title: Transfer of split goat embryos without zonae pellucidae either fresh or after freezing.
abstract: Embryos in the morula to blastocyst stage were collected from superovulated goats either surgically or after slaughter. Embryos with good or fair morphology were bisected with a microblade without the aid of a holding pipette or other microinstruments. Of 103 morulae and 77 blastocysts that were split, 200 (97%) and 151 (98%) demi-embryos, respectively, with no major morphological aberrations were obtained. Zona-free demi-embryos derived from blastocysts were incubated in vitro for 2 h, and those derived from morulae for 24 h so that they would reach the blastocyst stage. Demi-embryos were transferred either fresh or after freezing and thawing. After 2 h of incubation, a significantly higher proportion of zona-free demi-embryos derived from blastocysts were of good quality than were zona-free demi- embryos derived from morulae (75 vs 45%). Seventy-six percent of zona-free demi-embryos derived from morulae developed to the blastocyst stage after 24 h in vitro. The quality of the embryos before splitting had a significant effect on the development of the demi-embryos in vitro. Transfer of 11 pairs of zona-free demi-embryos resulted in the birth of five twin and three singleton kids. Transfer of 11 pairs of demi-embryos frozen-thawed without zonae pellucidae resulted in the delivery of two singleton kids.
authors.affiliation: Institute of Animal Husbandry and Genetics, University of Goettingen, FRG.
authors.forename: M A
authors.initials: MA
authors.lastname: Nowshari
authors.forename: W
authors.initials: W
authors.lastname: Holtz
mesh_terms: D000818:Animals; D001755:Blastocyst; D015925:Cryopreservation / Q000662:veterinary*; D004624:Embryo Transfer / Q000662:veterinary*; D005260:Female; D005615:Freezing; D006041:Goats / Q000196:embryology*; D008297:Male; D009028:Morula; D011247:Pregnancy; D015044:Zona Pellucida