Embryo development rates after transfer of oocytes matured in vivo, in vitro, or within oviducts of mares

• Published in: Theriogenology Vol. 55; no. 3; pp. 705 - 715
• Main Authors: Scott, T.J., Carnevale, E.M., Maclellan, L.J., Scoggin, C.F., Squires, E.L.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.02.2001
• Subjects: Animals; Embryonic and Fetal Development - physiology; equine; Fallopian Tubes - physiology; Female; Gamete Intrafallopian Transfer - veterinary; GIFT; Horses - physiology; In Vitro Techniques; Oocyte Donation - veterinary; oocyte maturation; oocyte transfer; Oocytes - transplantation; Pregnancy; Tissue and Organ Harvesting - methods; Tissue and Organ Harvesting - veterinary; TVA; GIFT; oocyte maturation; oocyte transfer; TVA; equine
• ISSN: 0093-691X; 1879-3231
• DOI: 10.1016/S0093-691X(01)00438-1

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) immature 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.