THE THREE PILLARS OF IVF SUCCESS: DONOR MANAGEMENT, VYTELLE’S IVF PROCESS AND RECIPIENT MANAGEMENT
PILLAR THREE: RECIPIENT MANAGEMENT
As a result of new research and better techniques, in vitro fertilization (IVF) is more affordable and accessible for beef and dairy producers. As more producers adopt this technology, Vytelle’s goal remains helping you move your herd forward quickly by multiplying offspring from your elite performing animals, shortening generation intervals, and improving reproductive efficiency. Thus, it is critically important to select the best recipients to carry these offspring and set them up for a successful pregnancy and stressfree calving.
3 PILLARS OF SUCCESS
The first step in managing recipients is selecting the right females to receive embryos. There are multiple areas to manage for successful pregnancy results. Tips for success include:
• Select recipients that are at least 60 days postpartum
• Recipients should exhibit regular estrous cycles prior to synchronization
• Give pre-breeding vaccinations 30 to 45 days prior to embryo transfer (ET)
• Avoid large changes in nutrition 30 days prior to and 45 days post ET
• Minimize transportation before and after ET, to decrease stress
MANAGE NUTRITION FOR RECIPIENTS
Recipient nutrition and health management should be designed in the same way as for pregnant donors. The body condition of the recipient female should be assessed at calving to gauge how she will maintain her condition during lactation. If recipient cows are thin, this could be an indication of negative energy balance which will likely have an adverse impact on embryo pregnancy rate. Ideal recipients should be in moderate body condition prior to receiving an embryo.
Work with a nutritionist to develop pre-breeding, gestation and postpartum rations that will support the maintenance and lactation requirements of recipients. Starting at least 30 days prior to ET, recipient cows should be on a positive plane of nutrition, including complete mineral and trace mineral supplementation. If nutrients, vitamins or minerals are limited, you may see reproductive problems, such as increased interval to first estrus and irregular estrous cycles. By setting cows up on an increasing plane of nutrition prior to ET, response to synchronization will improve. Continue proper nutrition through uterine implantation—40 days post transfer—to aid pregnancy success.
Recipient health management is an important part of a successful IVF program. Before ET, recipients should be 45 to 60 days postpartum to allow complete uterine involution and resumption of normal estrous cycles. Pre-breeding vaccines are regularly given to replacement heifers and cows before breeding season to manage reproductive diseases and their negative effect on pregnancy rates. As the vaccine takes effect in the cow, however, reproductive function is suppressed for a period of time. Therefore, best management practice is administration of vaccines at least 30 to 45 days before ET, ultimately yielding better results. Work with your herd veterinarian to select a vaccine that will cover the reproductive diseases in your area.
SYNCHRONIZATION OF RECIPIENTS
Estrus synchronization is commonly used to set up recipient cows for ET. For recipients to receive an IVF embryo, cows should be in heat 7 to 8 days prior to the day of ET. Cows can be set up for ET using synchronization protocols following the advice of your veterinarian. These protocols take 10 to 17 days to implement; therefore, recipient programs need to be scheduled in advance to maximize ET on one date. Best results are seen using heat detection in conjunction with the synchronization protocol. All recipients must be palpated or ultrasound scanned for a corpus luteum (CL) before ET. The ET technician approves or passes on recipients based on CL quality. On average, 5 – 10 percent of recipients are passed on during implantation. The embryo should be transferred in the uterine horn on the same side as the CL. Producers should minimize recipient handling, calf separation and excess transportation before, during and after implantation, to minimize stress.
MATCH EMBRYO TO RECIPIENT
Matching embryo genetics with suitable recipients drives a successful calving season. Expected progeny differences (EPDs)/estimated breeding values (EBVs) are a great tool to predict offspring traits from specific matings and potential calving performance. This is especially important if young females are used as recipients. Place calving ease embryos in younger females and utilize cows to carry larger or less proven genetics. The ideal beef recipients to utilize in an ET program are those 3 to 6 years of age with calving experience and higher quality colostrum than younger females. Recipient cows carry high quality genetics, so selecting the best females to raise these embryo calves will drive good results. The ideal dairy recipient is a first lactating cow or heifer.
Pregnancy detection can take place from 45 to 90 days post implantation. Pregnancy checks should be scheduled prior to 100 days of gestation. After this point, veterinarians have more difficultly accurately predicting fetal age due to the size and lack of safe access to the fetus. Once pregnancy is confirmed, create calving lists to plan calving dates based on an average 280-day gestation length. Pay close attention to recipient due dates and lactation development. Have a plan to contact a veterinarian if recipients are not showing signs of parturition, which can cause them to go over the due date.
Embryo transfer is an excellent way to speed up generation intervals and quickly increase genetic uniformity in a herd. With the right recipient management, IVF can become a valuable tool for accelerating the genetic progress of your herd.