Studies on deep-freezing preservation of chicken semen

鶏精液の凍結保存に関する研究

Watanabe Moriyuki

広島大学水畜産学部紀要

Journal of the Faculty of Fisheries and Animal Husbandry, Hiroshima University

　鶏精液の凍結保存に関する基礎的研究として凍結用各種希釈液の調整を行ない，融解後の精子活力に及ぼすグリセリン濃度，グリセリン平衡温度および平衡時間，各種凍結法および融解法の影響について検討し，更に引きつづき授精試験を行なった結果は次のごとくである.
1. 凍結用希釈液としてはA 液が精子の活力の維持および生存精子割合に最も効果的であった.
2. 鶏精液の凍結保存においては希釈倍率は低い方が良好であった.
3. 鶏精液の凍結方法については37℃で精液を希釈し， 5℃まで毎分1℃ずつ下げ， 5℃でグリセリンの添加平衡を行ない，更にグリセリン平衡後0℃ まで毎分1℃ずつ下げ， 0℃ からー79℃に急速凍結した第4の方法が，また融解においてはー79℃から5℃に5分間静置して融解しその後
20℃に保持するのの方法が精子の活力維持および生存精子割合に最も効果的であった.
4. 上記の凍結ならびに融解法でグリセリン濃度7％， グリセリン平衡温度5℃で60分間平衡したものが凍結融解後の精子の活力の維持および生存精子割合に最も効果的であった.
5. 鶏精子の融解後の活力と凍結期間との聞には何等著明な差異は認められなかった.
6. 鶏精液の凍結保存期間と受精率との聞には著明な差異は認められなかった.

The effect of various diluents, dilution rates, freezing and thawing methods, glycerol concentrations, glycerol equilibration temperatures, holding temperatures after thawing, equilibration times and freezing preservation periods on the viability of chicken spermatozoa were examined and the fertility test was carried out successively. The results were summarized as follows.

1. Diluent A was the most effective in maintaining motility and percentage of motile sperm and Diluent B was the most effective after Diluent A. The effect of Diluent C, D, Locke-Ringer solution and Yamane's solution were clearly inferior to that of Diluent A and B.
2. As for the dilution rates on deep freezing of the chicken semen the buffer diluted for four times was superior to the buffer diluted for eight times and it seems to be necessary for freezing preservation of chicken spermatozoa not to rise the dilution rate.
3. In the case of freezing the chicken spermatozoa, Method 4 was the most effective in maintaining the motility and percentage of motile sperm of the three and Method d) was the most effective of the four in the case of thawing the chicken spermatozoa after freezing.
4. The glycerol concentration of 7 percent was the most effective to protect the survival of chicken spermatozoa thawed out after freezing in the present experiment.
5. The semen samples equilibrated at 5°C was the most superior in maintaining the motility and percentage of motile sperm as compared with that of 10°C and 20°C.
6. The holding temperature of 20°C after thawing was the most effective in maintaining the viability of chicken spermatozoa and 30°C and 37°C ranked to it in order.
7. The semen samples equilibrated at 5°C for 60 minutes gave higher motility and percentage of motile sperm than those of 30, 90 and 180 minutes.
8. There were no remarkable differences between the resumptions of motility of chicken spermatozoa and storage periods when the semen samples stored for 1, 7, 14, 30 and 90 days.
9. The striking differences among fertility when the semen samples stord for 30, 90 and 100 days respectively at -79°C were not observed.

Animal husbandry [ 640 ]

eng

広島大学水畜産学部

[ISSN] 0440-8756

[NCID] AN00213563