Cloning in Farm Animals
How it works
Although cloning may not seem to be a huge practice, it has been done several times in different breeds of animals. Everyone has heard of Dolly the sheep, right? She is the first, and most famous, clone in the world. Cloning is a complex process that lets one exactly copy the genetic, or inherited, traits of an animal(FDA, 2017). The cloning of livestock began in 1996, with Dolly, and has become more prevalent in the years since. There are many reasons a producer may want to clone their livestock, from meat consistency to reproductive efficiency.
Some may say the practice of cloning could change the future of farming.
Cloning, or biological copying, has been successfully done in cattle, swine, sheep, and goats; and that’s just livestock! Scientists have also managed to clone mice, rabbits, rats, cats, mules, horses, and even a dog. However, cloning is a very controversial topic with lots of debate surrounding it, mostly about the welfare of these animals that we are attempting to clone. The first mammal to be cloned was a sheep named Dolly in 1996. According to the Compassion in World Farming Report, in 2010 there were an estimated six thousand livestock clones worldwide. Some parts of the world are already using cloning commercially to produce elite animals for breeding. However, as previously stated, there are some concerns towards the welfare of the clones and the animals used to create the clones. Many cloned embryos do not develop to term and many of the ones that do die during or soon after birth. This is more likely in some breeds than others, such as cattle, but it is still a concern with any cloned animal. Animals used as surrogate mothers are also affected due to the high rates of failure, birthing difficulties, and C-sections. Some cloned fetuses develop much larger than a traditionally bred fetus, which can cause difficulty when giving birth. Due to some of these risks, the cloning of farm animals was banned by the European Parliament in 2015. However, this ban does not include cloning for research purposes or attempting to clone endangered species. The possibility of cloning rare or endangered livestock breeds is one of the reasons people do support cloning. There are more positives to cloning besides just restoring rare breeds. For producers, cloning can introduce positive genetics into a herd in a very short time. Say you have an animal who has always been a great breeder, but it is getting to the point when she can’t be bred anymore. Breeding her offspring and adjusting try to get the same genetics of that original dam could take several years using traditional breeding, but through cloning, you could clone that dam and have the desired genetics in your flock much faster. Another positive to this would be uniformity. If a producer wanted more uniform, higher quality products such as meat, cloning a higher quality animal would be an easier, more effective way to get the uniformity they desire, which will then help their income.
One way cloning is done is by somatic cell nuclear transfer. Cells are collected from a donor animal and cultured in vitro (outside the living organism). An egg cell is collected and matured, the nucleus is removed, and a donor cell is transferred into the egg cell. The donor cell and the egg cell are fused with an electrical pulse and activated by electric or chemical stimulation. After the cell is cultured, it is transferred to a surrogate animal to be carried to term. The resulting animal will be a clone of the donor cell. The cloning of animals is much more efficient than genetically modifying them, and there is a much higher guarantee of getting the genes that you want. Embryo cloning is something that was done before the actual cloning of animals. Embryo cloning is the practice of dividing an embryo into individual blastomeres and electro fusing each one into an enucleated oocyte. This is not a practice that gained a lot of attention like the practice of cloning did. So far, the cloning of animals seems to be the most useful in the food production industry. For example, altered genetics of these clones can be used to create milk with higher levels of proteins or with lower levels of lactose. Higher levels of proteins would be beneficial in cheese yields, and lower levels of lactose would be beneficial to people with lactose sensitivity or allergies. Contrary to some argument, there does not seem to be a difference in food safety between products from normal animals and cloned animals. The European Safety Authority evaluated the safety of food from clones and concluded the following:
“Based on current knowledge, and considering the fact that the primary DNA sequence is unchanged in clones, there is no indication that differences exist in terms of food safety between food products from healthy cattle and pig clones and their progeny, compared with those from healthy conventionally-bred animals. (Farming, 2010) The FDA also evaluated and came to a similar conclusion. In 2001 the FDA requested that food from clones be kept out of the food chain, however this seems to be changing now, and other countries are actively using food from clones in their food chain. There is limited information on immunity and its not clear on if there could be an increased risk to the public if clones are more susceptible to infection. This is something that, with the advancement and growing popularity of cloning animals, should continue to be studied. Clones are primarily intended to be used as breeding animals and not as human food, however offspring of clones are valuable candidates to enter the food chain (Louis-Marie Houdebine, 2008). According to the people who wrote the article “Animal cloning for food: epigenetics, health, welfare and food safety aspects, cattle and pigs will more than likely be the first species where clones are used for food.
Dolly the sheep was the first mammal to be cloned from an adult cell. She was born in 1996 in Scotland as part of some experiments at The Roslin Institute. Dolly was “made from a cell that was taken from the udder of her biological mother, which was then inserted into a sheep ovum and manipulated to create an embryo (Jesper Lassen, 2006). After that, the embryo was placed into a foster mother who carried Dolly until birth. Dolly was international news, and everyone knew about her life and, eventually, her death. However, most people are not fascinated by her life, but they think of it with fear and anxiety. Her life did, and continues to, spark debates on the ethics of scientists cloning animals. As talked about before, many people don’t agree with cloning due to the ethics of it and the fact that some cloned animals suffer health issues and do not live full lives. Scientists used to mainly be worried about what it was possible for them to do, but with all the ethics arguments circulating now, the bigger question they must consider is what is acceptable for them to do. Cloning is not the only use of biotechnology in agriculture, but it seems to be the one most people are concerned with. In 1952 embryo cloning was used in frogs, and this led to more and more advancements until Dolly came along. Dolly made history; her life was something that opened doors for scientists and has led to so many breakthroughs. Scientists wouldn’t be where they are today if it wasn’t for what Dolly started. She died in 2003 from lung disease and arthritis but before this she gave birth to six lambs. She was proof that some clones can live to a more advanced age and even give birth; they don’t have severe reproductive issues like many people believe. Dolly is now on display at the National Museum of Scotland for everyone to see and remember the amazing life she led.
The cloning of farm animals, though a very controversial topic, is a practice that is gaining popularity around the world and could be useful to producers in so many ways. Cloning can be used to preserve the genetics of old, diseased, or dead animals, re-create animals without reproductive issues, eliminate diseases, create herd uniformity, and so many other things. With time, cloning will be able to be used for more and more things. Other countries are already using clones for meat, and eventually if the FDA approves it, the United States could too. Cloning is a complex process that lets one exactly copy the genetic, or inherited, traits of an animal (FDA, 2017) and it’s a practice that could change the future of farming as we know it.