한우 체외수정란 생산을 위한 ${\alpha}$-Tocopherol 첨가와 동결 효과

Effect of ${\alpha}$-Tocopherol Treatment and Freezing for In Vitro Bovine Embryo Production in Korean Native Cows

본 연구는 한우의 체외수정란 생산에서 체외성숙, 체외 배양시 배양액에 항산화제인 ${\alpha}$-Tocopherol의 첨가 농도에 따른 대조구와 처리구 난포란의 발달과 배반포 발생율 및 초자화 동결 후 생존성에 미치는 영향을 구명하고자 실험을 실시하였다. ${\alpha}$-Tocopherol 첨가 농도에 따른 분할율에서는 7~10월까지 비교한 결과, ${\alpha}$-tocopherol 200 ${\mu}M$ 첨가된 처리구가 대조구 및 타 처리구보다 높은 경향을 보였으나, 유의적 차이는 없었다. 배반포 발생율에서는 8~10월에서 ${\alpha}$-tocopherol 200 ${\mu}M$ 첨가된 처리구 $38.60{\pm}7.12%$가 대조구 및 타 처리구들보다 유의적으로 높게 (p<0.05) 나타났다. 초자화 동결 전 후의 총세포수는 ${\alpha}$-tocopherol 200 ${\mu}M$ 처리구에서 $115.80{\pm}6.61$개, $106.33{\pm}3.50$개로서, 다른 대조구 및 타 처리구보다 높은 세포수를 보였다. 월별에 따른 수정란의 배반포 발생율 및 동결 전후의 총세포수에서는 7~8월이 9~10월보다 유의적으로 높게 (p<0.05) 나타났다.

The aim of this study was to evaluate the effect of ${\alpha}$-tocopherol on blastocysts development and subsequent cryosurvival of the vitrification. The ${\alpha}$-tocopherol(0, 100, 200, 400 ${\mu}M$) was added in to culture medium for the bovine embryos. The blasocysts from the ${\alpha}$-tocopherol and untreated control groups were then frozen-thawed, and their cryosurvival was assessed by in vitro culture for 48 h. There were no differences in the overall cleavage rate($56.14{\pm}4.66$, $58.18{\pm}4.70$, $62.97{\pm}6.86$ and $51.17{\pm}7.28$) among four treatment groups. However, in blastocyst development and total cell number were significantly higher in ${\alpha}$-tocopherol 200 ${\mu}M$ ($38.60{\pm}7.12$; $106.33{\pm}3.50$) to culture medium than other treatment groups($29.30{\pm}5.24$, $31.60{\pm}7.12$ and $26.37{\pm}4.18$; $101.36{\pm}5.12$, $97.27{\pm}2.87$, and $91.23{\pm}7.52$ respectively). Before and after vitrification, the total cell number and blastocyst development of embryo were significantly higher in July to August than September to October. In conclusion, addition of ${\alpha}$-tocopherol 200 ${\mu}M$ to in vitro bovine embryo culture medium was beneficial for improving embryo quality by decreasing the embryo damage blsstocysts cell number and improving the tolerance of the embryos to cryopreservation.