- 期刊
精液品質及卵丘細胞之去除對體外培養牛胚發育之影響
Effect of semen quality and cumulus cell removal on the development potential of in vitro produced bovine embryo
摘要
本研究旨在探討牛胚體外生產系統中，冷凍精液品質及卵丘細胞去除與否對牛胚發育率之影響。試驗分為二部份，試驗一利用精子分析儀（HTM-IVOS型，Hamilton-Thorn, USA）檢測公牛冷凍精液解凍後之品質。主要分析項目包括精子濃度、精子存活率及前進精子率。同時，探討其對體外受精後之牛胚受精率與發育率之影響。試驗二探討牛成熟卵母細胞外之卵丘細胞部份或完全去除再進行體外受精，對其受精率與胚後續發育率的影響。試驗一之結果顯示A與B二頭進口公牛之冷凍精液性狀，精液濃度分別為33.5 與37.1×10^6/ml、精子存活率為40.3%與44.0%、前進精子率為 10.6%與32.0% （P＜0.05）、畸型率為16.3% 與7.6%（P＜0.05）。分析結果顯示B公牛冷凍精液解凍後之品質優於A公牛者。利用A與B公牛冷凍精液解凍後進行體外受精，受精卵之分裂率分別為9.7 %與46.3%，發育至囊胚之百分率分別為0.4%與5.1%，B公牛精液受精率與胚後續發育率顯著優於A公牛精液者（P＜0.05）。試驗二之第一與第二組使用玻璃針進行機械式吸放去除部份或全部卵丘細胞，第三與第四組先使用玻尿酸酶（hyaluronidase）處理後，再配合玻璃針吸放以去除部份或全部卵丘細胞。結果顯示，第一、第二、第三、第四組之分裂率與發育至囊胚之百分率分別為46.7%與10.7%、35.5%與4.3%、39.9%與10.1%、30.7%與3.3%，以玻璃針機械式吸放或配合玻尿酸酶部份去除卵丘細胞組，其分裂率與發育至囊胚百分率均優於完全去除卵丘細胞者。由試驗一與試驗二之結果，得知公牛精液性狀優者，進行體外受精可獲得較佳的分裂率及胚發育率。而進行體外受精前，完全去除包覆在牛卵母細胞外的卵丘細胞，將對受精後之分裂率及胚後續發育率造成不利的影響。
並列摘要
The purpose of this study was to investigate the effect of frozen semen quality and cumulus cells removal on the development potential of the resultant bovine embryos. Trial 1 used the sperm analyzer (HTM IVOS) to determine the frozen-thawed semen quality, including the concentration, motility, progressive movement, and abnormal percentage of sperm, of two bulls imported from USA. The results showed that the concentration, motility, progressive and abnormal percentage of sperm in the frozen-thawed semen from the A and B bulls were 33.5 vs. 37.1×10^6/ml, 40.3 vs. 44.0%, 10.6 vs. 32.0%, 16.3 vs. 7.6%, respectively. The fertilization rate and blastocyst rate of the resultant embryos were 9.7 vs. 46.3% (P＜0.05) and 0.4 vs. 5.1% (P＜0.05), respectively. Trial 2 was conducted to examine the methods used to remove the cumulus cells prior to in vitro fertilization (IVF). In vitro maturated cumulus-oocyte complexes(COCs) were randomly divided into four groups. In group 1 and 2, cumulus cells of the COCs were partially or totally removed with glass micropipette; in group 3 and 4, they were treated with hyaluronidase prior to remove the cumulus cells partially or totally with glass micropipette. The cleavage rate and blastocyst rate of the embryos in group 1, 2, 3 and 4 were 46.7 vs. 10.7%、35.5 vs. 4.3%、39.9 vs. 10.1%、30.7 vs. 3.3%, respectively. In conclusion, the good bull semen quality for IVF and partial removal of cumulus cells of COCs before IVF will benefit the production of bovine embryos in vitro.