Flowers and pets
Embryo transfer technique
Madubashini RATHNAYKA
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 thorugh 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.
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 cloned cows. Pix Dr. Basil Alexander |
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 Pathirana, Chairman of National Livestock Development
Board. |