초기 임신우의 공란우 활용이 초음파 유도 난자 채취 및 수정란 생산에 미치는 영향

Abstract

This study was carried out to evaluate the effect of early pregnant cow as donor for Ovum Pick-Up (OPU) derived oocyte aspiration and embryo production in Holstein heifers. Four non-pregnant and 2 pregnant Holstein heifers were used as donor and then carried out total 17 OPU session for 10 weeks (2 times per week). Recovered cumulus-oocytecomplexes (COCs) were classified into 4 grade by oocyte cytoplasm and cumulus cells and matured in vitro in TCM-199 supplemented with 10% FBS, 10 mg/ml FSH and 1 mg/ml estradiol in 5% CO_2 and over 99% humidity for 24 h. After 24 h co-incubation with post-thaw sperm, the presumed zygotes were cultured in CR1aa medium with 4 mg/ml BSA for 3 days and then changed CR1aa medium with 10% of FBS for another 3~4 days. The Mean number of aspirated follicles and collected oocytes in the early stage pregnant and non-pregnant heifers were 13.0 ± 4.3and 10.6 ± 3.9, 5.4 ± 3.4 and 7.7 ± 3.6 per session, respectively. Rate of collected oocyte from aspirated follicles were 59.2% and 50.5%, respectively. The average number of good quality oocytes (Grade Ⅰ and Ⅱ) in the early stage pregnant and non-pregnant heifers was 3.7 ± 2.7 and 4.9 ± 2.6 (Mean ± SD). Cleavage and blastocyst developmental rates in Grade Ⅰ and Ⅱ were 22.2% and 25.5%, and then 1.7 ± 0.9 and 1.4 ± 1.1 blastocyst per session, respectively. In conclusion, OPU technology can be used in early stage pregnant and non-pregnant heifers without any problem and so applied OPU derived embryo production to maximize the ability of genetically valuable females.