Systematic research was madeon factors,such as embryonic quality time present in vitro,developmentstages,corpora lutea and breeds of recipients,which affected pairs of demi-embryos transfer pregnancy rates and demi-embryo calving rates.

• 对影响成对半胚移植妊娠率和半胚产犊率的因素如胚胎质量、胚胎在体外停留时间、胚胎发育阶段、黄体状况、受体牛品种等进行了较系统的研究。