AETA President’s Report – Summer 2021

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Published on: August 18, 2021

The challenge of a long winter is finally over. It seems, however, that as one challenge winds down, others arise. As the significance of the pandemic subsides, other challenges manifest, such as labor shortages and hiccups in the commodity markets. Consolidation of farms creates both a disruption to the status quo and opportunity at the same time. Warm temperatures bring the flush of spring pasture and also the rear ends of recipient cows capable of filling your pocket with a slimy effluent. We take the good with the bad.

To say the past year has been a challenge would be stating the obvious.  Despite the progress made in dealing with the COVID-19 pandemic, there are still unresolved issues, one of which is international travel.  The AETA Board, along with CETA, tried to navigate this storm, but we were unable to proceed with an in-person convention due to the uncertainty surrounding the opening of the US-Canada border.  As a result, both AETA and CETA elected to forgo an in-person convention for 2021 in favor of another virtual meeting.  The meeting format will be similar to that in 2020 but will be hosted by CETA with the help of FASS and AETA.  The program that CETA is assembling is coming together, and we have a preliminary speakers list posted on the AETA website.

The AETA also faces the challenge of recruiting and retaining new members. The AETA Certification “brand” is something in which all certified members should take pride. The AETA-certified practitioner status is not only a source of pride, but also a designation that ensures competency. Unfortunately, many cattlemen do not appreciate or understand the significance of the AETA certification or the educational opportunities available to both certified and non-certified members through our association. We feel that for the AETA to remain relevant and grow, the AETA brand and certification have to grow.

We have had success in offering continuing education opportunities to professionals and, along with that, complimentary membership for a year. The student scholarship program has also helped with recruiting new members, but there is more that we can do.

Many of our clients are large players in the embryo transfer field, and we feel they would benefit from AETA regular membership. On more and more farms, on-farm labor is used to transfer embryos, both fresh and cryopreserved. The educational opportunities and networking opportunities offered by the AETA could elevate both professionals and their clients. Breed associations such as Holstein and American Angus could also benefit from associate membership.

The true significance of AETA certification has yet to be discovered by the mainstream of the embryo transfer world. This process needs to happen, yet it will only happen slowly and deliberately. We recently had stickers printed with the AETA Certified logo that will be distributed to certified members. These stickers can and should be placed anywhere that it would cause a client to ask about what AETA certification is. Finally, we also need to continue to increase our exposure to the veterinary and animal science communities.

One of the most recent challenges we met were the new European Union (EU) import regulations on both conventional and IVP embryos. Ashley Swenson and the entire Government Liaison Committee in cooperation with the United States Department of Agriculture (USDA) navigated these troubled waters like true professionals, providing clarity and taking a strong stand on behalf of US embryo transfer professionals and producers alike. While the changes in the paperwork requirements will take a little time to get used to, the transition to the new regulations has happened already. Unfortunately, it appears as though the number of sires available to be used in the production of IVF embryos eligible for EU export will decrease as a result of the new regulations.

Challenges will continue; they always do. Challenges become opportunities when met head on. Stay safe, be well, and keep the green effluent away from your pockets.

Dr. Bill Croushore – AETA President

Register now for the 2021 AETA-CETA/ACTE Joint Annual Virtual Meeting!

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Published on: August 18, 2021

The 2021 AETA-CETA/ACTE Joint Annual Meeting will be held virtually beginning on October 15. You must register before October 15 to get access to the live virtual meeting. Register now!

All of the scientific, sponsor, and continuing education (CE) information can be found on the AETA Annual Convention page as it becomes available. Check back often!

For the price of US$200, registrants will be able to access the meeting content until December 31. Register before October 15 to join us for the live virtual meeting. Registration will reopen after the live meeting from October 17 to December 1, and registrants will have access to the convention recordings and CE quizzes until the end of the year.

Prerecorded sessions will be made available via a link on the AETA convention page at 12:01 a.m. (CDT) on Friday, October 15. During the times on the schedule, speakers will be available to chat via Zoom about their presentations and answer any questions you may have.

All sessions will have a quiz that participants must participate in and pass with a score of at least 70% to receive CE credits.

Please note that speakers will only be available for discussion during their scheduled time on either October 15 or 16.

We look forward to seeing you in October!

2021 AETA-CETA/ACTE Joint Annual Virtual Meeting Scientific Schedule

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Published on: August 18, 2021

All times listed are central daylight time

Friday, October 15

12:01 AMAll pre-recorded sessions available for viewing
8:45 AM – 9:00 AMWelcome & Sponsor Announcements
9:00 AM –10:10 AMSession 1: Strategies to simplify in vivo and in vitro embryo
production in beef donors; competing or complementary techniques?

Presented by Dr. Gabriel Bo
10:10 AM – 12:00 PMAETA Session
10:10 AM – 12:00 PMCETA/ACTE Annual General Meeting
12:00 PM – 1:10 PMSession 2: Complications associated with equine transvaginal ultrasound-guided follicle aspiration

Presented by Dr. Katrin Hinrichs
1:10 PM – 2:20 PMSession 3: Disease control around Embryo Transfer

Presented by Dr. François-Xavier Grand
2:20 PM – 3:30 PMSession 4: Control of the estrous cycle among embryo transfer recipients using the 7&7 Synch protocol

Presented by Dr. Jordan Thomas
3:30 PM – 4:40 PMSession 5: Gametes and embryos from stem cells: status and applications in
animal reproduction


Presented by Dr. Pablo Ross
4:40 – 5:50 PMSession 6: Periconceptual environment impact on gametes and embryo epigenetic legacy

Presented by Dr. Marc-André Sirard
5:50 PMDay 1 closing remarks

Saturday, October 16

8:45 AM – 9:00 AMWelcome and Sponsor Announcements
9:00 AM – 10:40 AMSession 7: OPU and lab considerations in providing IVF services

Presented by Dr. Jon Schmidt & Patti Anderson, MS
10:40 AM – 11:50 AMSession 8: Calves from calves: accelerating genetic advancement

Presented by Dr. Hernan Baldassarre
12:00 PM – 1:00 PMAETA Business Meeting (election of new officers)
12:00 PM – 1:00 PMCETA/ACTE New Board of Directors
1:10 PM – 2:20 PMSession 9: Practitioners Forum

Embryo Debris: Presented by Dr. Gabriel Couto

Practitioner Challenges: Preparing for IVF Transfer Day: Presented by Dr. Brad Lindsey

Fresh IVF transfer on Day 6.5 post fertilization: Presented by Dr. Cody Bailey
2:20 PM – 3:30 PMSession 10: Small Ruminants

Presented by Dr. Tad Thomson
3:30 PM – 4:40 PMSession 11: Progesterone supplementation: When does it increase reproductive efficiency
in cattle?

Presented by Dr. Angelika Stock
4:40 PM – 5:50 PMSession 12: The cow’s genital tract in postpartum period: Update

Presented by Dr. Réjean Lefebvre
5:50 PMConvention Closing Remarks and BOD Election Results

2021 Candidates for the AETA Board of Directors

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Published on: August 18, 2021

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2021 AETA Certification Exam and Practicum

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Published on: August 18, 2021

Those seeking to sit for the 2021 AETA Certification Exam and Practicum will still be able to voluntarily do so this year at the Iowa State University (ISU) College of Veterinary Medicine in Ames, Iowa, on Saturday, September 25, in person, pending approval of their application. The exam will begin at 8:00am central time and more information on the exact location at ISU will be made available soon.

All applications to sit for the exam must be received no later than Wednesday, September 1.

Please visit the AETA Certification guidelines for more information on how to complete and submit your application.

Sincerely,

The AETA Certification Committee

Webinar series: Strategies for Control of Estrous Cycles of Beef Heifers & Cows

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Published on: August 18, 2021

The University of Missouri’s National Center for Applied Reproduction and Genomics is hosting a webinar series that focuses on control of the estrous cycle in beef heifers and cows.  The series begins on Thursday, September 2nd with a one-hour presentation on the bovine estrous cycle and products approved for control.  Additional topics will be offered each Thursday evening throughout the month and include estrous synchronization programs for replacement heifers, postpartum cows, and cows managed as recipients in embryo transfer programs.  The series concludes on September 30th with a presentation on assessing synchronization program efficacy and identifying possible problems when outcomes do not meet expectations.  The program has been submitted (but is not yet approved) for 5 hours of continuing education credit in jurisdictions that recognize RACE approval.  There is no cost to participants and further information/registration can be accessed here: https://cvent.me/M8A4dK. All presentations will be recorded and available shortly after the conclusion of the series. 

Disappearance and uptake of [125I]FSH in the rat, rabbit, ewe and cow

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Published on: August 18, 2021

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D. B. LasterUSDA

Date of this Version

1972

Comments

Published in J. Reprod. Fert. (1972) 30, 407-415

Abstract

Follicle-stimulating hormone (NIH-FSH-S8) was labelled with 125I to determine its disappearance rate after a single intravenous injection and to determine the level of circulating [125I]fsh in the blood after a single intramuscular or subcutaneous injection in the rat, rabbit, ewe and cow. There was a difference in the disappearance and uptake rates among the four species, but the shape of the curve for rate of loss and uptake of labelled fsh was similar in all species. The disappearance of radioactivity occurred at two rates; the first from 1 to 8 min and the second from 16 to 96 min. The half-life, calculated from the total decay curve in each species was 94±21, 118±16, 334±41 and 301±23 min for the rats, rabbits, ewes and cows, respectively. Intramuscular injections resulted in an average of 56% higher [125I]fsh blood levels than subcutaneous injections for all species.

Embryo Transfer in Cattle

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Published on: August 18, 2021

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Reproductive Physiology Review

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Published on: August 18, 2021

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In Vitro Fertilization in Cattle

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Articles of Interest

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Published on: August 18, 2021

https://www.animal-reproduction.org/article/5b5a604bf7783717068b46a0

https://www.journalofdairyscience.org/article/S0022-0302(19)30635-6/fulltext

https://www.animal-reproduction.org/article/doi/10.21451/1984-3143-AR1002

https://www.semanticscholar.org/paper/Artificial-Insemination-and-Embryo-Transfer-in-Farin/da20551c1a0fad2bafd1dd931de027691a6bebe0

https://www.sciencedirect.com/science/article/pii/S0022030201746905

https://www.mdpi.com/2076-2615/11/6/1666/htm

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830735/

https://www.sciencedirect.com/science/article/pii/S0022030208712153

https://rep.bioscientifica.com/view/journals/rep/154/6/REP-17-0357.xml

AETA President’s Report – Winter 2021

Categories: President's Message
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Published on: February 18, 2021

Greetings,

I’d like to first introduce myself to those who don’t know me. I am a partner in White Oak Veterinary Clinic, PC, in Somerset County, Pennsylvania. I have been a member of AETA for 10 years and certified since 2012.

I thank Matt Dorshorst, our immediate past president, for his excellent guidance through a difficult 2020 and our departing board members, Matt Iager and Kory Bigalk. Congratulations to Clay Breiner, who will serve as vice president, and Greg Schueller, who will serve as secretary-treasurer.

Besides the (hopefully) temporary challenges we face from the COVID-19 pandemic, our industry also faces some significant challenges in the near future. With the consolidation of the dairy industry and low beef prices, the traditional model of embryo transfer may be facing some challenges. Some people believe that the bovine embryo is becoming commoditized. My primary goal as president of the AETA this year will be to set the association on a path to help its members deal with these challenges. The high standards required by AETA certification are, I believe, a hedge against commoditization. Our industry, like many others, is changing and being disrupted by newer technology. We should not fear disruption, but instead find a way to adapt.

During our mid-winter board meeting, we will troubleshoot and brainstorm ways to meet these challenges. And if there are any issues you think the board should address, please don’t hesitate to reach out to me.

Sincerely,

Bill Croushore

Letter from AETA Past President

Categories: President's Message
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Published on: February 18, 2021

I have had the honor to work on your behalf for the last four years. This last year as your president has been a memorable one for me. I could not have managed the personal as well as professional challenges of 2020 without the support of the AETA board and our members. Thank you!

I made several observations while on the AETA board over the last year that were relevant as we dealt with the challenges of 2020. I suspect they are also important for success going forward. The AETA board functioned well because they listened patiently to a variety of ideas related to a problem or concept. As we made decisions, board members showed empathy and tolerance for the varied opinions expressed by their colleagues. The open-mindedness of the board to identify and adapt to challenges was impressive and made the virtual conference and other aspects of AETA business a success.

Although these characteristics served the 2020 board and the AETA well, I suspect they are important in all matters we face as individuals, businesses, families, and society. As we reflect on the year 2020, I hope we all consider the importance of listening with patience, showing empathy and tolerance, and adapting to change. Perhaps it will help make 2021 exactly what we are all hoping for.

Thank you again for the privilege to serve you.

Sincerely,

Matthew Dorshorst, MS, DVM

Dr. Joe Oden

Categories: Board of Directors
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Published on: February 18, 2021

Dr. Joe Oden, AETA past president (1988–1989), sadly passed away on January 15, 2021.

Dr. James Spears shared that he recalled Oden assisting in administering the very first AETA certification exam in Louisville in 1984, with Oden administering Spears’ certification test. He also said that Oden was one of the first practitioners involved in ET at one of the first ET centers – Codding Reproductive Services in Pawhuska, Oklahoma.

Below is Dr. Oden’s obituary:

Joe “Dr. Joe” Oden was a man of deep, abiding strength and faith. His feet were firmly planted
on the earth and in the beauty of God’s creation while striving to have his eyes and heart set on the heavenly treasures awaiting him. Throughout his life, God guided him as he learned that the greatest treasures are to be found in the simplicity of God’s kingdom of love and mercy.

Joe was born and raised near Brownwood, Texas, with his older sister, the late Bettye Sue Oden
Connaway, and his adoring parents, also in Glory, Anson and Dorine McMurray Oden. Together they were a well-known and respected farming family in Brown County. Besides helping with farm chores and riding his favorite paint horse, Streak, Joe loved all kinds of sports that he excelled in throughout his school years at Brooksmith High School, graduating in 1959. He went on to attend Tarleton State in Stephenville, Texas, for two years, serving in the corps of cadets as a member of the Wayneright Rifle Squad drill team as well as having had the honor of marching in Washington D.C. for the inaugural parade of John F. Kennedy.

College Station is where he met, fell in love with, and married Marcia Ransom Oden, his sweetheart of 56 years. God gave them two children, Anson Joseph III (Trey) and Cindy Renee.

Joe went on to attend Texas A&M University (TAMU) to obtain a BS degree in agricultural education and then continued his graduate studies in education. He followed the call to continue on to TAMU Large Animal Veterinary School while in graduate school and was grateful to the many mentors along his way. Joe graduated from veterinary school in 1969. His interest in the science and practice of embryo transfer in cattle over the years took the family from Texas to Oklahoma and then for four years to the hills of Tennessee, where they all thrived in the beautiful, abundant gardens he created there with the family. Joe taught in both vet schools, TAMU and University of Tennessee.

They returned to Texas, where Joe was employed with Granada Land and Cattle Company for 10 years, glad to return to his home state and his family along with some truly wonderful friendships that he cherished. He then began his own embryo transfer business (Old Spanish Trail Genetics) with some of his colleagues. He served some time as president of the American Embryo Transfer Association (AETA), being one of the leaders and pioneers in the field of genetics.

He was a brilliant yet humble man and easy to love. In his later years, his time and attention turned toward family, golfing, and his home in Normangee, where he and Marcia were members of Sand Prairie Baptist Church. Naturally, Joe’s focus became more reflective seeking to know his Lord Jesus Christ in a deeper and richer way. His mealtime prayers were not to be missed, a window into a beautiful and peaceful heart.

Whether laboring for his father in the fields under a hot Texas sun, serving his family and friends with his quick-witted humor and hard, honest work ethic, or telling stories from his upbringing as a simple farm boy with lofty dreams, his life showed how one can attain to greatness in a worldly sense while quietly and steadily nurturing the seeds of eternal life and glory within. Thank you, Joe Oden, for walking this earth and making it brighter, funnier, and more real with every breath and every step.

Joe is survived by his adoring wife, Marcia Ransom Oden; their two children, Trey and Cindy, along with their spouses, Gynger and Jasper; as well as Gynger’s children, Kaylee and Kiley.

Joe had three grandsons, Zachary Oden, Samuel Oden Warren, and Nicolas Oden. He is also survived by Zach and Nic’s mother, Dawn Pisani Oden. Joe had one great-granddaughter, Aspen Jade Oden, through Zach and his wife, Sandra; by his nephew, John Connaway, and his wife, Laura, and their son, Brian Connaway, with his wife, Marla; Wanda Connaway, wife of his dear friend and brother-in-law, the late Delbert Connaway; cousin Katherine Newell and her husband, Phillip; Marva Brim, wife of the late Jim Brim, Joe’s dear friend and first cousin; Marcia’s brother, Henry Ransom, his wife, Jane, and their children: Jordan, with his wife, Stefani ,and their children, Nicole and Rachel Ransom; and Justin, with his wife, Stephanie, and their children, Bella and Eloise Ransom. He is also survived by numerous friends and loved ones from along his life journey. You know who you are. Thank you all for contributing to a life well lived.

https://www.hillierfuneralhome.com/tributes/Anson-JosephJoeOdenJr

Ask a question to an AETA certified ET practitioner

Categories: Catching Up, Practice Tips
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Published on: February 18, 2021

By Pat Comyn

Ask an ET-related question. An AETA-certified practitioner will answer!

Here’s one I asked Dr. Reuben Mapletoft to answer regarding proper or best thaw temperature for direct thaw (DT) embryos.

Question: Reuben, is there any data that support a 28 to 29°C thaw versus a 35 to 37°C thaw? I see that Japanese papers and the Food and Agriculture Organization of the United Nations recommend 37°C. And how about a 5-s air thaw versus right in bath? It seems to me that cracked zona concerns are a question mark as it hopefully cracks anyhow.

Answer: You are correct; with a direct transfer a cracked zona is probably even preferred. The air thaw is only important for glycerol where it is important to be able to find the embryo.

We looked at several thaw temperatures between 25 and 35°C several years ago and found no difference in survival. I suppose you argue that perhaps you should be thawing near environmental temperature, but I think it is important to thaw quickly. Having said that, thaw rate to 0°C is probably the same for all temperatures, so then the thaw temperature really determines where it ends up.

Reuben J. Mapletoft

Distinguished Professor Emeritus

Department of Large Animal Clinical Sciences

Western College of Veterinary Medicine

University of Saskatchewan Saskatoon, SK S7N 5B4 

Equine chorionic gonadotropin increases estradiol levels in the bovine oviduct and drives the transcription of genes related to fertilization in superstimulated cows

Categories: Research Publications
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Published on: February 18, 2021

Patricia K Fontes 1Eduardo M Razza 1Antônio G R Pupulim 2Ciro M Barros 1Anthony C de Souza Castilho 3

1Departament of Pharmacology, Institute of Biosciences, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo, Brazil.

2Centro Universitário Cesumar (UNICESUMAR), Maringá, Paraná, Brazil.

3Universidade do Oeste Paulista (UNOESTE), Presidente Prudente, São Paulo, Brazil.

https://pubmed.ncbi.nlm.nih.gov/31353672/

Mol Reprod Dev. 2019 Nov;86(11):1582-1591. doi: 10.1002/mrd.23243. Epub 2019 Jul 29.

Abstract

In the bovine oviduct, estradiol (E2) stimulates secretion and cell proliferation, whereas progesterone (P4) suppresses them. In this study, we have evaluated the effect of two superstimulatory protocols (follicle-stimulating hormone [FSH] or FSH combined with equine chorionic gonadotropin [eCG]) on the oviductal levels of E2 and P4 and its outcome on oviductal cells. Compared with the control group (a single pre-ovulatory follicle), we have observed that the cows submitted to FSH/eCG treatment showed a higher concentration of E2 in the oviduct tissue, together with a higher abundance of messenger RNA encoding steroid receptors (ESR1 and progesterone receptor), and genes linked to gamete interactions and regulation of polyspermy (oviduct-specific glycoprotein 1, heat-shock protein family A member 5, α-l-fucosidase 1 [FUCA1], and FUCA2) in the infundibulum and ampulla segments of the oviduct. However, we did not observe any modulation of gene expression in the isthmus segment. Even though the FSH protocol upregulated some of the genes analyzed, we may infer that the steady effect of FSH combined with eCG on oviduct regulation might benefit fertilization and may potentially increase pregnancy rates.

Keywords: cattle; female reproductive tract; gametes; gene expression; steroids; superovulation.

Effect of superstimulation on the expression of microRNAs and genes involved in steroidogenesis and ovulation in Nelore cows

Categories: Research Publications
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Published on: February 18, 2021

P H Santos 1R A Satrapa 2P K Fontes 1F F Franchi 1E M Razza 1F Mani 3M F G Nogueira 4C M Barros 1A C S Castilho 5

1Universidade Estadual Paulista (UNESP), Institute of Biosciences, Campus Botucatu, Department of Pharmacology, Botucatu, São Paulo, Brazil.

2Universidade Federal do Acre (UFAC), Center of Biological and Natural Sciences, Rio Branco, Acre, Brazil.

3Universidade Estadual Paulista (UNESP), Institute of Biosciences, Campus Botucatu, Department of Chemistry and Biochemistry, Botucatu, São Paulo, Brazil.

4Universidade Estadual Paulista (UNESP), School of Sciences and Languages, Campus Assis, Department of Biological Sciences, Assis, São Paulo, Brazil.

5Universidade Estadual Paulista (UNESP), School of Sciences and Languages, Campus Assis, Department of Biological Sciences, Assis, São Paulo, Brazil. Electronic address: anthony@unoeste.br.

https://pubmed.ncbi.nlm.nih.gov/29407901/

Theriogenology 2018 Apr 1;110:192-200. doi: 10.1016/j.theriogenology.2017.12.045. Epub 2018 Jan 11.

Abstract

To better understand the impact of ovarian superstimulation on bovine follicular microenvironment, Nelore cows (Bos taurus indicus) were subjected to ovarian superstimulation with follicle stimulating hormone (FSH, n = 10; P-36 protocol) or FSH combined with eCG (n = 10; P-36/eCG protocol). Follicular fluid was analyzed for cholesterol concentration. Granulosa cells were analyzed by RT-qPCR to assess the expression of genes involved in steroidogenic and ovulatory and expression of microRNAs involved in final follicular development and luteinizing hormone/choriogonadotropin receptor (LHCGR) expression. Plasma concentration of estradiol was also measured. Follicular fluid from the P-36 group showed higher concentration of cholesterol than that of control (non-superstimulated) cows. Plasma concentration of estradiol was higher in the P-36/eCG group. Abundance of STAR and FSHR mRNAs were lower in granulosa cells from the P-36/eCG group. In contrast, LHCGR mRNA abundance was higher in superstimulated granulosa cells from the P-36 group and showed a pattern opposite to that of miR-222 expression. Ovarian superstimulation did not affect the expression of other markers (mmu-miR-202-5p, has-miR-873, has-miR-144, and their target genes, CREB, TGFBR2, and ATG7) of antral follicle development. However, the mRNA expression of VEGF pathway components was modulated by P-36 treatment. Taken together, these results demonstrate that superstimulatory protocols modify steroidogenic capacity, increase plasma estradiol, and regulate the abundance of VEGF system, LHCGR mRNA and suppress the expression of miR-222 in bovine granulosa cells.

The incompletely fulfilled promise of embryo transfer in cattle—why aren’t pregnancy rates greater and what can we do about it?

Categories: Research Publications
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Published on: February 18, 2021

Peter J Hansen

Department of Animal Sciences, D.H. Barron Reproductive and Perinatal Biology Research Program, and Genetics Institute, University of Florida, Gainesville, FL

https://academic.oup.com/jas/article/98/11/skaa288/5954183

Journal of Animal Science, Volume 98, Issue 11, November 2020, skaa288 https://doi.org/10.1093/jas/skaa288

Abstract

Typically, bovine embryos are transferred into recipient females about day 7 after estrus or anticipated ovulation, when the embryo has reached the blastocyst stage of development. All the biological and technical causes for failure of a female to produce a blastocyst 7 d after natural or artificial insemination (AI) are avoided when a blastocyst-stage embryo is transferred into the female. It is reasonable to expect, therefore, that pregnancy success would be higher for embryo transfer (ET) recipients than for inseminated females. This expectation is not usually met unless the recipient is exposed to heat stress or is classified as a repeat-breeder female. Rather, pregnancy success is generally similar for ET and AI. The implication is that either one or more of the technical aspects of ET have not yet been optimized or that underlying female fertility that causes an embryo to die before day 7 also causes it to die later in pregnancy. Improvements in pregnancy success after ET will depend upon making a better embryo, improving uterine receptivity, and forging new tools for production and transfer of embryos. Key to accelerating progress in improving pregnancy rates will be the identification of phenotypes or phenomes that allow the prediction of embryo competence for survival and maternal capacity to support embryonic development.

‘There is only one thing that is truly important in an IVF laboratory: everything’ Cairo Consensus Guidelines on IVF Culture Conditions

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Published on: February 18, 2021

Cairo Consensus Group

https://www.sciencedirect.com/science/article/pii/S1472648319307540#!

Reproductive BioMedicine Online Volume 40, Issue 1, January 2020, Pages 33-60

Abstract

This proceedings report presents the outcomes from an international expert meeting to establish consensus guidelines on IVF culture conditions. Topics reviewed and discussed were: embryo culture – basic principles and interactions; temperature in the IVF laboratory; humidity in culture; carbon dioxide control and medium pH; oxygen tension for embryo culture; workstations – design and engineering; incubators – maintaining the culture environment; micromanipulation – maintaining a steady physcochemical environment; handling practices; assessment practices; culture media – buffering and pH, general composition and protein supplementation, sequential or single-step media for human embryo culture; use and management – cold chain and storage; test equipment – calibration and certification; and laboratory equipment and real-time monitoring. More than 50 consensus guideline points were established under these general headings.

Keywords: Culture conditions, Incubators, IVFMaintenance, Medium, Quality control

Direct transfer of frozen-thawed bovine embryos and its application in cattle reproduction management

Categories: Research Publications
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Published on: February 18, 2021

Osamu DOCHI1

1)Rakuno Gakuen University, Hokkaido 069-0851, Japan

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6815740/

J Reprod Dev. 2019 Oct; 65(5): 389–396.Published online 2019 Jun 13. doi: 10.1262/jrd.2019-025

Abstract

Embryo transfer entails many procedures and techniques, of which embryo freezing is an important component in bovine embryo transfer. Embryo freezing techniques have been developed over the last 40 years, allowing practical availability, and have become essential for cattle reproduction management under field conditions. The direct transfer methods of frozen-thawed, in vivo-derived, and in vitro-produced (IVF) bovine embryos using 1.5 M ethylene glycol (EG) with or without sucrose (SUC) are used widely under on-farm conditions, not only in Japan but also globally. The direct transfer method using 1.5 M glycerol (GLY) and 0.25 M SUC (GLY-SUC) is used mainly in Japan. The pregnancy rate with direct transfer of frozen-thawed bovine embryos in either EG or GLY-SUC has been found to not differ from conventional freezing with GLY and traditional dilution techniques. Pregnancy rates following direct transfer of frozen-thawed bovine embryos were affected by the developmental stage of the embryos and the parity of the recipients. The use of ultrasound-guided on-farm ovum pickup is ushering in a new revolution for the commercial application of IVF embryos. Globally, for the first time more IVF bovine embryos were transferred in 2017 than produced in vivo. More than 60% of IVF embryos were transferred fresh due to a low pregnancy rate of frozen-thawed IVF embryos. Many factors seemed to be involved in improving the survival rate of frozen-thawed IVF embryos. Therefore, further research is needed to improve the freezing tolerance of IVF embryos to develop efficient direct transfer methods analogous to those used for in vivo embryos.

Keywords: Bovine embryo, Direct transfer, Ethylene glycol, Freezing, Pregnancy rate

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