Embryo development rates after transfer of oocytes matured in vivo, in vitro, or within oviducts of mares.
Objectives of the present study were to use oocyte transfer: 1) to compare the developmental ability of oocytes collected from ovaries of live mares with those collected from slaughterhouse ovaries; and 2) to compare the viability of oocytes matured in vivo, in vitro, or within the oviduct. Oocytes were collected by transvaginal, ultrasound-guided follicular aspiration (TVA) from live mares or from slicing slaughterhouse ovaries. Four groups of oocytes were transferred into the oviducts of recipients that were inseminated: 1) oocytes matured in vivo and collected by TVA from preovulatory follicles of estrous mares 32 to 36 h after administration of hCG; 2) immature oocytes collected from diestrous mares between 5 and 10 d after aspiration/ovulation by TVA and matured in vitro for 36 to 38 h; 3) immature oocytes collected from diestrous mares between 5 and 10 d after aspiration/ovulation by TVA and transferred into a recipient's oviduct <1 h after collection; and 4) im mature oocytes collected from slaughterhouse ovaries containing a corpus luteum and matured in vitro for 36 to 38 hours. Embryo development rates were higher (P < 0.001) for oocytes matured in vivo (82%) than for oocytes matured in vitro (9%) or within the oviduct (0%). However, neither the method of maturation nor the source of oocytes affected (P > 0.1) embryo development rates after the transfer of immature oocytes.
Scott
T J
TJ
Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins 80523, USA.
Carnevale
E M
EM
Maclellan
L J
LJ
Scoggin
C F
CF
Squires
E L
EL
D000818:Animals; D005314:Embryonic and Fetal Development / Q000502:physiology*; D005187:Fallopian Tubes / Q000502:physiology*; D005260:Female; D015181:Gamete Intrafallopian Transfer / Q000662:veterinary; D006736:Horses / Q000502:physiology*; D066298:In Vitro Techniques; D018587:Oocyte Donation / Q000662:veterinary; D009865:Oocytes / Q000637:transplantation*; D011247:Pregnancy; D020858:Tissue and Organ Harvesting / Q000379:methods / Q000662:veterinary