Abstract
In the late 1990s, the scientific world was astounded by the news of the successful cloning of a sheep named Dolly (Pence, 2004). This is because animal cloning is popularly understood as the creation of a copy of another animal, much the same way as the capability to create twins but in the laboratory. The significance of this scientific breakthrough is easy to understand as well as the controversies that will inevitably result from simply thinking about the implications of how far human knowledge has advanced. This study will take an overview of animal cloning and then attempt to figure out if the application of this technology can be beneficial to helping animals belonging to the endangered species list as well as the cloning of prized animals such as champion racehorses or cows that produce record-breaking amounts of milk.
Animal Cloning
In order to clearly evaluate animal cloning, there is a need to dispel wrong assumptions and then to provide enough background information regarding this technology to have a basis for analysis regarding the different factors that will ensure success or may prove to be a deterrent to success. Thus, the first thing that we need to look into is the scientific basis for reproducing an animal through cloning. By the way, there are of course many applications of animal cloning aside from using it to increase the number of animals that are considered endangered. For example, farm animals can be cloned to multiply livestock but due to the costly procedure, it does not make sense to spend hundreds of thousands of dollars when simple artificial insemination will do. However, there can be an exception when it comes to cloning prized animals. Consider for instance a cow named Zita, a Holstein that can produce 95 gallons a day of high-quality milk (Pence, 2004). Surely there is an incentive to clone an animal as valuable as this.
It must be pointed out that animal cloning is not much different from the normal way of animal reproduction. Just to clarify we have to remember that animal reproduction requires two types of parent – the male and female. Sexual gametes must be donated by each one in order to produce offspring. Sperm cells must come out from the male animal and egg cells from the female must be ready to receive the sperm cells.
Sperm cells are secreted from the testes of the male animal and these are deposited into the uterus of the female. Once inserted into the female reproductive area the sperm cells have the ability to swim deep into the uterus in order to combine with the egg cell. On the part of the female animal, her ovaries will secrete an egg cell during the sexual act and the egg will travel from the ovary through the fallopian tube and then into the uterus where it gets penetrated by the sperm cell. Once this action occurs the egg is fertilized. Inside the fertilized ovum genetic material from the male sperm cell will combine with the genetic material contained in the female egg cell. This is the reason why the offspring inherits from both the father and the mother. Afterward, the fertilized ovum becomes a complete cell that is ready to multiply and within it, the development of different cells that will grow into different organs of the body and in turn will form the different systems such as the skeletal, circulatory, excretory, and nervous systems. After the gestation period, the offspring will come out from the womb of the mother as it exits via her vagina.
In the case of animal cloning, the same reproductive stages can be seen particularly if we trace the process backward: the birth of the young, gestation period, and multiplication of cells. But the moment we reach the multiplication of cells this is the last stage where the similarity will end and the differences will begin. This is where the major difference between the two processes becomes evident. As you know animal cloning does not require the natural exchange of genetic material between two parents. In the natural method, each parent only provides half of the genetic material required to create offspring. In other words, if you examine the sexual gametes coming from a father and mother each sperm cell and egg cell only contains half of the required number of chromosomes (Genetic Science Learning Center, 2010). This is why there is a need to mate in order to create a complete set of genetic material that is in turn used as a blueprint to create another organism.
In animal cloning, sexual reproduction is not required because the sperm cell is not required to produce a baby. This is why in animal cloning one can reproduce genetically identical offspring each and every time the procedure is successful (Suckow, Weisbroth, & Franklin, 2006). It is like having twins only this time the twins are not brothers or sisters but the offspring is the twin of the parent. One of the established procedures when it comes to animal cloning is a technique called Somatic Cell Nuclear Transfer or SCNT. A somatic cell is any cell in the animal’s body aside from the sexual gametes. In other words, the cell that comprises the ear, the nose, bone is a somatic cell (Cibelli, 2002). The procedure calls for harvesting egg cells from the female. Afterward, a complex set of procedures and sophisticated equipment will remove the genetic material inherent in the said egg cell. When this step is completed, the DNA from a female or male donor is extracted from the donor’s body (Genetic Science Learning Center, 2010) This DNA is inserted into what remains of the altered egg cell. Upon insertion, additional procedures are conducted to induce the egg to behave as if it is a fertilized ovum. If this is successful then the egg cell with the DNA of the donor begins to multiply until it becomes a replica of the donor (Genetic Science Learning Center, 2010). However, the cloned egg will have to be reinserted into the womb of the female or allowed to grow in-vitro throughout the duration of the gestation period of the particular animal that is supposed to be cloned.
There is one major application for animal cloning and this is the use of the technology to successfully reproduce animals that belong to the endangered species list. There are many reasons why a species can be placed in the said list but the moment they are considered endangered there are at least two factors that can hinder them from replenishing their numbers in order to establish a steady population and ensure the survival of the species up to the next generation. The first factor is the dwindling number that can greatly affect the chances of successful mating between male and female. The second factor is the rapid destruction of their natural habitat that even if they successfully produce offspring there is no guarantee that their young will be able to reach sexual maturity.
Criteria
In order for animal cloning technology to succeed as a tool for animal conservation, particularly in the case of endangered species, one has to list down a few criteria for success. The first thing that comes to mind is the requirements needed to produce one offspring through the cloning method. Will it be cost-efficient? Those who will adopt this method will have to make sure that animal cloning will be affordable because there are other means of reproduction that are more practical as compared to the sophisticated method required by animal cloning. One can choose artificial insemination as the natural method all is needed is to bring the female to the male when she is in heat.
The next critical criteria for success is the ease of multiplication. We have to understand that since animal cloning is a man-made operation then everything has to be deliberate and this includes the number of offspring that can be produced each and every time the cloning process is applied. Based on the overview of the cloning process it is easy to surmise that scientists can only produce one cloned egg at a time. By implication, depending on how fast they can alter an egg and then insert the DNA material into it, one can say that only one “fertilized ovum” can be inserted into the womb. There is a need to find out if this can hinder the ease of multiplication.
The third criteria for success is the mortality rate of the offspring born through this procedure and also if the newborn can reach up to sexual maturity in order to sustain the growth of the population. It is therefore not enough to simply succeed in the in-vitro stage such as the insertion of DNA material to the female’s egg cell, the first goal is to have a live birth and the second goal is for the baby to reach maturity. It is only then that one can say that animal cloning is viable in helping those that belong in the endangered species list.
Evaluation
Animal cloning is such a breakthrough technology that it is hard to find serious discussions regarding its practicality in the context of cost-efficiency. Everyone it seems is only interested to know if it works or not. However, when it is time to apply this particular technology to animal breeding then it is important to ask the question of cost-efficiency. It does not require a genius to realize that SCNT will cost a lot of money. One only has to have a basic understanding of the resources and technical expertise needed to complete one cycle of animal cloning. Much can be gleaned from a snapshot of the sophisticated procedure of removing and transferring genetic material as seen below:
While it is true that animal cloning is an expensive procedure one can also say that when seen from the perspective of extinction and highly-prized animals such as racehorses or Holstein cows like Zita, the expenses that will be incurred in reproducing these special types of animals can be easily justified. If bald eagles for instance are about to go extinct many will not mind spending a great deal of money just to save them.
Going to the second criteria which deal with the success rate of animal cloning, we have come to know, based on the review of literature, that animal cloning does not guarantee a high rate of success. There are even those who concluded that the procedure is inefficient if compared to artificial insemination and natural means of reproduction. In the words of two researchers, “But the process is very inefficient, poorly understood and appears highly prone to epigenetic errors resulting in abnormal phenotypes.” (Wells & Laible, 2007). This conclusion must not be ignored. And yet even if there is a high mortality rate the usage of SCNT in animal breeding will still continue if the purpose is not simply to reproduce ordinary farm animals.
Going to the third criteria it has already been pointed out that the procedure is inefficient and that the offspring produced are prone to exhibit genetic errors. This is supposed to be the time when the program director will say that this project is not viable. But again, as one looks at the value of the animals being cloned there is no way that the program can be terminated soon. Scientists and their benefactors will continue to push with the project knowing that the high failure rate must not stop because if they stop then extinction becomes a real threat for some animals and for prized farm animals their usefulness will end in death.
There is one feature of SCNT that will ensure its continuity. It is the discovery that animals born from this procedure can be used in sexual reproduction and reproduce the next generation without defects (Wells & Laible, 2007). Furthermore, it was also discovered that even if the offspring shows signs of defects and are used for sexual reproduction the offspring does not have any evidence of genetic errors. This means that project directors can make the most out of the animals that are reproduced using SCNT.
From the point of view of extinction and the need to perpetuate the productive capability of prized farm animals, there is now no doubt that SCNT as a procedure in animal breeding will go a long way in terms of receiving attention from researchers and financiers. Cost is not a problem because of the value of these animals. Imagine what animal lovers and enthusiasts would pay for to see lion, bear, and eagle species that are near extinction. The goal is not mass production but simply the reproduction of an animal that is genetically the same. This will ensure the survival of the species. For the animals that are valuable in terms of what they can give to the farmers or the businessman, the capability to copy their genetic material is of great importance. As we know it is all in the genes.
References
Cibelli, J. (2002) Principles of cloning. CA: Elsevier Science.
Genetic Science Learning Center (2010) What is Cloning? Learn.Genetics. Web.
Pence, G. (2004) Cloning After Dolly: Who’s Still Afraid? MD: Rowman & Littlefield.
Suckow, M., S. Weisbroth, & C. Franklin. (2006) The Laboratory Rat. MA: Elsevier Academic Press.
Wells, D.N. & G. Laible (2007) Cloning and Transgenesis to Redesign Livestock. In D.
L. Swain (Ed.) Redesigning Animal Agriculture: The Challenge of the 21st Century. MA: Cab International.