title: Development of cloned pig embryos by nuclear transfer following different activation treatments.
abstract: 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 musec). Oocytes were pulsed thrice electrically with 1.4 kV/cm for 20 musec and NT eggs were divided into three treatment groups: Group 1 (no further treatment), Group 2 (10 mug/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 muL 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, approximately 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.
authors.affiliation: College of Veterinary Medicine, Gyeongsang National University, Chinju, Republic of Korea 660-701.
authors.forename: Yang-Sil
authors.initials: YS
authors.lastname: Kim
authors.forename: Sung-Lim
authors.initials: SL
authors.lastname: Lee
authors.forename: Sun-A
authors.initials: SA
authors.lastname: Ock
authors.forename: S
authors.initials: S
authors.lastname: Balasubramanian
authors.forename: Sang-Young
authors.initials: SY
authors.lastname: Choe
authors.forename: Gyu-Jin
authors.initials: GJ
authors.lastname: Rho
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D019976:Cloning, Organism / Q000662:veterinary*; D003513:Cycloheximide / Q000494:pharmacology; D020732:Cytogenetic Analysis; D047108:Embryonic Development / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D005260:Female; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000166:cytology; D011003:Ploidies; D011725:Pyridines / Q000494:pharmacology; D034421:Sus scrofa / Q000196:embryology* / Q000235:genetics
chemical_list: C417980:4-(dimethylamine)pyridine; D011725:Pyridines; D003513:Cycloheximide