幼龄羊的周龄及卵母细胞体外培养体系对JIVET技术的影响

Effect of lamb age and in vitro culture system of oocytes on JIVET technology

为了探讨周龄及卵母细胞体外培养体系对幼龄羊胚胎体外生产技术（JIVET）的影响,试验对10只5-10周龄杜寒杂种羔羊进行激素诱导,获取卵母细胞,分别在基础成熟液和含200μmol/L半胱氨酸的成熟液里成熟,再分别在含2%发情羊血清（ESS）的Ⅰ受精液和含3 mg/m L牛血清白蛋白（BSA）的Ⅱ受精液里受精,测定不同周龄羔羊的采卵数量、卵母细胞成熟率和卵裂率。结果表明：5,7,8,10周龄羔羊获得卵母细胞数分别为（111.00±16.97）枚/只、（139.50±28.99）枚/只、（108.50±17.68）枚/只、（42.00±11.31）枚/只,5,7,8周龄羔羊显著高于10周龄羔羊（P〈0.05）;而5，7，8周龄羔羊之间差异不显著（P〉0．05）；试验成熟液获得的卵母细胞成熟率比基础成熟液高3.64百分点;Ⅰ受精液获得的卵母细胞卵裂率极显著高于Ⅱ受精液（P〈0.01）。说明选择5-8周龄羔羊、卵母细胞体外成熟液添加一定量半胱氨酸和体外受精液含一定量ESS可以改善JIVET体系。

The aim of the present study was to investigate the effects of week-old and in vitro culture system of oocytes on in vitro production technology of juvenile sheep embryos（ JIVET）. 10 Dorper-Small tailed hybrid lambs aged 5-10 weeks were induced by hormone to obtain oocytes. The oocytes were matured in the basal maturation solution and the experimental maturation solution containing 200 μmol/L cysteine,respectively. Then the oocytes were fertilized in fertilization medium Ⅰ containing 2% estrus sheep serum（ ESS） and fertilization medium Ⅱ containing 3 mg/m L bull serum albumin（ BSA）. Finally,the number of eggs,oocyte maturation rate and cleavage rate of the lambs at different week-old were determined. The results showed that the number of oocytes obtained from the Dorper-Small tailed hybrid lambs at 5,7,8 and10-week-old were（ 111. 00±16. 97） per lamb,（ 139. 50 ± 28. 99） per lamb,（ 108. 50 ± 17. 68） per lamb and（ 42. 00 ± 11. 31） per lamb,respectively. The number of oocytes obtained oocytes from 5,7 and 8-week-old lambs was significantly higher than that from 10-week-old lambs（ P 〈0. 05）,but there was no significant difference among 5,7 and 8-week-old lambs（ P 〉0. 05）. The maturation rate of oocytes obtained from the test maturation solution was 3. 64 percentage point higher than that from the basic mature solution. The cleavage rate of oocytes from fertilization medium Ⅰ was significantly higher than that from fertilization medium Ⅱ（ P 〈0. 01）. The results indicated that selection of lambs aged 5-8 weeks,oocytes in vitro maturation solution containing a certain amount of cysteine and fertilization medium containing a certain amount of ESS could improve the JIVET system.