40 TREATMENT OF DONOR CELLS AND ITS EFFECT ON INTERSPECIES NUCLEAR TRANSFER

Abstract

The present study was undertaken to examine the effect of donor cells, under a variety of treatment effects, on the development of goral porcine reconstructed embryos. Three experiments were performed, each with a one-way completely randomized design involving 3 to 4 replicates of all. Least significant difference (LSD) was used to determine variation among treatment groups. Experiment I focused on the effects of cycling, serum-starved (SS), and fully confluent stages of goral cells when reconstructed with porcine enucleated oocytes. In Experiment II, the effects of 2 antioxidants, β-mercaptoethanol (β-ME, 10 µM) and cysteine (2 mM), were examined after cells were fully confluent without serum starvation for 4 h. In Experiment III, the effect of different levels of dimethylsulfoxide (DMSO) at 0%, 0.5%, and 1.0% were tested, after 4 h of treatment, on the development rate after reconstruction with enucleated porcine oocytes. From the results, it appears that there were no significant (P > 0.05) differences from cleavage to morula among cyclic, SS, and fully confluent stages of the cell cycle. None of the treated group reached the blastocyst stage. There were no significant differences at the fused, 2- to 4-cell, and morula stages of embryo development after treatment of the donor cells with β-ME and cysteine before nuclear transfer. However, in the case of 8- to 16-cell stages, there were significant differences between β-ME and cysteine; the donor cells treated with β-ME had a better development rate than those treated with cysteine. No significant differences were observed in fusion, 2- to 4-cell, 8- to 16-cell, blastocyst, and hatching blastocyst stages at the 0.0, 0.5, and 1.0% levels of DMSO. However, there were statistically significant (P < 0.05) differences observed at the morula stage of embryo development. When donor cells were treated for 4 h with 0.5 and 1.0% levels of DMSO, goral-porcine reconstructed embryos reached the morula stage. From the results it can be concluded that goral somatic cells can be de-differentiated in porcine oocytes after treated with antioxidants and DMSO.