Effect of addition of butaphosphan to the medium of oocyte maturation in the production of in vitro bovine embryos

The quality of the oocyte maturation is directly related to the embryonic development rate, as it depends on the amount of oocyte mRNA stored during this period. During maturation, the oocyte undergoes different processes that are related to phosphorylation and dephosphorylation cascades. Butaphosphan, an organic phosphorus molecule, has been administrated in embryo or oocyte donor cows to improve the results of the assisted reproductive technology programs. Therefore, our hypothesis in this study was the one that the addition of butaphosphan to the in vitro maturation medium (IVM) could improve oocyte maturation, enlarging the production of embryos. Eight routines of IVF were performed, totalizing 800 cumulus/oocyte complex originated from slaughterhouses. Mediums of Cenatte® (Cenatte®, Pedro Leopoldo – MG – Brasil) were used to perform IVF. The oocytes were randomly divided, in each routine, into four groups of 25 oocytes and the IVM medium was supplemented with crescent doses of butaphosphan (Capot Chemical Company Limited, Hangzhou, Zhejang, China) (Gc = 0.0mg/L; G1 = 50mg/L; G2 = 100mg/L e G3 = 200mg/L). IVM took place for 24h in an incubator with 5% CO2 and temperature of 39°C. Spermatozoids were selected by the minipercoll method and 10μL with 1x106 spermatozoids/mL were used to perform IVF. After 18h, probable zygotes were transferred to the culture medium under controlled conditions (5% CO2, 5% O2, 90% N2) at 39°C for 7 days. SAS (SAS, Cary, NC, EUA) was used to perform the statistical analysis, GLM was used to verify the linear, squared and cubic effect of the addition of the crescent doses of butaphosphan to the IVM medium over the embryos percentage in D7 in relation to the number of maturated oocytes. The production of embryos in D7 as of 34.7%, 28.5%, 33.5% e 31.6% in the groups Gc, G1, G2 and G3 respectively, there was no effect of the group (P>0.05). Our data showed that the addition of butaphosphan to the IVM medium does not interfere directly on oocyte maturation, as it did not affect the production of in vitro bovine embryos.