Refining Productivity of Bovine IVF Embryo Transfer with Recipient Selection

Abstract

Reproductive efficiency is a critical component of a successful cattle operation. Embryo transfer (ET) is a reproductive technology that cattlemen around the world use, to capitalize on elite females by using common females as a recipient. This reproductive technology has become increasingly common in both the dairy and seedstock sectors. Costs associated with ET deters other producers from utilizing ET technology. By improving ET pregnancy rates, costs decline. A lowered cost and enhanced ET pregnancy rate will appeal to more producers resulting in broader application. It is noteworthy that a small surge in ET pregnancy rate yields thousands of additional dollars for cattle producers. This study addressed factors that potentially contribute to reduced pregnancy rates in recipient cattle. There were five factors assessed in this study: 1) days following recipient estrus (DSE), 2) embryo quality grade, 3) embryo stage, 4) embryo state, and 5) matching embryo stage to recipient estrus. Data from 435 transfers was included in this study. Two factors were identified significantly (P < .01) decreasing pregnancy rates in recipients: days following recipient estrus and embryo state. The state of the embryo exhibits a sizable (40.6% and 18.8%) difference in pregnancy rates. By addressing how many days followed a recipient estrus and the embryo state before transfer can potentially boost pregnancy rates.