Embryo transfer technique

The world is broadening the margins of bio-technology, reaching the top achievements in it with experiments like cloning, test-tube babies and such things. We, Sri Lankans also have proved that we also have the ability in practicing the developed bio-technology.

 Dr. Basil Alexander

"We have enough human resource that has the ability to handle the developed technology and can create high standard offspring", says Dr. Basil Alexander, senior lecturer in the Department of Health and Animal Production at the University of Peradeniya. A consultant embryologist is a leading figure who engages in biotechnology, practicing the embryo transfer in animals.

The embryo transplant is a process by which an embryo is collected from one female (donor) and transfered to another female (recipient) to complete the gestation period. This can also be considered as a type of artificial insemination, but what differentiates here is, it multiplies the genetic characters of the female, while in artificial insemination it is of the male. The reproduction potential of a female is enormous as her ovaries contain about 150,000 'eggs' or ova at the time of birth. Each egg has the potential of developing to an embryo and to an offspring. But in natural reproduction she does not make use of a large fraction of her reproductive potential as she uses only a fraction of those eggs. For instance a cow will give birth to an average of 8-10 calves for her life time. But in the embryo transfer technique, it can utilize the maximum reproductive potential of a genetically superior female animal that results in hundreds of superior offspring on the ground. Thus a lot of countries engage in this technique to increase farm production mostly using cows, horses, pigs, goats and other farm animals.

An embryo seen through a microscope

In Sri Lanka this technology is being practicd since 2007 by a research team under the assistance of Dr. Alexander who returned to Sri Lanka after specializing this technology for his PhD. They succeeded in the first experiment level embryo transfer that gave birth to 'Apeksha', the cow and in 2008 an experiment resulted in 'Peradeni Kumari', the female goat kid. For two years now 70 calves have been calved. The embryo transfer technique has some steps as selecting a genetically superior female which has a high milk producing capacity, high meat producing capacity and high resistance for diseases; super ovulation of the donor which means use of reproductive hormone (follicular stimulating hormone, FSH) on the embryo donor animal for 2-3 days in order to ovulate many numbers of eggs (multiple ovulation) from her ovaries; the insemination of the female following super ovulation which make the eggs fertilize in uterus, then the embryos develop; they are collected by embryo flushing technique and evaluated to transfer the excellent embryos into the uterus of the recipient animals; embryo transfer; the particular animals are examined for pregnancy using ultrasound scanning and then well cared.

This whole process will cost about Rs.40, 000 for a single animal. Anyhow this process gains more validity as the calves get accustomed to the new atmosphere as they are getting protection from diseases from the colostrums of the recipient mother's milk which has antibodies. This method is conducted in both surgical-used in animals like goats- and non-surgical method, mainly used in animals like cows.

                                                                           The first cloned female goat kid Peradeni Kumari with her mum  

The embryos which are transplanted in the Sri Lankan cows were imported from Australia, which are with high pedigree cattle like Jersey, Friesian and AFS (Australian Friesian Sahiwal). These embryos are frozen by an embryo freezer and then preserved in liquid nitrogen which is of -106 degrees and that can be kept for a long time even like 200 years.

Anyhow the success of this technique is of 50 percent in Sri Lanka which is ample while in other countries it is of 80 percent. We fail for some extent in this, mainly because some imported embryos become infertile when it is transplanted and also the short comings in special nutritious food for the embryo recipients. If we have elite cows that give embryos which can be transplanted with a short period this process will be more successful.

The cloned cows

So Dr. Alexander is planning to create an "elite herd" which results in multiple farms and then multiple farms result in commercial farms. The specialty of this technology is it can be mainly used in conserving endangered animals. So now this is practiced in zoological gardens all over the world.

The laboratory which is used in these experiments was established in the University of Peradeniya in 2006. The financial assistance was given from the Council for Agricultural Research Policy (CARP) and the equipment was donated from the University of Guelph, Ontario, Canada. The laboratory is now conducting researches in indigenous animal conservation using their semen, somatic cells and germ plasm cryobanking; and wild buffalo conservation using reproductive biotechnologies and investigation of wild buffalo and indigenous buffalo genetic diversity using DNA molecular techniques.

At the same time, plans are underway to breed generically superior horses in Sri Lanka through Artificial Insemination using horse semen imported from USA. The laboratory also provides consultancy services to cattle embryo transfer project in the National Livestock Development Board in Sri Lanka and also provides services (field infertility clinics) for cattle and goat farmers to overcome reproductive problems among the livestock breeds. The team is planning to clone animals using somatic cell nuclear transfer technology.

All these researches are conducted with the assistance of Council for Agricultural Research Policy (CARP), Ministry of Livestock and Development, Department of Animal Production and Health and Dr. Chandravansa Pathiraja, Chairman of National Livestock Development Board.

.