between days 21 and 45) for cows compared with heifers. Calving rate after direct transfer of frozen blastocysts without dilution was 24% (4/17) compared with 31% (5/16) for control unfrozen blastocysts.
Massip
A
A
Université Catholique de Louvain, Unité Vétérinaire, Louvain-La-Neuve, Belgium.
Mermillod
P
P
Van Langendonckt
A
A
Touze
J L
JL
Dessy
F
F
D000818:Animals; D001755:Blastocyst / Q000502:physiology*; D002417:Cattle; D002478:Cells, Cultured; D015925:Cryopreservation; D003470:Culture Media; D017077:Culture Media, Conditioned; D004624:Embryo Transfer; D005187:Fallopian Tubes / Q000502:physiology; D005260:Female; D006358:Hot Temperature; D011247:Pregnancy
D003470:Culture Media; D017077:Culture Media, Conditioned