Cattle produces one calf every two years. With conventional breeding , it would take several decades to breed livestock with improved genetic traits. This long period can be shortened through biotechnology, specifically, the multiple ovulation and embryo transfer (MOET) technique. This makes the production of animals with superior traits easier and to multiply these animals more rapidly.
Multiple ovulation, also known as superovulation is the production of a large number of ova by a dam of superior genetic traits. Through this technique, more embryos are generated, therefore, more calves are produced form one superior cow. Embryo transfer is the removal of the fertilized eggs and embryos from the donor cow then transferred to the uterus of dams undergoing the estrus cycle for gestation. Gestation is the process of carrying the embryo in the womb for growth and development. The MOET technique is used to conserve superior breeding stock or to improve the rate of genetic gain of selected herds. This process is effective for livestock with low prolificacy such as cattle.
A group of scientists from the Institute of Animal science, University of the Philippine Los Banos tried the technique in collaboration with the Philippine Carabao Center (PCC) and ANSA Genetics, Incorporated. They wanted to determine the number of embryo produced, quality and stage at the time of recovery, and cost of production using the MOET technique under Philippine condition.Normally, a dam or a female cow produces only one ovum in an estrus cycle but by injecting it with a hormone or superovulatory drug, multiple ovulations occur or more ova are produced. Using the MOET technique, the donor cows were injected with the superovulatory hormones during ovulation. They were artificially inseminated with semen from a bull. Six to seven days after AI, the embryos were taken out non-surgically by using a catheter, a thin, flexible tube inserted into the uterus. Four to seven embryos were collected from each treated cow. One embryo was then implanted into each recipient cow undergoing the estrus cycle.
The researchers found that the cost of producing one embryo was lowest with a Holstein sire breed and an AFS dam breed and using p-FSH (porcine stimulating hormone).
Genetically superior animals are still the basis of livestock breeding. With biotechnology, the best female animals are being used as a source of genetic materials rather than a source of direct offspring. And MOET means that a single cow may be used to breed many cows each year.
Source: BAR TODAY, January- March issue 2002 by Rita T. Dela Cruz and Virginia A. Duldulao
“local success rate and costs of multiple ovulation and embryo recovery in cattle” Orville L. Bondoc, IAS-CA UPLB