Animal Cloning

The use of reproductive biotechnology may be the most sophisticated research and development (R&D) work that the Philippines is into now in the agriculture sector.
The development of somatic cell nuclear transfer (SCNT), popularly known as cloning, in carabao has been pursued by the Philippine Carabao Center (PCC) since mid-2000.
Its purpose may not really be for the immediate reproduction of superior carabao breeds that can right away efface a $500 million dairy yearly import.
But who knows? It can just turn out to be a field the country may have a global niche in since no carabao has yet been cloned elsewhere. None yet, even in China where one cloned carabao was reported to have been born, but never survived, according to PCC experts.
The famous Dolly, a sheep, was the first successful cloned mammal as announced by the journal Nature in February 1997. After this, other mammals have been cloned including the mouse, cattle, goat, pig, deer, rabbit, cat, mule, and horse.
Cloning, an act of producing a copy or identical copies of a biological material, may refer to any of these three types: cloning of a gene or segments of deoxyribonucleic acid (DNA); reproductive cloning or copying of whole animals like Dolly; and therapeutic cloning.
The last is about the production of embryonic stem cells (ESC) that can create tissues that can replace injured or diseased tissues.
In cloning, somatic cell from an animal is taken, in the case of the cloning of the carabao here, a cell from an animal’s ear skin. The DNA from this donor animal’s cell, using its nucleus, is then transferred into an egg cell or oocyte whose nucleus has been removed so that the egg cell will obtain the DNA from the donor animal.
The egg then develops into an embryo and is later implanted in a womb of a surrogate mother.
After a few attempts on carabao cloning, scientists at PCC are looking into ways of solving abortion of the fetus after around three months in the womb (a fetus lasts 11 months in the womb before birth).
They’re looking at epigenetic factors that cause abortion. They may try to resolve abortion by making sure that the actual stage of the DNA material in the egg of the donor animal is synchronized with the reproductive cycle stage of the surrogate mother.
The idea of cloning is to multiply the effort to propagate superior animal breeds at an accelerated time.
Cloning is not really an old technology as some may think. Animal cloning itself using SCNT has been here for around 30 years. But cloning in plants has been here for decades with grafted fruits like bananas. Or else, through conventional breeding from seed, banana breeding can take 30 years.
Cloning may be the most interesting of all reproductive bio-techniques, and even controversial with moral implications of cloning human.
But scientists at PCC employ other technologies in reproduction whose uses have been more extensive and commercially applicable.
Ovum pick-up (OPU)/ in vitro maturation (IVM)/in vitro-fertilization (IVF). To breed animals with high milk production, researchers need sperm and egg cells from both superior animals. They usually get the egg cells of slaughtered carabaos in India. But this does not guarantee obtaining the best breed, thus the need to obtain it from a known live superior animal through OPU. An OPU enables researchers to get immature egg cells from a superior animal through aspiration with the aid of ultrasound.
But the oocytes have to mature within 24 hours through IVM which is done in the laboratory as the in vitro name implies. The IVF process follows where egg and sperm cells are fertilized and subsequently frozen for future transfer to the womb of a surrogate dam.
Embryo transfer (ET). With fertilization done in the laboratory, the embryo is now transferred inside, or in vivo, of a womb of a surrogate dam. Under this technique, PCC already has 12 to 15 successful birth through embryo transfer according to Dr. Annabelle S. Sarabia of PCC. But these successful cases are mainly used for technology development, rather than for immediate dairying.
Cryopreservation. This is the preservation under below zero degree Celsius freezing temperature of tissues, cells, embryo, semen of animals not only of carabao but also of cattle, goat, sheep, and other livestock animals (since PCC was appointed by Agriculture Secretary Arthur C. Yap as animal biotechnology center in the Philippines). The cryo bank at PCC-Nueva Ecija headquarters now has 76,249 entries including purebreds and crossbreds of carabao and cattle and riverine buffaloes. Of this total entries, 2,168 are native species and 881 of the carabaos already have Expected Breeding Values (EBV) primarily indicating milk production record.
It will enable scientists to draw out these samples for future reproduction specially when they are later found or predicted to have desirable traits.
It will boost the development of the country’s animal recording system even if this system is just new to the Philippines while other countries like the United States have long maintained their cattle herd books for centuries.
Futuristic Gene pharming/transgenesis/xenotransplantation. While R&D on these technologies are not yet present in the Philippines, PCC looks forward to future R&D on these. Gene pharming aims to produce pharmaceutical products (vaccine, medicine) through the production of recombinant pharmaceutical proteins in the mammary gland of animals that have been genetically engineered.
That goes with the use of genetic engineering (GE) or transgenesis which enables transfer of desirable trait-carrying DNA between different breed or species. The use of GE on pigs has once been employed by scientists to determine if a certain gene has the capability to increase cholesterol level in human, whether or not he is a heavy-eater of cholesterol-carrying foods.
Moreover, xenotransplantation has been an object of R&D for scientists abroad for its potential in the use of animal organs, such as a pig’s heart, to be transplanted to human which will make organs’ supply limitless. end---------