Earticle

본 연구는 0.5 ml straw를 이용한 정자 동결융해 시 융해 온도가 동결정자의 성상에 미치는 영향을 파악하고 미니 돼지의 동결정액에 최적화된 적정 융해 조건을 찾기 위하여 실시하였다. 정액동결 straw를 37, 50 및 70℃에서 각각 5초, 10초 및 45초간 융해하여 생존율(SYBR-14/PI staining), 정자원형질막기능검사 (Hypoosmotic Swelling Test) 및 첨체반응율 (CTC : chlorotetracycline staining)을 검사 한 결과 70℃에서 5초간 융해한 정자의 생존율과 CTC 결과가 37℃와 50℃에서 10초 및 45초간 융해한 처리구보다 유의적(p<0.05)으로 높은 생존율과 낮은 비율의 첨체 반응율을 얻었다. 따라서 미니 돼지의 동결 정액은 고온에서 단시간 융해를 하는 것이 정자의 성상에 유리한 것으로 사료된다.

The objective of this study was to investigate the effect of thawing temperature on the sperm viability and acrosomal morphology for semen storage of miniature pig by the 0.5 ml straw method. In this present study, sperm viability (SYBR-14/PI staining), membrane integrity (Hypoosmotic Swelling Test), acrosome intactness, intensity and capacitation status (chlorotetracycline staining) in frozen miniature pig sperm were evaluated after thawing at 37, 50 and 70℃ for 5, 10 and 45 sec, respectively. Interestingly, the results indicated that sperm thawed at 70℃ for 5 sec significantly (p<0.05) increased sperm viability, but lower the percentage of AR (acrosome reacted spermatozoa) pattern compared to sperm thawed at 37℃ for 45 sec and 50℃ for 10 sec. In terms of thawing condition, high temperature for a short time using the 0.5 ml straw was improved cryosurvival of miniature pig semen. Therefore, appropriate thawing method for cryopreservation of miniature pig is required for increasing post-thawing viability.

The purpose of this study was to assess sperm quality during in vitro storage of miniature-pig semen in order to determine which extender should be used and how extender can be diluted for in vitro storage of miniature-pig semen. Freshly ejaculated miniature-pig's semen was diluted with same volumes of Beltsville Thawing Solution (BTS), Androhep, Modena, Mulberry III and modified-Modena extenders. Sperm quality was evaluated by examining viability, motility, abnormality, acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining. Sperm motility decreased with storage period prolonged and differences among BTS, Androhep, Modena and Mulberry III were apparent On Day 1, approximately 80% of the sperm were motile, but motility decreased to 40% at Day 7. During the 7 days of storage, sperm survival in modified-Modena B extender was higher than another extenders. However, it was not differ significantly among other extenders. The percentage of F and B patterns were not differ significantly among the extenders. However, F pattern in modified-Modena B extender was slightly higher until 3 days of storage than that of Modena extender, modified-Modena A extender and modified-Modena C extender. The percentage of AR patterns in modified-Modena B extender was slightly lower, but did not differ significantly among other extenders. The results of present study suggest that modified-Modena B was effective as new extender for in vitro storage of miniature-pig semen.

The present study was conducted to assess sperm characteristics in miniature-pig. The semen samples were transported to the laboratory at 17℃ within 3 hours after collection. The extended semen was stored at 17℃, and sperm quality was evaluated at 0, 1, 3, 5 and 7 days after storage. The semen volume of miniature-pig (62±22㎖) was significantly (p<0.05) lower than that of Duroc (155±25㎖) and Yorkshire (154±23㎖). Significant differences were also observed in sperm concentrations. During 3 days of storage, sperm viability did not differ among miniature-pig, Duroc and Yorkshire. However, the viability was significantly (p<0.05) lower in miniature-pig than in Duroc and Yorkshire semen after Day 3 of storage. In abnormality, acrosome intactness and intensity, there were no differences among miniature-pig, Duroc and Yorkshire semen. On the other hand, the viability of frozen-thawed sperm in miniature-pig was significantly (p<0.05) lower than in that of Duroc and Yorkshire. This study also examined CTC patterns in frozen-thawed spermatozoa. The rates of AR pattern were higher in miniature-pig than in Duroc and Yorkshire. However, no difference was found in F, B and AR patterns. The results of present study suggest that further research is necessary to develop of semen extender and freezing methods to improve sperm quality in miniature-pig.