The purpose of the study was to investigate the strength of sokinetic muscle by the position of a volleyball players. Analysis and comparison of shoulder dynamic stability will be conducted according to rotational movement of the shoulder during spiking and serving amongst the various positions. Fifty professional Korean female volleyball players (age: 20~30), all different positions – attacker (left and right), center, setter, and libero were The concentric peak torque, strength ration of the internal and external rotation of the shoulder girdle for both dominant and non-dominant arms. Firstly, there were significant differences found for the strength ratio between the setter and the other positions in the dominant arm. On a second note, there was a significant decrease in shoulder dynamic stabilization for both the attacker and center in the dominant arm. However, there were no significant differences for the setter or the libero. This study suggests that the isokinetic muscle strengths of the volleyball players are different from each other.

The objective of the current study was to describe in vitro embryo production in Hanwoo, analyzing oocytes yield and embryo production. The effects of oocytes production and the number of OPU procedures per animal on embryo production were also evaluated. OPU was done every 3～4 days during experimental period and collected oocytes were fertilized in vitro in both OPU and needle puncture groups. First, we compared the recovery rate of oocytes based on OPU session (Experiment 1). The average of collected oocytes was calculated from every 10 session. The average number of total oocytes recovered per animalonsessionwas 5.16 (mean). Second, we compared the recovery rate base on collection period of OPU (Experiment 2). The following results show the difference of the number of recovered oocytes in every month during the procedure between the months of session. Every animal shows the constant number of recovered oocytes for the first 5 months. However, the recovery rate of oocytes was decreased from month 6 to 8. Third, we compared the developmental rate to blastocyst in two groups (Experiment 3). Oocytes by needle puncture were fertilized with frozen-thawing semen; the cleavage rate 24～48 h after in vitro fertilization (IVF) was 75.8% and blastocyst development rate was 18.8% in needle puncture group. Even though there is lower cleavage rate after IVF in OPU group (61.1%), blastocyst development rate was higher compared with needle puncture group (28.4%). In conclusion, Blastocyst developmental rate could be increased by OPU than classical method of needle puncture. Improvement of bio- technique in collecting oocytes could be applied to understand the reproductive physiology in cattle, expecially Hanwoo. Therefore, further investigation should be done to clarify the efficiency and advantage of OPU involved in reproduction in animals and human being.

The objective of this study was to evaluate in vitro production of bovine embryos in Hanwoo. Oocytes were collected by ovum pick up (OPU) from ovaries of genetically high-value Hanwoo or by needle puncture from ovaries of slaughtered cattle. OPU was done every 3 4 days duing experimental period and collected oocytes were fertilized in vitro in both OPU and needle puncture groups. First, We compared the in vitro maturation rate in two groups (Experiment 1). 545 oocytes were recoverd from 4 females by 32 trials of OPU and then 433 oocytes were shown MⅡ stage after in vitro maturation (79.4%). In case of needle puncture group, 1905 oocytes were collected and then 1420 oocytes were matured to MⅡ stage during in vitro culture(74.5%). Second, we compared the developmental rate to blastocyst in two groups (Experiment 2). 1420 oocyte by needle puncture were fertilized with frozen-thawing semen; the cleavage rate 24 48 h after in vitro fertilization (IVF) was 88.6% and blastocyst development rate was 20.5% in needle puncture group. Even though there is lower cleavage rate after IVF in OPU group (84.8%), blastocyst development rate was higher compared with needle puncture group (26.4%). In conclusion, Blastocyst developmental rate could be increased by OPU than classical method of needle puncture. Improvement of bio-technique in collecting oocytes could be applied to understand the reproductive physiology in cattle, expecially Hanwoo. Therefore, further investigation should be done to clarify the efficiency and advantage of OPU involved in reproduction in animals and human being. This research was suppoted by Imsil-gun agricultural technology service center.