The objective of this study was to examine the effect of various discontinuous Percoll washing conditions on motile sperm recovery rate and motion kinematics. Frozen semen samples from 3 bulls (0.5 ml plastic straws, 6% glycerol in egg yolk-Tris-glycerol extender) were thawed in 37℃ water bath for 1 min. After thawing, the mixed semen samples were randomly allocated to 12 treatment groups. Briefly, the spermatozoa were centrifuged for three different time lengths (10, 20, and 30 min) at two gravities (300×g and 700×g) through two concentrations of discontinuous Percoll density gradient of 1 ml 90%: 1 ml 45% Percoll and 2 ml 90%: 2 ml 45% Percoll to remove extender, debris, and dead spermatozoa. Motile sperm recovery rate and motion kinematics were evaluated by computer assisted sperm analyzer using Makler counting chamber. Sperm motility (%) and motile sperm recovery rate showed similar pattern in all treatment groups. However, sperm motility (%) and motile sperm recovery rate were highest at 700×g for 30 min through a discontionous Percoll density gradient of 1 ml 90%: 1 ml 45% Percoll. There were no significant differences in motion kinematics after various Percoll washings. These results suggest that force of centrifugation, centrifugation time, and Percoll volume significantly affect motile sperm recovery rate.

한우의 유전자원을 보존하기 위하여 정액동결 시험을 수행하였으며 고급육계통은 육질에 대한 육종가 상위 10% 이내의 자손에서 선발하였고 다 유계통은 어미의 이유시 체중에 대한 육종가 상위 10%이내의 자손에서 선발하였으며 2개 계통에서 종모우 총 13두를 선발하여 공시하였다. 정액채취는 인공질법으로 실시하였고 의빈대에 수소를 계류하고 채정대상우를 승가시켰으며, 3회 가승가후에 채정하였다. 채정후 10분 이내에 실험실로 옮겨와 검사항목을 조사하고 37에서