title: Effects of culture systems on development of in vitro fertilized bovine ova into blastocysts.
abstract: We examined the effects of co-culture with oviductal epithelial cells, cumulus cells, trophoblastic vesicles or amniotic sac cells on the development of bovine eight-cell embryos derived from in vitro maturation and fertilization into blastocysts. Frozen-thawed spermatozoa were treated with caffeine plus Ca-ionophore A23187 for capacitation and were then co-incubated for 4 h with oocytes matured in vitro. Ova resulting from this in vitro fertilization were cultured in HEPES-buffered TCM-199 + 10% fetal calf serum(FCS) for 68 h and then removed from the cumulus cell mass. The eight-cell embryos were cultured using four co-culture systems either without cells(controls) or within rabbit oviducts. The co-culture of oviductal epithelial cells, trophoblastic vesicles or amniotic sac cells significantly (P<0.05) increased development into blastocysts (39.0 to 50.7%) when compared with co-culture with cumulus cells, control or rabbit oviducts(1.9 to 29.3%). Six of 16 recipients became pregnant with frozen embryos derived from co-culture with oviductal epithelial cells(1/2), trophoblastic vesicles(2/7) or amniotic sac cells(3/7). Eight calves, including two sets of twins, were obtained.
authors.affiliation: Hokkaido Livestock Improvement Association Inc., Tokorogun, Hokkaido 099-14, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Aoyagi
authors.forename: Y
authors.initials: Y
authors.lastname: Fukui
authors.forename: Y
authors.initials: Y
authors.lastname: Iwazumi
authors.forename: M
authors.initials: M
authors.lastname: Urakawa
authors.forename: H
authors.initials: H
authors.lastname: Ono