Abstract
To investigate the maturational and development competece of porcine oocytes of different diameter groups, oocytes were obtained by aspiration from slaughterdhouse ovaries. After washing three times in NCSU23 medium, each cumulus-oocyte complex was transferred into a $8{mu}ell$ drop of the maturation medium (one oocyte per drop) under paraffin oil. The diameter without zona pellucida of oocytes was measured with micor-calibrator (Mikrometer, E. Leitz) on a screen connected to a VCR on an inverted microscope $(200\times)$. After being measured, the oocytes were divided into 6 groups according to their diameter size : <105, 105 to < 110, 110 to < 115, 115 to < 120, 120 to < 125 and > $125{\mu}{\textrm}{m}$, and in vitro maturation (IVM), fertillzation (IVF) and production (IVP) of oocytes / embryo was performed. The rates of in vitro maturation on oocytes in the greater 105 ${\mu}{\textrm}{m}$ size groups(91.8~100%) were significantly (P<0.05) higher than in the < 105 ${\mu}{\textrm}{m}$ group(66.7%). The rates of sperm penetration were significantly (P<0.05) low in < $105{\mu}{\textrm}{m}$ group (50.0%) than others groups (81.6~85.5%). But the plyspermic fertilization rate was significantly (P<0.05) higher in < $110{\mu}{\textrm}{m}$ oocytes groups than in the $110\leq{\mu}{\textrm}{m}$ size groups. The rates of cleavage and development to blastocysts rose as oocytes diameter increased, however, while oocytes over $120{\mu}{\textrm}{m}$ in diameter failed to develop to blastocysts. There results suggest that porcine oocytes have acquired full meiotic competece at a diameter of $105{\mu}{\textrm}{m}$ but not yet attended full development competence to blastocyst and that oocytes have acquired full development competence at a diameter of $110{\mu}{\textrm}{m}$.
도축장에서 채취한 돼지난자를 직경별로 $5\mu\textrm{m}$ 간격으로 나누어, 난자의 크기에 따른 체외성숙과 발육능을 구명코자 체외성숙과 체외수정 후의 배 발달율을 조사하였다. 채취한 난자의 투명대를 제외한 평균직경은 $114.4\pm5.45\;\mu\textrm{m}$ 이었으며, 직경별 분포는 < 105, 105~110, 110~115,115~120, 120~125, $125\;\mu\textrm{m}$<이 각각 3.0, 11.0, 31.2, 41.5, 13.0 및 0.4%로 72.7%가 110부터 $120\;\mu\textrm{m}$ 사이였다. 체외성숙율에 있어서 직경 $105\;\mu\textrm{m}$ 미만난자는 66.7%인 반면 $105\;\mu\textrm{m}$ 이상의 난자는 91.8~100%로 유의적(P<0.05)으로 높았다. 체외수정율도 직경 $105\;\mu\textrm{m}$ 미만인 난자는 50% 이었던 반면, $105\;\mu\textrm{m}$이상은 8106~85.5%로 유의적(P<0.05)으로 높았다.다정자침입율에 있어서 $110\;\mu\textrm{m}$이상의 난자는 17.8~27.7%로 $105~110\mu\textrm{m}$ 의 37.5% 보다 낮았다. 난자의 직경별 배반포기까지의 발달율은 $105\;\mu\textrm{m}$ 이하는 전혀 발달하지 않았고(0%), $105~110\mu\textrm{m}$는 701%, $110~11\;5\mu\textrm{m}$ 12.5%, $115~120\; \mu\textrm{m}$ 24.0%, $120~125\; \mu\textrm{m}$ 18.3%, $120\; \mu\textrm{m}$<0%로, $115~120\; \mu\textrm{m}$ 직경난자의 체외발달율이 유의적(P<0.05)으로 높았다.이상의 결과를 종합할 때, 돼지의 체외수정용 나자는 직경 $110\; \mu\textrm{m}$ 이상을 이용하는 것이 생산성을 높일 수 있는 방법으로 사료된다.
