Development of cloned pig embryos by nuclear transfer following different activation treatments

• Published in: Molecular reproduction and development Vol. 70; no. 3; pp. 308 - 313
• Main Authors: Kim, Yang-Sil, Lee, Sung-Lim, Ock, Sun-A, Balasubramanian, S., Choe, Sang-Young, Rho, Gyu-Jin
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.03.2005; Wiley-Liss
• Subjects: activation; Analysis of Variance; Animals; Biological and medical sciences; Cloning, Organism - veterinary; Cycloheximide - pharmacology; Cytogenetic Analysis; Embryology: invertebrates and vertebrates. Teratology; Embryonic Development - drug effects; Embryonic Development - genetics; Embryonic Development - physiology; Female; fetal fibroblasts; Fundamental and applied biological sciences. Psychology; Molecular embryology; Nuclear Transfer Techniques; Oocytes - cytology; pig oocyte; Ploidies; Pyridines - pharmacology; Sus scrofa - embryology; Sus scrofa - genetics; Animal cloning; Embryonic development; Ploidy; Cell nucleus; NT; fetal fibroblasts; Germinal cell; In vitro; Phosphorylation inhibitor; Pig; Genetic transfer; pig oocyte; Vertebrata; Mammalia; Animal; Artiodactyla; Protein synthesis inhibitor; activation; Ungulata; Oocyte
• ISSN: 1040-452X; 1098-2795
• DOI: 10.1002/mrd.20211

This study compared the effects of activation treatments on the development and ploidy of nuclear transferred (NT) pig embryos. After in vitro maturation of oocytes collected from the slaughterhouse, oocytes were enucleated and reconstructed by transfer of donor cells and fusion with three DC pulses (1.4 kV/cm, 20 μsec). Oocytes were pulsed thrice electrically with 1.4 kV/cm for 20 μsec and NT eggs were divided into three treatment groups: Group 1 (no further treatment), Group 2 (10 μg/mL cycloheximide [CHX], 3 hr), and Group 3 (1.9 mM 6‐dimethylaminopurine [DMAP], 3 hr). All the eggs were cultured in sets of 30 in 60 μL drops of NCSU‐23 supplemented with 4 mg/mL fatty acid free BSA, and compared for the rates of development and ploidy. The rates of cleavage, development, and total cell number of parthenotes in Group 3 were significantly (P < 0.05) higher than those in Groups 1 and 2. Cleavage rates of NT embryos in Group 1 were significantly (P < 0.05) lower than those in Groups 2 and 3 (73% vs. 81% and 82%, respectively). Development into blastocyst stage and total cell number of NT embryos in Group 3 were significantly (P < 0.05) higher than those in Groups 1 and 2. Although the embryos in Group 3 had higher development, ∼58% of NT embryos evaluated were abnormal ploidy (6% haploidy, 9% polyploidy, and 42% mixoploid). The results suggested that although DMAP enhanced development and higher cell number, due attention should be paid to abnormal ploidy in pig NT embryos. Mol. Reprod. Dev. 70: 308–313, 2005. © 2005 Wiley‐Liss, Inc.