The most important thing necessary for your involvement in embryo transfer is selection of your donor female. In my opinion, the best donor from a productive standpoint is a 3-8 year old cow in production that has calved 60-90 days. Of course for the producer, it is best to identify cows that excel in some aspect for your situation whether that be phenotype, exceptional epd’s, show career, etc. You need to propagate a potentially marketable product. That is the ideal situation.

Many of the animals chosen to enroll in an embryo transfer program are not ideal. Expect results to be potentially less rewarding as the “strikes” against the donor female increase. By strikes, I mean age (virgin heifers and old cows), injury (stifle injuries most common), reproductive problems (non-breeders, calving injuries, adhesions both ovarian and uterine). Does that mean they won’t work? Not at all, but expectations should be less for these particular animals. 

It's important to realize that successful embryo transfer programs require intensive management and attention to detail. The results you achieve are highly variable and the level of success is based on your ability to manage all aspects of the operation. I have broken the management into several key areas with suggestions in each area.

1.  NUTRITION

Nutrition is without a doubt one of the most important areas of donor and recipient management. The sources for complete nutritional guides are numerous and should be utilized as necessary. My comments will be very simple and straight forward. 

First of all, I believe the nutritional management of your cattle needs to be a year long process. Attention should be placed on meeting their demands for the entire season including gestation and lactation. The most critical and demanding time however includes the month before calving through the first three to four months after calving. This is the most stressful and nutritionally demanding time to allow that cow to produce a healthy calf via colostrum production, begin lactation to raise that calf, AND become pregnant. Reproduction is not an essential process in survivability of that cow and consequently suffers first in lieu of inadequate nutrition. Maintenance and milk production will partition available energy supplies with reproduction suffering at their expense. Therefore, it is critical to meet their requirements.

It is imperative that your cattle are on an increasing plane of nutrition in preparation for flushing and transfer. This “flushing” effect usually requires supplementation which usually entails grain mixes for most of our clients. Utilize body condition scoring methods if you are not comfortable with purely visual appraisal. Do whatever it takes to be sure these cows are in condition to succeed.

Be consistent in all your management practices but particularly nutrition. Cows are creatures of habit and they prefer consistency. Preferably make no management changes on these cows through flushing and transfer through pregnancy diagnosis after 30 days. In regards to movement of recipient cattle, it is recommended to make any movement of these cattle in the first two days after transfer. Nothing stressful should occur during the 12-15 day window (counting transfer day as day 7) when maternal recognition of pregnancy should occur.

Don’t go to either extreme of body condition. Overconditioning, especially of the donors that will be carried open for an extended period of time is also detrimental to the overall success of ET. Fat cattle also create an additional difficulty in the flushing and transfer procedures. It becomes an art to keep those donors in working condition especially after the calf is weaned.

Utilize any external sources necessary i.e. veterinarian, extension, nutritionists to be sure your nutrition program is covered. 

2.  HERD HEALTH

Total herd health management is also critical in management practices. Many advances have been made in veterinary medicine in recent years. The tendency to look for the next great antibiotic or antibiotic combination to treat the sick cattle has yielded to the preventative approach. We have decided that prevention is much cheaper than treatment and the lingering effects of illness or disease.

This area encompasses vaccination programs as well as deworming protocols. There will be another area of information which will outline our current recommendations for vaccination protocols. Regardless of the protocol you use, leave no holes. Be sure your cattle are protected for the major disease pathogens that you might be exposed to. The purebred cattle business involves much movement in and out of your herds which greatly increase your exposure to new diseases or variant strains naive to your population. Even with stringent vaccination programs in place, this increases your risk of disaster.

Develop an isolation area on your farm. Ideally this would be a location totally removed from the existing cowherd. If that is not possible, at least locate them in a separate pen or pasture for 2-3 weeks before comingling them with your herd. Perform necessary testing and vaccinations at this time.

Devise your vaccination program to allow you to NEVER vaccinate the donors and recipients within 30 days of breeding or transfer.

3.  STRESS

Stress is an important factor in ALL aspects of your program. Most people are aware of the radical stress associated with cattle prods, dogs, noise, etc. that can occur and try to minimize them at breeding and transfer. For those of you that are not, please become aware. I don’t think most people are aware of the negative impact that even subtle stresses that occur in handling has on other areas of cattle management such as vaccine effectiveness, weight gain, and overall health especially in the calves on these recipient cows.

I challenge most of the cattle owners (including myself) to reevaluate the conventional methods used in processing cattle. There was a presentation at the 2009 AABP meeting for veterinarians that outlined the success of changing the methods of handling cattle. The results in calf health and weight gains were remarkable. For most people, we think we are doing it the right way now, but I challenge you to rethink your technique.

The area I think it is most remarkable and the situation where I see it most abused is in loading the alleys and the sweep tubs. The cattle are approached totally different from our normal approach to drive them from behind and put as many as we can in the alleys and keep them full. I recommend you look at the videos on www.ranchtv.org. This site prepared by Texas A&M outlines many areas of management but please view the videos on low stress handling. 

Superovulation is the process utilized to force your donor to produce multiple ova to become fertilized for embryo collection. It involves the administration of an FSH (follicle stimulating hormone) product over a period of days with multiple injections. Some of the products used currently are Folltropin and Pluset.

For many of you this will be remedial, but for the new owners, I will make some general

guidelines to follow.

• The products will need to be reconstituted prior to administration. Alwaysuse a sterile needle and syringe to add the diluent to the powder
• Always refrigerate the bottle after mixing
• Use a sterile 3cc 20gauge 1.5 inch needle to administer the FSH. Do NOT
• Use the same needles and syringes on multiple donors. This creates unnecessary risk of transmitting diseases particularly Bovine Leukosis Virus throughout your donor population.
• Give injections deep IM following BQA recommendations (in the neck).
• Do NOT give them on the top of the hip particularly in fat animals. This is an IM product and can be injected in fat on some animals.
• Follow your schedules closely. Donor injections should be given 8-12 hours apart. Follow the amounts as scheduled closely. As we gain experience with each donors, the dosages they receive will vary. It is imperative that you follow your schedules.
• Freeze any unused FSH in the bottle. You can use this in the future if you need a small amount to finish another donor. 

Now that you have followed your schedules and programmed your donors and recipients, it is important that you are prepared for flush day. As mentioned earlier, manage your cows in the same manner after your heats and breeding as you did prior to procedures. Keep your cattle on their gaining plane of nutrition and continue to utilize all management practices to minimize stress.

On actual day of collection, please have your donors up prior to arrival in a comfortable pen. It is very important that you have all of the donor names and registration numbers as well as the sire names and registration numbers. As an AETA certified business, it is our responsibility to be sure that information is provided on all our paperwork but most importantly it must be used when processing frozen embryos.

Depending on how many donors are being flushed, the recipient cows may need to be penned also. At least you should have them in a smaller area close to the chute. If you are using “heats” on your recips, have that information also written in a concise legible format.

After the donors are flushed, they will be given a shot of prostaglandin to minimize the risk of a retained embryo(s) and a resulting pregnancy in your donors. Depending on your future plans for this donor, it is advisable to give a second injection of prostaglandin 3-5 days later. After transfers are made into the recipients, they should be handled very quietly. If moving them to a new farm or location, it is recommended to move them either transfer day or possibly the next two days. Do not handle them from five days after transfer through twenty-five days to provide them with their best chance to recognize pregnancy. 

Although not as critical as the donor selection in terms of your operation, it does not lag far behind the donor in terms of the success of your ET program. It does not make sense to choose potential recipients from the bottom of the cow/calf sector. Why place the most valuable progeny you may produce to the least proven or productive cows? That point being made, the ideal recipient does not differ from the ideal donor. I would prefer a 3-8 year old recipient that has calved annually and that has calved 60-90 days prior to implant.

What about heifers? In the earlier years of embryo transfer, I would have said this was ideal from the embryologist standpoint to maximize pregnancy rates but maybe less ideal in terms of a heifer’s ability to achieve acceptable weaning weights on the calves for the producer. Over time, I think this situation has evolved for various reasons to the point now that I would place heifers near the bottom of the selection chain. It seems these heifers are less predictable in their pregnancy rates and seem to incur more failures than mature cows. Some of the fertility issues possibly being involved in those situations could include cyclicity of those animals, growth implants, nutrition (over conditioned and under conditioned) as well as factors we have yet to identify. If, however, that is the animals you have to work with, they certainly can be useful with the understanding of the stated risk.

First calf heifers are also commonly used as recipients. Typically, these are the most difficult animals from a producer standpoint to get pregnant in natural service herds. It stands to reason that they would be the most difficult to get pregnant in embryo transfer. I do believe that is strictly a nutritional issue and very successful pregnancy rates can be achieved in the level of nutrition is increased in this set of cows.

Lastly in the recipient pool are the open cows of unknown origin with the most common source being a sale barn. These are obviously last on my list. My comment to most producers is typically “why do you think they are in a sale barn?” One exception to that comment occurs with a group of mismanaged first calf heifers that never had a reasonable opportunity to become pregnant on the farm. Under proper management and time, they have worked very well. 

There are currently many methods of synchronization available today. All of them have 

one purpose and that is to synchronize the recipients’ heat to the same time as the donor. 

Many people have the misconception in the beginning that the recip cows should be in 

heat the day of transfer. Remember, we are transferring 7 day old embryos. They must be 

placed in the uterus of the recipient cow in the same hormonal environment from which 

they are removed. The recip must be in heat within 24 hours before or after the donor. 

Although there are many options available, I am only outlining the two systems we 

currently use for almost all of our transfers. 

1.  Select Synch + CIDR 

• Day 0 Insert CIDR (slow release progesterone devise) and give 2cc GnRH                  
• Cystorelin, Factrel, Fertagyl, InSych) 
• Day 7 Remove CIDR and give injection of Prostaglandin (Lutalyse, Estrumate, 
• Prostamate) 
• Heat detect for all standing heats 24 hours before and after donor heat 
• Keep an accurate record of the times of standing heat for the recips. 

2.  Controlled Ovulation Program (Co Synch + CIDR) 

• Schedule is exactly as #1 with the only variation being a second injection of GnRH 
• 48 hours after the CIDR/Prostaglandin. 
• This protocol alleviates the need for heat detection.
• This schedule works very well in all groups but we tend to use it more in the large recipient pools. Adherence to the protocol is a must.
• GnRH injections should be given with a 3cc syringe with a 19-21 gauge 1.5 inch needle IM.
• You should see approximately 40% of the cows in heat when you get them back up for the second GnRH injection at 48 hours. After that injection, you will see very little heat activity. Do not be alarmed. This protocol will synchronize ovulation. 
• All recips are then brought through the chute for palpation for a CL.
• On average, 80% of the cattle programmed will receive an embryo.