The effects of pre and post vitrification taxol treatment on bovine immature oocyte

The aim of the present study was to find the effects of pre and post vitrification taxol treatment on bovine immature cumulus oocyte complexes (COCs). Bovine ovaries were collected from the local slaughterhouse in a container with 30-37°C physiologic saline and supplemented with antibiotics. The grade A aspirated COCs were assigned to 6 experimental groups; The 1st group was control (n=100) in which the COCs were subjected to in vitro maturation (IVM) in oocyte maturation medium (OMM). The 2nd group was the COCs (n=51) that were exposed to vitrification and warming solutions and then subjected to IVM. The 3rd group was the COCs which were incubated in OMM contained taxol (1 μM، n=51) for 20 min then transferred to IVM. The 4th group was the COCs (n=50) that were vitrified، warmed and transferred to IVM. The 5th group (n=57) was the COCs which were incubated in OMM containing taxol (1 μM for 20 min)، vitrified (solutions with 1 μM taxol)، warmed and transferred to IVM. The last group was the COCs (n=58) that were vitrified and warmed، then were incubated in maturation medium containing taxol (1 μM for 20) and، finally، were transferred to IVM. The COCs of all groups were incubated in OMM for 24 h under a humified (95%) condition with a temperature of 39°C and 5% CO2. Oocyte maturation was not affected by exposing the COCs to vitrification solution or taxol groups compared to control (P>0. 05). Vitrification reduced the oocyte maturation rate compared to control (P<0. 05). Taxol treatment (before and after vitrification) did not improve the bovine oocyte maturation rate compared to control (P<0. 05). The results have shown no beneficial effect of taxol on vitrification of bovine immature oocytes.