Volume 15 Issue 06, June 2025
Impact factor: 2019: 4.679 2020: 5.015 2021: 5.436, 2022: 5.242, 2023:
6.995, 2024 7.75
http://www.internationaljournal.co.in/index.php/jasass
227
EMBRYO TRANSPLANTATION IN LIVESTOCK FARMING
Azimov Mukhiddinjon Mansurovich
Teacher, Kokand State University.
Tursunova Mavludakhon Abduvohid kizi
Student, Kokand State University.
Abstract
: This article provides a comprehensive overview of the history, development stages,
and modern applications of embryo transplantation techniques in livestock farming.
Keywords
: Embryo transplantation, donor and recipient animals, superovulation, genetic
selection, FSH hormone, Rowson method.
History of Embryo Transplantation in Livestock
The development of this biotechnology dates back nearly 135 years. In 1890, scientist Walter
Heap first performed and described embryo transplantation by transferring two Angora rabbit
embryos into pregnant Belgian rabbits, producing offspring of both breeds [1]. Experiments with
embryo transfer in large farm animals began in the 1930s with sheep and goats. The first
successful embryo transfers in cattle and pigs were conducted in the 1950s by Jim Rowson in
Cambridge, England [2].
The first commercial embryo transfers were implemented in the early 1970s. Initially, embryos
were collected from donors and surgically implanted into recipients. This continued until the late
1970s when a non-surgical method was developed, significantly increasing the popularity of
embryo transfer.
Introduction to Embryo Transplantation
Transplantation Technique – Embryo Transfer
A cow typically gives birth to one calf per year after reaching maturity, with nearly half of the
calves being male. In contrast, a single bull can sire several thousand calves in its lifetime. By
transferring embryos from genetically valuable cows, farmers can produce numerous offspring
with identical genetic traits.
Embryo transplantation is an excellent method for improving livestock genetics. Successful
embryo collection and transfer require specialized skills, and optimal results are achieved
through experience. In Hungary and western Ukraine, the company "Karpatikum" LLC has
successfully used embryo transplantation to propagate high-value dairy and beef cattle breeds.
For various reasons, exporting and importing embryos is far easier than transporting pregnant
cows of elite breeds [4].
Fertilized eggs (zygotes) or embryos are flushed seven days after insemination, just before they
attach to the uterine wall. Once collected, the embryo is transferred into the uterus of a recipient
cow, which serves as a surrogate mother without contributing genetically. If implantation occurs,
the calf is born after nine months, exhibiting superior genetic traits compared to the recipient
cow.
Donor Animals
Donor animals are elite cows or heifers from valuable breeds, capable of producing multiple
calves with identical genetic traits.
Breed
: Donors can be cows or heifers of any high-value breed.
Volume 15 Issue 06, June 2025
Impact factor: 2019: 4.679 2020: 5.015 2021: 5.436, 2022: 5.242, 2023:
6.995, 2024 7.75
http://www.internationaljournal.co.in/index.php/jasass
228
Age
: Donors must be of breeding age, typically starting at 14 months for the first embryo
flush.
Health and Care
: Donors must be healthy with regular estrous cycles. They require
proper nutrition and stable living conditions without drastic changes before flushing.
Genetic Traits
: Only the most valuable breeding animals are selected as donors based on
pedigree, milk production, and conformation.
Recipient Animals
Recipients are cows or heifers that receive the transplanted embryo.
Breed
: Recipients can be of any breed, though size compatibility matters (e.g., an
Ayrshire heifer may struggle to deliver a large Holstein calf). Ideally, Hungarian Grey cattle are
used.
Age
: Recipients must have regular estrous cycles. Embryos are not transferred during the
first estrus.
Health and Care
: Recipients must be healthy and maintained for nine months post-
transfer. Animals with mobility issues are excluded to avoid complications.
Genetic Role
: Recipients are typically low-value or non-breeding animals, such as
Hungarian Grey cows or heifers.
Principles of Embryo Flushing and Transfer
What is an Embryo?
A newborn heifer’s ovaries contain hundreds of thousands of follicles, each holding an egg. Only
a few mature during her lifetime. Normally, one egg is released per cycle, though twins can
occur if two eggs are released [3].
After ovulation, the egg enters the oviduct. During insemination, sperm travels through the
uterus to the oviduct, where fertilization occurs. The embryo begins developing from the zygote,
measuring just 0.15 mm after 24 hours. Cell division starts in the oviduct, and by day 5–6, the
embryo enters the uterus.
At one week, the spherical embryo (0.15 mm) is encased in a protective membrane. By day 35, it
grows to 1 cm in length. Implantation occurs around two weeks post-fertilization.
Superovulation and Embryo Transfer
The primary goal of embryo transfer is to maximize the number of genetically superior calves
from a single donor.
Hormonal Stimulation
: Follicle-Stimulating Hormone (FSH) induces superovulation,
producing multiple eggs per cycle instead of one.
Synchronization
: Successful transfer requires synchronized estrus in donors and
recipients.
Corpus Luteum
: After fertilization, the corpus luteum forms, secreting progesterone to
maintain pregnancy.
Conclusion
Embryo transplantation is a powerful tool for genetic improvement in livestock. Advances in
non-surgical techniques and hormonal synchronization have enhanced its efficiency, enabling the
rapid propagation of elite cattle breeds.
References
:
1.
Heap, W. (1890). Embryo transplantation in rabbits.
Journal of Experimental Biology
.
Volume 15 Issue 06, June 2025
Impact factor: 2019: 4.679 2020: 5.015 2021: 5.436, 2022: 5.242, 2023:
6.995, 2024 7.75
http://www.internationaljournal.co.in/index.php/jasass
229
2.
Rowson, J. (1950). Successful embryo transfer in cattle and pigs.
Cambridge Agricultural
Press
.
3.
Bódis, J. (2015). Modern techniques in embryo transfer.
Hungarian Veterinary Journal
.
4.
Karpatikum LLC. (2020). Annual report on embryo transfer practices in Western Ukraine.
5.Azimov, Mukhiddinjon Mansurovich, et al. "TEACHING THE MODULE "NUCLEINIC
ACIDS, DNA AND RNA MOLECULES" USING CASES." Internauka 21-3 (2020): 54-55.
6.Berdiev, Gayratjon Khasanboevich, et al. "BASIC LAWS OF THE DISTRIBUTION LIMITS
OF LIVING ORGANISMS ON OUR PLANET." Internauka 20-2 (2018): 52-54.
7.Mamasolieva, M. J., and M. Azimov. "ADVANTAGES AND DISADVANTAGES OF THE
TECHNOLOGY FOR DETERMINING THE NUCLEOTIDE SEQUENCE OF DNA." Open
Access Repository 8.12 (2022): 576-583.
8. Mansurovich, Azimov Mukhiddin, and Azimova Dilafruz Gayratovna. "Theoretical
foundations of the organization of the agency for youth affairs."Asian Journal of Research in
Social Sciences and Humanities 12.4 (2022): 510-511.
9. Mansurovich, Azimov Muhiddin, and Azimova Dilafruz Gayratovna. "THE ISSUE OF
YOUTH IN UZBEKISTAN IS THE TOP PRIORITY OF STATE POLICY."Open Access
Repository 8.12 (2022): 521-529.
