Otro
Use of strontium in the activation of bovine oocytes reconstructed by somatic cell nuclear transfer
Registro en:
Zygote. New York: Cambridge Univ Press, v. 13, n. 4, p. 295-302, 2005.
0967-1994
10.1017/S0967199405003333
WOS:000234502200003
WOS000234502200003.pdf
Autor
Yamazaki, W.
Ferreira, C. R.
Meo, S. C.
Leal, CLV
Meirelles, F. V.
Garcia, J. M.
Resumen
As an important step in the nuclear transfer (NT) procedure, we evaluated the effect of three different treatments for oocyte activation on the in vitro and in vivo developmental capacity of bovine reconstructed embryos: (1) strontium, which has been successfully used in mice but not yet tested in cattle; (2) ionomycin and 6-dimethylammopurine (6-DMAP), a standard treatment used in cattle; (3) ionomycin and strontium, in place of 6-DMAP. As regards NT blastocyst development, no difference was observed when strontium (20.1%) or ionomycin/6-DMAP (14.4%) were used. However, when 6-DMAP was substituted by strontium (3), the blastocyst rate (34.8%) was superior to that in the other activation groups (p < 0.05). Results of in vivo development showed the possibility of pregnancies when NT embryos activated in strontium were transferred to recipient cows (16.6%). A live female calf was obtained when ionomycin/strontium were used, but it died 30 days after birth. Our findings show that strontium can be used as an activation agent in bovine cloning procedures and that activation with a combination of strontium and ionomycin increased the in vitro developmental capacity of reconstructed embryos. This is the first report of a calf produced by adult somatic cell NT in Latin America.