APPLICATION OF EMBRYO TRANSFER TECHNOLOGY TO IMPROVE MILK YIELD IN DAIRY CATTLE IN INDIA
Also called as Multiple Ovulation and Embryo Transfer (MOET) Technology, is used to increase the reproduction rate of superior female dairy animals. Normally, one can get one calf from a superior female dairy animals in a year. But by using MOET technology, one can get 10-20 calves in a year from a cow/buffalo. An elite cow/buffalo is administered hormones with FSH-like activity to induce super-ovulation. Under the influence of the hormone, the female produces several eggs instead of one egg produced normally. The super-ovulated female is inseminated 2-3 time at 12 hour interval during estrus and then its uterus is flushed with a medium 7th day post insemination to retrieve the developing embryos. Embryos are collected along with flushing medium in a specialised filter and the quality of embryo is assessed under the microscope. Good quality embryos either frozen and preserved for transfer in future or transferred fresh into recipient animals approximately seven days post heat date. Thus, from an elite dairy animal several calves can be produced in a year.
The first embryo transfer technology (ETT) project in the country was initiated by NDDB in 1987 by establishment of a central ET laboratory at Sabarmati Ashram Gaushala (SAG), Bidaj. The project was funded by the Dept. of Biotechnology (DBT), Ministry of Science & Technology, GoI for 5 years (April 1987 – March 1992). Under this project, NDDB established one Main ET Lab at SAG Bidaj and four Regional ET Labs at CFSP&TI, Hessarghatta (Karnataka), ABC, Salon (UP), Shri Nashik Panchavati Panjrapole, Nashik (Maharashtra) and Buffalo Breeding Centre, Nekarikallu (AP). NDDB also assisted in establishment of 14 State ET centres across the country.
SAG has done pioneering work in this field and has so far produced 14388 viable embryos and 755 calves, which is highest by any organisation in the country. Of these, 1026 embryos are of indigenous cattle breeds, from which 122 calves have been born. Besides these, around 3000 embryos of buffalo breeds have also been produced. Under the project, the first buffalo calf of India from frozen thawed embryo was born in the year 1991.
What is ET?
Embryo transfer is a technique by which embryos are collected from a donor female and are transferred to recipient females, which serve as surrogate mothers for the remainder of pregnancy. Embryo transfer techniques have been applied to nearly every species of domestic animal and to many species of wildlife and exotic animals, including humans and non-human primates. Within the past decade the degree of sophistication of embryo transfer procedures has evolved to permit complete utilization of non-surgical procedures in the cow, long term embryo culture and storage with cryopreservation, and, more recently, micromanipulation and many techniques associated with genetic engineering. This is a rapidly developing science with a very short lag-time between discovery and application. The potential applications continue to increase with the development of new technology.
The first ET project ‘Cattle Herd Improvement for Increased Productivity Using Embryo Transfer Technology’ was established in 1987. The first buffalo calf from frozen thawed embryo was born in 1991. Till date, 11900 viable embryos have been produced and 720 male calves born using the technology.
Objectives
- To get maximum number of high pedigreed calves from high yielding cows/buffaloes. These can be selected through Herd Registration scheme.
- To accelerate genetic gain / year by selecting the calves on the basis of collaterals’ performance.
- To reduce birth of low potential calves through conventional breeding practices adapted by farmers
- To conserve indigenous germplasm in the form of embryos
Benefits
- Embryo transfer techniques allow top quality female livestock to have a greater influence on the genetic advancement of a herd or flock in much the same way that artificial insemination has allowed greater use of superior sires.
- A high yielding cow/buffalo produces normally 8-10 high yielding calves during life-With ET technology we can get 80-200 calves during its lifetime. Important technology for the breeds which have threats of endangerment.
- The general epidemiological aspects of embryo transfer indicate that the transfer of embryos provides the opportunity to introduce genetic material into populations of livestock while greatly reducing the risk for transmission of infectious diseases.
- Recent developments in the sexing of embryos before transfer and implanting has great potential in the dairy and other livestock industries
Standard Methodology
- Selection of donor and recipient animals
- Synchronization of oestrus & oestrus detection
- Superovulation & Insemination
- Evaluation in laboratory
- Transfer of embryo in recipient cow (Surgical/non-surgical)
- Freezing of embryo for long time storage
- Thawing and transfer as and when requires
ET in the mammalian species, enhanced by multiple ovulation and oestrus synchronization (MOET), allows acceleration of genetic progress through increased selection intensity of females, and freezing of embryos enables low cost transport of genetic material across continents, and also conservation of diploid genomes. MOET may also be used to produce crossbred replacement females whilst only maintaining a small number of the straightbreds. In 1998, worldwide 440,000 ETs have been recorded in cattle, 17,000 in sheep, 1,200 in goats, and 2,500 in horses. About 80 % of the bulls used in AI in the developed world are derived from ET. Despite the potential benefits of ET, its application is largely limited to developed countries. What are the required technical and/or policy elements that will enable developing countries to make use of these technologies on a greater scale ?
ET is also one of the basic technologies for the application of more advanced reproductive biotechnologies such as ovum pick-up (OPU) and in vitro maturation and fertilization (IVM/IVF), sexing of embryos, cloning, and of transgenics. The lack of systems to identify superior animals together with weak technical capacity restricts the use of more advanced technologies like embryo transfer or MAS (marker assisted selection) in developing countries. As per IETS report 2020 1518150 embryo were collected for cattle is 7 percent more than that of 2019. It also stated that more of invitro produced embryos were transferred in comparison to invivo derived embryos. Viewing the world moving towards IVP embryos GOI has launch the Accelerated Breed Improvement Program, through which it hopes to transfer the embryos to farmers. Under the initiative, a target of two lakh embryos has been set up for the next three years. The animal husbandry and fisheries department had sanctioned 31 laboratories to clone cows in 2019, 17 of them are functional as of now. Around 10 of the labs are producing embryos through IVF technology and the rest are still using the earlier Multiple Ovulation and Embryo Transfer (MOET) technology. Right now, the average cost of IVF technology is Rs. 30,000 per calf, but with private players in the market and the government’s added incentive, the average cost would be Rs 20,000.” Although The GOI has taken measures to promote ET in cattle , it is still largely confines to research stations. For the farmers to adopt this technology on their own without the institutional support is not profitable. The cost of preparing the donors, recipient, embryo recovery and transfer to get pregnancy is high. Along with increasing the milk production conservation of indigenous breeds is also a priority of this nation using the potential of AI and ET for cryo-conservation purposes. . Due to changes induced by global warming it is reasonable that the need for indigenous genetic resources will increase.
CATTLE EMBRYO TRANSFER TECHNOLOGY (ETT ) PROCEDURE PDF
Cattle Embryo Transfer Procedure
DR. S. KUMARAN, BENGALURU
References- on request
- Hansen P J. 2020. The incompletely fulfilled promise of embryo transfer in cattle- why aren’t pregnancy rates greater and what can we do about it? J of Anim sci. 98(11): 1- 20 2. Statistics of embryo production in domestic farm animals. 2020. IETs. data retrieval report. 3. Purohit G N. 2019. Reproductive Biotechnologies in Indian cattle. J of Vet Sci and Res. 3(1)1-4 4. Ivanova M., Gradinaska D., Daskalova. 2015. Reproductive biotechnology in animal husbandry- current status and future prospects. 4 th International congress. New perspective and challenges of sustainable livestock production. Serbia. 5. Hadgu A., Fasseha H.2020. Reproductive biotechnology options for improvinglivestock production: A review. Adv. Food. Technol. Nuyr. Sci. 6 (1):13-20. 6. Hernandez and Gifford. 2013. Role of reproductive biotechnologies in enhancing food security and sustainability. Animal Frontiers 3(3): 14-18.
