Advanced reproductive technologies are exciting and effective, making it easy to jump right in when there are elite genetics that you want to replicate quickly. However, it is important to pause and understand how to create success from start to finish.

There are important decisions a producer makes every day that influence reproductive success long before a technician touches the donor or before a recipient is synchronized. Regardless of whether you are conventionally flushing or leveraging in vitro fertilization (IVF), proper management of the donors and recipients is a major key to successful embryo production and performance.

Establish a nutrition program

Nutrition is the foundation for a successful embryo program, both for the donors and the recipients. A suitable nutrition program should be established and maintained 60 days before an embryo collection or transfer. Providing animals with a positive plane of nutrition directly influences and supports their reproductive performance. Working with a nutritionist to formulate balanced rations to meet requirements of crude protein, energy, minerals and vitamins is key. Requirements will change based on the donor’s age, stage of production and environmental conditions.

Always provide donors and recipients access to a complete mineral program with organic and inorganic sources. Additional supplements including EPA and DHA rumen-protected fatty acids can be offered to donors, as well as magnesium and zinc, which are essential for reproduction.

Animals that are over- or underweight can have altered reproductive hormone levels, increased postpartum interval, and irregular follicular growth and ovulation. Any negative influences (nutritional or environmental) can impact reproduction 60 days later, so it is important to recognize potential nutritional problems early and act on them as quickly as possible to support embryo development and positive pregnancy rates.

Vaccination protocols

Work with your herd veterinarian to maintain annual vaccination protocols. As donors and recipients reside in different locations and environments, there is not a one-size-fits-all protocol for health management.

Pre-breeding vaccines are important for replacement heifers and cows to manage reproductive diseases. For best results, vaccinations should be administered at least 45 days before a conventional flush, IVF collection or embryo transfer. If vaccines need to be administered within 45 days, discuss vaccine history with a reproductive specialist to manage your embryo plans accordingly.

Reproductive management

When enrolling a donor in an IVF program, knowing her pregnancy status is important to schedule collections. The beauty of IVF is allowing a donor to stay in production while still making embryos. Donors can be aspirated up to 100 to 120 days pregnant before she is too far along to safely reach her ovaries. Once she calves, she can be aspirated as soon as 15 days postpartum.

For a conventional flush, a donor should be at least 45 days postpartum before starting a set-up protocol and must remain open for future flushes. If you plan to do consecutive conventional flushes, donors should have at least 30 days in between collections to ensure she has enough time for her ovaries to rest following superstimulation with follicle-stimulating hormone (FSH).

Some producers that use conventional flushing and IVF concurrently will set an IVF collection two to three weeks prior to a conventional flush, using the IVF collection to prime the donor by initiating new follicular growth. To maximize success with this method, be sure to diligently schedule the logistics of the two reproductive technologies.

Recipient management

Recipient management is essential to embryo performance, which is the key to unlocking your return on investment (ROI). As we have touched on above, nutrition and vaccination protocols are foundational and should be incorporated into your recipient herd 45 to 60 days prior to synchronization. Recipients should be at least 45 to 60 days post-calving at the start of a synchronization protocol. In addition to basic management requirements, recipient selection is also a critical success factor. An ideal dairy recipient would look something like this:

• First lactation or first service on second- or third-lactation cows (young)
• Showed a natural heat 30 to 45 days in milk (DIM) (quick return to cyclicity post-calving)
• Less than 120 pounds milk production (not putting all energy into milk production)
• Bred on first service last year
• 80 to 100 DIM at embryo transfer
• No history of mastitis, metritis, lameness or other disease

It is extremely important to maintain high standards around recipient criteria to ensure good, consistent pregnancy rates. Creating embryos is an investment; continuing to be diligent throughout recipient management and selection is vital for embryo performance and ultimately reducing the cost per live calf.

Although the ideal dairy recipient can be hard to always have access to, it is important to understand why the selection criteria exists. Selecting recipients that are fertile, healthy and alleviated from stressful production supports a quality synchronization, enabling pregnancy rate and gestational success.

It is not uncommon for a recipient carrying an IVF or conventional flush embryo to go past their due date. It is important to be aware of and manage it accordingly. In the last 60 days of gestation, a calf gains about 2 pounds per day, so allowing a recipient to go past their due date can result in heavier birthweights.

Now let’s be clear: There is a difference between large calves and large offspring syndrome (LOS), and these two terms are often used interchangeably. Large offspring syndrome is identified by excessive birthweight, large tongue, umbilical hernia, hypoglycemia and enlarged abdominal organs. A large calf is simply a calf that is larger than the producer expected but does not exhibit any other signs of defects.

A longer-than-normal gestational period as well as genetics play a major role in the size of a calf at birth. As an industry, due dates are often overlooked with no protocol put in place if a recipient goes overdue. Being proactive and having a plan for this scenario is in your best interest to ensure live, healthy calves are born. Work with your herd veterinarian for an induction protocol that works best for your region and program.

Maximize your ROI

Understanding the foundation of success in embryo programs is the real key to unlocking genetic progress. Conventional flushing and IVF are heavily used and widely adopted technologies because they work and are efficient. However, their success is supported by reproductive specialists who have spent years formulating and modifying management protocols to get more consistent, positive results. There is no doubt that advanced reproductive technologies can work for your operation; be sure to leverage the existing knowledge around successful embryo transfer programs to maximize your return on investment.