December President’s Letter

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Published on: December 21, 2012

As my term expires at the end of December I would like to take this opportunity to thank Jeremy and the FASS staff as well as the AETA board of directors for a great year. Thanks to the leadership of previous boards putting us back in a stable condition after plummeting off our own “fiscal cliff” several years ago we are now able to look at opportunities to enhance member benefits. It is a lot more exciting to attend board meetings now to discuss new ideas and vision statements than to worry about how to pay the bills. So as we move forward I would just like to thank those individuals who handled the GMO crisis for the opportunities we have now. I think the future is bright and I would encourage anyone to get involved on a committee or the board. The new set of officers is the youngest group we have had in a long time, so expect plenty of good things to come.

To give more consistency to the terms of directors and officers, they will officially take office beginning January 1. In the past, terms have been between annual meetings, but with dates changing each year for those from mid August to late October it would have some serve 10 months and some 14 months. This also gives a period between being elected and taking office to transition critical duties such as treasurer.

I would like to thank our Canadian colleagues for hosting an outstanding meeting in Winnipeg. Highlights of that meeting as well as a summary of the board of directors meeting are contained in this newsletter. Our intent is to provide a summary of issues from the board meeting so members can proactively participate on these as they are being developed instead of reacting to them after the board has implemented action. Please take time to read this summary and give us your opinion.

I had the opportunity to take advantage of one of our new programs this fall. Dr. Looney invited me to spend a day working with him at a client’s facility. We were able to spend all day and half the night discussing embryo transfer with a little Razorback and Wildcat football mixed in as well as next year’s meeting in Reno. Aside from the certification credit available, I probably learned as much in that one day as any meeting I have ever attended. I absolutely would encourage everyone to use the excuse of obtaining “Certification Credit” to get to visit another practice, even if you don’t need the credit, and thanks Charles for the hospitality.

Glenn Engelland

Incoming President’s Letter

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Published on: December 21, 2012

As my term is set to begin with the start of the New Year, I would echo Glenn’s sentiments that it is an exciting time to be a member of the Board of Directors.  Our organization rests on sound financial footings and we have been afforded the opportunity to work at supporting our membership in new ways and perhaps foster new ideas.  We have a tremendously talented group of individuals serving on the Board and I sincerely look forward to working with them all over the coming year.

Our vision statement and by-laws clearly identify education as the organization’s first priority and the Board is active on this front in several ways.  A small ruminant training video is scheduled to be filmed this winter and the Board is looking into other ways to support training programs on the bovine side.  As we look at ways to support education and improve member services, I would like to remind our membership of the four student scholarships that are available for the coming year.  The Board of Directors had the opportunity to spend some quality time with last years’ winners in Winnipeg and it was certainly a highlight of the meeting.  The membership committee did an outstanding job in selecting four impressive, well-spoken individuals with a sincere interest in our profession.  Please keep these scholarships in mind as you meet and mentor potential new members of our organization.

For those of you unable to attend the conference in Winnipeg you missed a very good scientific program with outstanding speakers.  With some help from the Canadians, we were fortunate in being able to arrest and incarcerate some of the more prominent members in attendance at the preconference social.  While the jail at the “Hitchin Post” was all in good fun, I would like to sincerely thank those who tolerated their time behind bars for a good cause and were great sports all around.  Contributions from the attendees to “post bail” were entirely directed to the student programs.  Thanks to all.

Please take care and be safe during the upcoming holidays.

Kevin A. Lindell

Board of Director’s Meeting, September 2012

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Published on: December 21, 2012

The AETA Board of Directors works hard at managing the Association.  Now, much of what the Board accomplishes is not seen by the membership:  the meetings are closed and the minutes are not published.  This article is written to give the membership a better understanding of Board function as it presents a brief look at a Board meeting.

The Board meets at least twice a year, once at the annual meeting and once in mid-winter.  These meetings are a systematic review of all the activities of the AETA.  Each committee files a written report and these reports are read and discussed in detail.  Any Board recommendations or action points are returned to the committee chairmen.  The financial status of the association receives its own very thorough review.

These discussions are thorough, detailed, and comprehensive.  They would probably not make for good reading in a newsletter.  There were several additional topics that were discussed that should interest some of the membership.

Money would be a good example.  The AETA has a very solid financial status.  It should be noted that the AETA switched banks in order to accomplish lower service fees on their accounts.  Interest on deposit accounts is very low; decreasing service fees helps to offset the low interest income.  The appropriate level of cash reserve was discussed.  And several ‘returns’ to the membership were also discussed; one return that was enacted is a $50 credit for any individual filing their statistics report early.

Education is another large topic of discussion.  Education encompasses several committees and has its own financial impact.  Over the past few years strong interest has grown in the area of small ruminant embryo transfer and attendance at conference-associated wet labs has been excellent.  Plans are being developed for the production of a web-based training video and  DVD focused specifically on small ruminants.  The mainstay of the association, bovine ET, remains in focus with an ET 101 wet lab and a mentoring program under discussion.  A special break-out session for technicians and another pre-conference symposium with the IETS are under consideration.

The AETA Vision Statement was reviewed.  It was noted that the AETA has accomplished a great deal of programmed growth through the vision process.  The Board plans to reexamine the Vision Statement at its winter meeting.

Finally, there was some discussion as to whether or not IVF calves and/or donors should be uniquely identified.  Donor dams and calves resulting from standard ET procedures have been specifically identified for years.  There are unique feature to the IVF process and offspring that could warrant identification.  This topic is still under consideration.

So, this is all part of a day’s work for your Board of Directors.  Please feel free to contact a Board member or Jeremy at the AETA office if you have a question or concern that you believe the Board should address.

AETA Board of Director Pictures

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Published on: December 21, 2012

2012 Annual Meeting

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Published on: December 21, 2012

The annual meeting of the American and Canadian Embryo Transfer Associations was held this September in Winnipeg, Manitoba, Canada.  The meeting was a great success with 221 attendees, 146 from the AETA and 79 CETA/ACTE.

The AETA sponsored four students at this meeting.  They have each written an essay on their experience at the meeting.  Those essays are presented in this newsletter.

The AETA would like to thank CETA/ACTE for hosting this year’s meeting.  Special thanks to Karen McDermott for her individual effort in coordinating the meeting.  All the events and sessions ran smoothly.  “A good time was had by all.”

Please enjoy the collection of pictures taken at the meeting.

And don’t forget that the Proceedings are available online at the AETA website http://www.aeta.org/mtg_proceedings.asp?yearquery=2012

Pictures from the Thursday Night Social at the Hitchin’ Post

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Published on: December 21, 2012

AETA 2012 Scholarship Winner: Jason Zwilling

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Published on: December 21, 2012

The AETA convention was a great experience for me as a student nearing graduation. I greatly appreciate the support of the organization for the student scholarship. Beyond the monetary support, the membership continued to be inviting to the students during sessions and events. I was surprised by the number of practitioners that voluntarily came to introduce themselves to me. Many of these conversations were quite informative and I was able to gain useful information of the expectations practitioners have of graduating veterinarians. Specifically, the most beneficial educational sessions for me were the practitioner’s forum, animal health discussions, and the industry talks.

The practitioner’s forum was one of the most enjoyable veterinary experiences I have had since starting veterinary school. It was very interesting to listen to the various approaches to solving problems in ET. I was impressed that the group was able to, for the most part, have civilized discussions. This was one of the only experiences I have had where the academic veterinarians and practicing members had an equal contribution and a mutual respect for one another. The forum also showed me how important record keeping can be to solving problems and observing trends. In school we are taught the basics of epidemiology, data analysis, and population statistics.  The forum showed that with a quality data set the ET practitioner can evaluate their own performance, understand trends, and perhaps add some level of predictability to a highly unpredictable business. One of the take home messages for me was that there are many ways to approach a problem and for the most part they can all be considered as correct.

The animal health discussions were largely based on their effects on reproduction. However, they were big picture topics covering diseases that are important to any beef operation. The lecture on BVD brought some interesting questions with the discussion of finding the virus in semen of systemically post-infection bulls. The lecture about nutrition and reproduction was also very informative. The lectures were able to present both the known information and shed light on what is still to be discovered or topics while believed anecdotally but have little scientific evidence to support. As a student with a predominately beef background, I found the topics presented by those in the dairy industry interesting. Specifically, in dairy production the environment, nutrition, and management is more controlled and similar across cows and groups of cows. So from a donor standpoint perhaps individual cow variation is more a factor than environment and management as is seen in the beef side of the industry. Some topics of my interest could be applied to beef or dairy embryo transfer included increasing heifer progeny, sexed semen, and “problem donors”

The discussions of the industry by its leaders were also interesting. From my standpoint as a student, I enjoyed hearing presentations from people I had heard of or read research from in the past. I also enjoyed receiving an understanding of how the Canadian cattle industry works. The presentation from Semex was interesting from a standpoint of how real advancement in a technology had changed the semen freezing process. The highlight of the industry discussions was the presentation on Genomics in my mind. This is rapidly expanding technology in the beef and dairy industries. Our ability to unlock the genome has the potential to greatly change the veterinary approach to problems if we are able to identify those individuals that are more resistant to disease. Genetic selection through EPDs and genomics were topics briefly covered in the veterinary curriculum. The genomics discussion really introduced me to how important a practitioner can be in the process of education and explanation as the field of genomics expands.

In closing, I would like to thank the organization for the scholarship and opportunity to attend this year’s convention. I appreciate the willingness of the members to converse and share experience with the students. I felt welcomed and comfortable with the leaders and membership of the AETA. The experience increased my desire to work in embryo transfer after graduation. I hope to continue my membership in the AETA and take advantage of the educational opportunities through the convention.

Jason Zwilling

 

AETA 2012 Scholarship Winner: Jason Anton

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Published on: December 21, 2012

I had the pleasure of being a scholarship recipient at this year’s American Embryo Transfer Association (AETA) meeting.  This meeting provided me the opportunity to meet professionals involved in embryo transfer (ET), learn about current and developing methodologies in the field of ET, and understand the integral relationship that exists between researchers and practitioners.  This meeting also broadened my perspective of the veterinarian’s role in food animal reproduction.  The various topics covered provided me with a well-rounded perspective of ART in academia and industry.  Also, I was greatly encouraged by the direction AETA is moving in hopes to create more opportunities for students and young practitioners.

One of the most beneficial aspects of attending the meeting was having the opportunity to meet numerous individuals that have dedicated their careers to embryo transfer.  I also appreciated meeting this year’s board members and learning more about their background in the profession. It was through these introductions and the candid conversations that allowed me to establish rapport with future colleagues.  I have always believed in the importance of mentorship, and I was grateful to be surrounded by practitioners that were more than willing to provide me support when needed.  Overall, I genuinely felt that the association as a whole was very welcoming and I look forward to being continually involved with AETA in the years to come.

I thoroughly enjoyed the diverse subjects covered in the talks, and I felt that the subject matter was broad and comprehensive.  I was pleased to see the topic of nutrition covered as it relates to reproductive efficiency and now have a better appreciation of the role that nutrition plays in assisted reproductive success. Since I became interested in embryo transfer, I was always told that there was a slight disconnect between academia and industry.  Specifically, I was informed that little collaboration occurs between our academic institutions and the private sector.  However, at this year’s meeting I found that more collaboration exists than what I was led to believe.  The individuals that represented academic institutions presented information that could be utilized in everyday practice of the ET practitioner.  The practitioner’s forum was one of my favorite aspects of the meeting.  As a budding ET practitioner, I don’t have the experience of trial and error on my side.  With that being said, I was able to listen to practitioners of varied backgrounds candidly discuss what methodologies worked and didn’t work.  This knowledge will better prepare me for success after graduation when I pursue a career in assisted reproductive technologies.

I am very grateful to the organization for increasing their educational budget this past year to facilitate more student opportunities.  It is clear that AETA has a genuine interest in generating veterinary and graduate student awareness of the association. I believe that the current attempts by AETA will only lead to more rapid growth and greater student involvement.  Furthermore, the foundation that is being established by AETA for young practitioners will only lead to greater retention of these members throughout the years.

In closing, I want to again thank the AETA and its members for the opportunity to be a part of this year’s meeting as a scholarship recipient.  I look forward to attending future meetings, and I hope to continually give back to the association in the years to come.

Jason Anton

AETA 2012 Scholarship Winner: Eric Rooker

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Published on: December 21, 2012

Winnipeg, Canada greeted me with 50 mph winds and sold out hotels, but sent me home with a pocket full of business cards, a cell phone full of new peer connections, and a renewed outlook on my future in the bovine industry.  In the days leading up to my first American Embryo Transfer Association Conference I began to worry some that I would have trouble meeting my objective of networking with potential peers and future employers, and being as shy as I am, I would end up being just another face in the crowd.  Needless to say, I should not have worried.  The very first day I was greeted by Jeremy Holzner who was instrumental in directing me to the annual meeting and was also gracious enough to sign me up for ET 101.  While standing outside the doors of my first lecture, I turned to see two mentors and friends in the crowd; Dr. Byron Williams of EmQuest and Dr. John Rathje of Grantsburg, WI who were two veterinarians that I have looked up to since I was a young boy back in my hometown.  These two well respected veterinarians were the first among MANY who greeted me with open arms, advice, and totally unexpected but much appreciated meals.  With my worries aside, and friends in my midst, I walked with confidence into my first seminar; ET 101.

ET 101 proved to be one of the best seminars I have ever had the pleasure to attend.  It also helped me fulfill my second objective of learning how to break into the advanced reproductive services industry.  Doctors Hinshaw and Whitaker proved to be dynamic speakers who took a subject that is always discussed with much technicality and brought it down to the level of a novice.  They offered me great advice on how to integrate myself with a current practitioner through a three step plan, as well as, what tools of the trade to not cut corners on (microscope and freezer) and which tools I could be a bit more frugal with.  They also explained the difference between the current market superovulation drugs and why you would use one drug with and increased FSH:LH ratio over another, in addition to, what drugs to go to if an animal should develop a resistance to their FSH stimulant.  We were able to discuss baseline superovulation and recipient synchronization at a level a beginner could understand without the classic discussion of tweaking the dose of each shot.  We were shown expected baseline benchmarks for pregnancy in an ART system and what you should be striving for grade and stage pregnancy wise.  We touched on the financial aspects, (what we could expect as reasonable fees and costs) and recuperating from disasters such as an accidental spill of a dish.  Learning from some of the leading researchers and practitioners in the industry was just one of many opportunities AETA provided me during the conference.  Other areas of interest that I found to be very informative were topics ranging from how to implement a newly developed five day CIDR program, genomics and its uses, and the effects of nutrition on reproductive performance in our donors and recipients.

The conference also offered me an opportunity to interact with industry representatives at an individual level since the conference was smaller than other industry conferences I had previously attended.  I was able to learn much about emerging technologies ranging from hormonal assays, embryo freezers and new media.  AETA also offered me a chance to join in discussions with practitioners that were talking with industry representatives about pricing and company product selection.  It was enlightening to see the interactions between the two parties, as well as, discussions about the reasons for selecting the company they received different supplies from.  Yet again, the practitioners were teaching me even when I didn’t realize it.

Finally, I would like to thank the many practitioners that took time out of their day to talk with me, who gave me advise on my job hunt, encouraged me to continue my pursuit in this field even though at times it is challenging to get experience when in school, and offered very valuable practice advise.  I would be remiss to forget to thank the practitioners that took me out to dinner. Your camaraderie made the conference even more of a joy to attend; thank you for reaching out to me.  Again, I would like to thank the AETA and all the members for honoring me with this scholarship.  I truly look forward to working with many of you in the future.

Eric Rooker

 

AETA 2012 Scholarship Winner: Joel M. Anderson

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Published on: December 21, 2012

The plains of Winnipeg didn’t bring to mind cattle country, but served as a great site for the 2012 CETA/ACTE and AETA Joint Annual Convention.  Thank you so much to the AETA and the Membership Committee for selecting me as a scholarship recipient.  The meeting was a great intermission from clinics and a unique opportunity to travel to the geographical center of Canada.  I would like to commend all involved on a fun and well executed meeting.

My journey to Winnipeg and my interest in applied reproductive strategies began with a passion to work in the beef cattle industry that stems from our family farm.  Bovine veterinary medicine has changed with the ever-evolving landscape of production agriculture.  I grew up working with our local veterinarian and enjoyed the large animal calls; however, in just the few years it has been since I graduated high school, higher corn prices have led to the removal of fences and cattle around my hometown.  I realized it would take drive and creativity to work in the beef cattle industry. I chose to investigate other areas of beef production, and found my passion for the embryo transfer industry.

I was urged to apply for the scholarship from a number of active members of the AETA.  The mentorship experience I’ve received throughout my college career allowed me to travel the country and gain a greater understanding of the impact embryo transfer has on the cattle industry.  I was drawn to attend the annual meeting to get the chance to meet and learn from more experts of both the AETA and CETA.  I enjoyed visiting with folks from all areas and hearing their perspective on getting more pregnancies for their clients.  The chance to visit and talk about cattle was enough of a draw to Canada, but the program of meetings covered a wide array of timely topics and far exceeded my expectations.

I arrived in Canada just in time to attend the ET 201 Seminar.  Dr. John Hasler and Dr. John P. Verstegen provided interesting discussion on superovulation products that may lead to alternative programs for producers.  Folliculogenesis is the center of the embryo transfer industry and the ability to gain more embryos with less human error will continue to drive research in this area.  Dr. Jon Schmidt detailed the proper handling of IVF embryos in the field.  IVF technology has made its mark in the on-farm transfer business and manipulation of these embryos will be vital to meet client needs.  The seminar concluded with presentations on superovulation schedules and recipient management.  The variation in ways to get embryos from cows will always amaze me, but the most important aspect of any successful program is live calves on the ground.

The program continued with quality speakers who touched on aspects beyond retrieving and transferring embryos.  The topics incorporated a wide-angle view to the success of the future of the cattle industry.  Animal health was discussed by looking at BVD, semen quality, nutrition and postpartum uterine disease.  This reaffirmed the adage of looking at the entire cow, and brought to mind that I shouldn’t focus only on embryos in the dish.  Genomics continues to be a buzz word and will have an impact on the future of animal agriculture and my future relationships with clients.  The Practitioners Forum was the highlight of the sessions.  Discussion filled the meeting room as the presenters provided insight into their areas of interest.  The many “tricks” these practitioners presented sparked my curiosity to always be on the lookout for a new way to complete a task.

The camaraderie and fervor that accompanied the discussions was unique from any other conference I have attended.  The collegiality of the AETA and CETA was overwhelming at the meeting.  The AETA has taken an approach to allow practitioners to visit with one another for continuing education credit.  I believe this will be a valuable tool to moving the industry forward.  The topics presented will impact my provided ideas to draw on once in practice.  The science is vital, but the relationships I made and strengthened during my trip will prove to be an integral part of my future as an embryo transfer veterinarian.  The future of not only the AETA, but also animal agriculture resides in our ability to work together.

Thank you so much to the AETA for your investment in my education.  It was a great trip to Winnipeg and made the trek back to Columbus, Ohio for clinics very difficult.  The scholarship program selected a great group of individuals this year.  I was honored to attend with Jason Anton, Eric Rooker, and Jason Zwilling.  Thanks so much for your support as an organization and I look forward to seeing you in Reno.

Joel M. Anderson

Open Letter to My Colleagus at CETA and AETA

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Published on: December 21, 2012

In September at our Annual Joint Convention in Winnipeg, I was flattered to be asked to host the Banquet evening as Master of Ceremonies.  I enjoyed the experience, and relished the chance to once again  poke a little fun at my American colleagues.  However, herein lies my reason to write this letter to you all.

During the evening, I made light-hearted comments about the War of 1812.  The 200th anniversary of this war between America and the British colonies of Canada has received a lot of attention in the Canadian press.  There is no doubt of the importance that this conflict had in shaping the future of the North American continent, as it played a very important role in establishing Canada as a nation.

Since that time I have read two books by Pierre Burton, a celebrated Canadian author who has written numerous historical accounts of Canadian events.  These books, collated into a single volume entitled “The War of 1812″ to commemorate the 200th anniversary of the War, were vintage Burton.  I thought I would devour the words eagerly, as I was proud that Canada was able to successfully defend itself from America in this conflict.  I expected my patriotic juices to flow freely.  However, Pierre Burton gave a passionate chronicle of the years of conflict which was by no means something to be happy about.

The War of 1812 was a vicious, bloody, and senseless event for people on both sides of the conflict.  There was no feeling of patriotism in my heart after finishing the book, and I was left with the realization that I had made a huge mistake in trying to make humor out of this travesty of history between our two countries.  So today I want to apologize to all of my friends and colleagues who attended the banquet in Winnipeg.  My attempt at humor was very inappropriate.  I should have instead been celebrating the very special relationship that our countries have as neighbors, and that I cherish as colleagues and friends.

Sincerely,

Gary Morgan

Evidence-based ET: For what time span can bovine embryos be maintained between recovery and freezing without compromising viability?

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Published on: December 21, 2012

John F. Hasler

Introduction – After our annual conference in Winnipeg, our AETA Board of Directors asked me if I would be willing to start a column in A Closer Look that deals with practical ET problems and provides published documentation for the subjects and issues in question. I agreed to do this and the following is my first ‘column’. All of us hold personal opinions on numerous technical aspects of our ET profession. In some cases these opinions are based on well-established principles. However, in some cases we all base opinions primarily on ‘clinical impressions’. I believe that such impressions can sometimes be entirely accurate, but I also know, from personal experience, that unless one accumulates an adequate data base, clinical impressions can sometimes turn out to be wrong. Consequently, this column will present information that has some published documentation and is based on more than just my personal opinion or, in fact, undocumented opinions period. Our board members have submitted a number of suggested topics and have given me the freedom to pick among them. I will attempt to adequately document any subject that is covered in this column. Also, please feel free to suggest future subjects that you feel are of interest to most of our membership.

For what time span can bovine embryos be maintained between recovery and freezing without compromising viability?

For a 10 year period from the mid-1980s to the mid-1990s, Em Tran, Inc. shipped many thousands of frozen embryos from Holstein donors in the US to Holland Genetics, The Netherlands. During one phase of this program, we kept very precise track of the time, down to the minute, between flushing and freezing, out to a maximum of 3 hr or 180 min. Of a total of 2,102 embryos frozen in glycerol during this period, the pregnancy rate for embryos frozen between 0-30 min after flushing was 54.1% and did not vary significantly among 30 minute blocks of time out to the 150-180 min group, which had a pregnancy rate of 55.7%.  These embryos were held at ambient lab temperature in Dulbecco’s modified PBS, which we purchased in the powder form and reconstituted in MilliQ water in our lab, adding antibiotics and 10% FCS. The recipients were primarily Holstein cows.

Another data set generated from 3,570 embryos frozen in the Netherlands at Holland Genetics and transferred within the country showed a slightly different outcome (Otter, 1994). The pregnancy rates were 71%, 66% and 57% for embryos held for 0-2, 2-4 or 4-6 hr respectively. These differences were statistically significant.

I recently uncovered a publication on this subject that I had long forgotten about. At the 6th AETA convention in Orlando FL, in 1987, our former AETA president Stan Coley presented some very interesting frozen embryo data from his ET practice in GA. Stan presented data indicating a very high pregnancy rate (75%) for 300 embryos held in in modified PBS + 0.4% BSA and frozen in glycerol within 4 hr post collection. The pregnancy rate was slightly lower for 76 embryos held at ambient temperatures for 4-8 hr before freezing and lower yet (39%) for a small group of 31 embryos held for over 8 hr. Maintaining a total of 91 embryos at 4°C for over 8 hr did not substantially improve the pregnancy rate (46%) compared to the 8 hr group held at ambient temperature.

Pregnancy rates of frozen-thawed embryos are the best index of embryo viability. However, in vitro culture after thawing also can provide meaningful information. In a study conducted at Virginia Polytech (Jousan, 2003), embryos were recovered from donors, maintained in holding medium (OCM; ECHM-500, Immuno-Chemical Products, Ltd.), at either 5 or 22°C for 2, 6 or 12 hr and then frozen in EG. After thawing the embryos were cultured in a commercial IVC medium and examined after 72 hr of culture. There was no difference in the development rates of embryos held for 2 versus 6 hr prior to freezing (86 vs. 79% respectively), but embryos held for 12 hr had a significantly lower survival rate (54%). Holding embryos at 5 versus 22°C prior to freezing did not improve the survival rates for any of the holding periods.

Unfortunately, none of these studies compared different holding media along with different holding times. Certainly, holding medium quality would enter into this issue as perhaps would temperature if it was highly elevated.

If I was still directly involved with freezing embryos commercially, I would feel most comfortable sticking to a 3-4 hr maximum holding time (in a commercial holding medium) whenever possible. However, a few more hours in holding medium might lower subsequent pregnancy rates but probably would not lead to a ‘disaster’.

References

Coley, Stanley L. 1987. Improving pregnancy rates from frozen embryos. Proceedings of the 6th Annual Convention of the AETA, Orlando, Florida. pp.40-50

Hasler, John F.  2001. Factors affecting frozen and fresh embryo transfer pregnancy rates in cattle. Theriogenology 56:1401-1415.

Jousan, F.D., Utt, M.D., Whitman, S.S., Hinshaw, R.H. and Beal, W.E. 2003. Effects of varying the holding temperature and interval from collection to freezing on post-thaw development of bovine embryos in vitro. Theriogenology 61:1193-1201.

Otter, T. 1994. Pregnancy rate of fresh and frozen-thawed cattle embryos. Proceedings of the 10th Scientific Meeting of the European Embryo Transfer Association (AETE), Lyon, France. pp.228.

Practice Tip: Freezing matings with various stages/grades

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Published on: December 21, 2012

In our system we place straws containing embryos in Ethylene Glycol (EG) into the freezer 5 minutes after they are transferred into EG from holding media.  During this 5 minute equilibration time, the embryos are loaded into straws and sealed with plastic straw tops.  On larger double digit matings with embryos of various stages and grades, it can be a challenge to find, identify, and load each embryo into the corresponding straw within this time frame as the embryos spread out into “chaos” when they go into EG.  One efficiency trick our embryologists have found is to presort the embryos into stage/grade groups while still in the final holding well and load the transfer pipette in groups with a little fluid and/or air space separating each group.  This allows one to dispense the embryos into the EG dish one group at a time and in separate areas of the dish to keep embryos of the same stage/grade together.  Essentially, this takes the “chaos” out of the process and eliminates one from having to take precious seconds to decipher whether an embryo was a 5-1 or 5-2, etc.  It also reduces anxiety as the timer ticks away on its way to 5 minutes.

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