In vitro and in vivo development of embryos produced by in vitro maturation and in vitro fertilization of cat oocytes.
Cumulus-oocyte complexes of domestic cats were classified by morphology of ooplasm (A = good, B = fair, C = poor) and cultured for 24 h in TCM 199 with gonadotrophins (eCG, FSH, hCG or FSH/hCG). More of type A oocytes (52%) underwent in vitro maturation (IVM) than of type B (41%) or type C (17%). The gonadotrophin source did not affect frequency of IVM of type A (50-53%) or type B (38-44%) oocytes, but IVM of type C oocytes in hCG or FSH/hCG (27%/19%) was about double that in eCG or FSH alone (13%/10%). After IVF, frequency of cleavage for type A (54%), B (41%) and C (26%) oocytes was similar to the IVM frequency of the equivalent type. After 7 days, development to the morula (M) stage in vitro was similar among types (47-58%); however, higher percentages of type A and B oocytes developed to blastocysts (Bl), 31% and 29%, respectively, than of type C (15%). After transfer of day 5 (n = 70) or 6 (n = 32) M and Bl to day 4 or 5 recipients in trial 1 (n = 4) and 2 (n = 3), respectively, the three recipients in trial 2 gave birth to four live kittens. Development in vitro to M of IVM/IVF embryos frozen in propanediol plus sucrose during early cleavage was similar (64-69%) to that of cohort controls (64%), but Bl formation was reduced (13-17% versus 32%). Damage to the zona pellucida after plunging into liquid nitrogen at -30 degrees C was higher (11%) than that of the embryos cooled at 10 degrees C min-1 from -30 degrees C to -150 degrees C before storage (2%).
Pope
C E
CE
Center for Reproduction of Endangered Wildlife, Cincinnati Zoo, OH 45220, USA.
McRae
M A
MA
Plair
B L
BL
Keller
G L
GL
Dresser
B L
BL
D000818:Animals; D002415:Cats; D002470:Cell Survival; D002478:Cells, Cultured; D015925:Cryopreservation; D003470:Culture Media; D004624:Embryo Transfer / Q000662:veterinary; D004622:Embryo, Mammalian / Q000502:physiology; D005314:Embryonic and Fetal Development; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods / Q000662:veterinary*; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D006064:Gonadotropins, Equine / Q000494:pharmacology; D008297:Male; D009865:Oocytes / Q000166:cytology* / Q000502:physiology; D009866:Oogenesis; D011247:Pregnancy; D012099:Reproductive Techniques
D003470:Culture Media; D006064:Gonadotropins, Equine; D005640:Follicle Stimulating Hormone