Effect of Different Activation Techniques on Immature and In Vitro Matured Cat Oocytes

Abstract

This study was conducted to determine the most successful techniques on inmature and in vitro-matured cat oocytes that were parhtenogenically activated using 6-dimethylaminopurine (6-DMAP) and cycloheximide (CHX), in combination with electrical stimulation and calcium ionophore. After 44 h of in vitro maturation, the oocytes with a polar body were separated as mature (M II) and those without a polar body were considered as immature. Four different activation treatments and two control groups were used for parthenogenetic activation with both mature and immature cat oocytes. After 48 h of activation, the oocytes were examined and the non-cleaved oocytes removed. The cleaved oocytes/embryos were cultured in vitro in mSOF medium for an additional four days. After six days of in vitro culture (IVC), embryo quality was evaluated. The results in the present study suggested that (I) both in vitro matured and immature cat oocytes have a potential to develop to morula and blastocyst stages after parthenogenetic activation, (II) electrical stimulation + 6-DMAP is a more useful technique for both matured and immature cat oocytes and (III) to our knowledge, this is the first report that describes morula and blastocyst formation from parthenogenetically activated immature cat oocytes.