性别控制与体外受精技术快速繁育高产奶牛群

使用流式细胞分离仪可以将X精子从Y精子中选离出来,分离精度高达90%或更高。这种性别控制(性控)技术可以用来生产性别预选的家畜以及优化育种的方案。然而,精子分离的速度以及其性控冷冻精液的不同受精力仍然限制着该技术的广泛应用,尤其是在传统的人工授精育种方案中。体外受精技术(Invitro fertilization,IVF)提供了一个可行而有效的手段来提高奶牛性控精子的受精效率。本文介绍了有关利用IVF技术来控制奶牛性控胚胎发育率和提高雌性胚胎质量的新方法,从而提高胚胎生产效率,达到快速繁育高产奶牛群的目的。这些IVF程序包括以优化的方法遴选出用每头公牛X精子进行IVF所需的最佳肝素浓度;减少IVF受精液的体积以确定每枚卵子获得受精所需的最少精子数目;在体外培养液中使用果糖来替代葡萄糖,以及使用能超速降温的玻璃化冷冻技术。

Generating Dairy Cattle in a Large Schedule by Sexed IVF

Flow cytometry can separate X-sperm from Y-sperm with an accuracy at 90% or higher. This sperm sorting technology offers the livestoc, k industry the potential of a double productivity, by producing the desired sex to optimize breeding programs. Sorting speed and fertility variation of sorted sperm, however, remain limiting factors for widespread application, particularly in traditional AI programs. Alternatively, in vitro fertilization is a feasible and efficient means to increase the fertilization efficiency of sex-sorted sperm in cattle. Procedures to increase fertilization rate and improve embryo quality include optimizing heparin concentrations for semen of each bull, reducing fertilization drop size to increase sperm concentration, use of fl＇uctose instead of glucose in culttlre media, and use of vitrification protocols with extremely rapid cooling and warming rates.