The Study On Embryo Transferred For Twinning Of Cattle

The purpose of this study was to apply embryos transfer fortwinning of the cattle to analyse the ways which would improve the rate of twinning and the influence factor, and to establish the technique system completely. The study was divided into two experiments.The frist one is, The Study on Embryo Transplant for Twinning of cattle:20 donors and 70 recipients were divided into A, B, C, D, E, F groups; There were 15 donors in A and B groups .we applied AI+ET for A group and transferred two embryos for B group after nature oestrus. There were 10 donors and 20 recipients in C group and D group for estrus synchronization,The recipients of C group were managed with AI+ET and transferred one fresh embryo and transferred two fresh embryos to the recipients of D group. There were 10 recipients in E and F groups. and the recipients E group were transferred cryopreserved embryo which was gotten from themselves after AI.The recipients F group were transferred two cryopreserved embryos which were gotten from themselves.The results of the experiment indicated that: Applied the way of AI+ET ,The rate of twins(62.5%) of E group transferred cryopreserved embryos which were gotten from themselves was higher than A group and C group (58.33%,50.00%),there was significant difference (P<0.05) between C group and E group and the rate twins (44.44%) of D group transferred with two fresh embryos was higher than B group and F groups which was transferred with two frozen embryos,but there is no significant difference (P>0.05)between groups. The experiment showed that there was no significant difference (P>0.05) between A group and E group ,when the recipients were managed to AI and transfer with one embryo after nature oestrus, but the rate twins of E...