ASSESSMENT OF NUCLEAR MATURATION AND OOCYTE VIABILITY IN NORMAL AND REPEAT BREEDER CROSSBRED COWS BY USING FLUORESCENT STAINING

The study was carried out in 12 normal and 12 repeat breeder crossbred cows. These cows were further divided into four groups of six animals in each group. The animals were subjected to transvaginal oocyte recovery (TVOR) for a period of twomonths without any treatment at once weekly and twice weekly interval. Culture grade oocytes retrieved were subjected to in vitro maturation for 24hat 38.5o C and 5 per cent CO2 . Nuclear maturation was assessed with Hoechst 33342 stain and oocyte viability was assessed with fluorescein diacetate (FDA) stain. Results revealed that nuclear maturation based on Hoechst 33342 as 80.00 and 76.19 per cent respectively for normal and repeat breeders. Assessment ofviability of oocytes based on fluorescein diacetate (FDA) stain revealed that viability of oocytes in normal breeders (83.33 per cent) was higher than repeat breeiders (75 per cent). The present study revealed that nuclear maturation rate and oocyte viability is less in repeat breeders when compared to normal breeders.