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off implementing the less intensive protocols. Our final level of the female pyramid is embryo transfer (ET), conventional multiple follicle embryo transfer, in vitro fertilization (IVF) and oocyte pickup (OPU). With these technologies, and the use of cryogenic frozen embryos and semen, there is an opportunity to produce offspring from valuable females because these genetics can come from anywhere in the world. This IMPROVING REPRODUCTIVE SUCCESS CONTINUED FROM PAGE 28

allows producers to quickly increase the genetic diversity of their herd without having to purchase high-value animals by using their herd as embryo recipients. Conventional ET commonly achieves slightly higher pregnancy rates than IVF embryos, but OPU/IVF excels for females that are pregnant or with the use of highly valuable semen, such as sexed semen. If we now transition to the bull repro- ductive pyramid of success, it tends to be more difficult to actively intervene with bull success, but there are still a few things that can be done to increase their reproductive performance. At the

bottom of our pyramid is a breeding soundness exam (BSE), which should be performed one to three months prior to the breeding season. A BSE is a physical and microscopic exam per- formed on bulls to evaluate sperm mor- phology, sperm motility, physical health, scrotal circumference, and it is also commonly paired with testing for sexu- ally transmitted diseases. The objective of a BSE is to determine the breeding potential of a bull and examine the bull’s capability of producing offspring. One level higher on the pyramid is to perform an additional BSE at the end of the breeding season. By performing a second BSE, producers can assess the bull’s reproductive ability at the end of the season and make the economic decision to decide if he is worth feeding throughout the non-breeding season. If a bull fails his BSE at the end of a breeding season, a wise economical management decision would be to cull the bull to avoid future mainte- nance expenses as he will not perform adequately next breeding season. How- ever, a BSE is still just an expectation; the bull still must find the females to be productive. The final piece of the bull pyramid is DNA testing. In a multi-sire breed- ing program, it is important to evalu- ate which bulls are being the most productive in breeding for the purpose of eliminating bulls that underperform. Paternity testing is a solution to quan- tify a bull’s success in the herd. Sire verification can be accomplished by retrieving tail hairs from the bull and ear notches from calves. The results will tell producers which of their bulls is not contributing to the reproductive suc- cess of their herd and should be culled. Not only does progeny testing allow producers to remove inefficient sires, but it also improves expected progeny differences accuracy. There are many different pathways to achieve reproductive success. First, you must begin with a desired goal in mind. A commercial cow-calf producer has far different goals than a seedstock producer. However, both still rely on being able to produce a marketable animal year after year. No matter what your goal is, developing an efficient reproductive program will yield positive results as research shows reproductive performance is five times more valu- able than calf growth.

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