Dolly the cloned sheep was born more than two decades ago on July 5. As the first mammal cloned from an adult cell, she remains one of the most famous cloned creatures today.

Since then, cloning has progressed greatly, but the process occupies anethical gray area. Animal cloning may have the potential tobring back extinct species, but according to a Gallup poll conducted earlier this year, most Americans do not morally support cloning. When considering the future of cloning, here are some animal rights concerns to keep in mind.

Cloned animals often live shorter and sicklierlives than their naturally produced counterparts. For instance, the New Zealand-based AgResearch shut its doors in 2011 because too many animals died in its studies.Only 10 percent of the cloned animals even survived research trials, according to the company. The National Human Genome Research Instituteadds that cloned sheep can bebigger at birth and have defective livers, brains and hearts. They also tend to die younger.

In 2013, UK pet owners got the opportunity to clone beloved dogs after they died. However, the process set some people up for disappointment when their new pet isntthe same as itsgenetic counterpart. Care2s Steve Williams explainsthat these expectations could lead owners to get rid of their dogs, whether byreturning them, taking them to an animal shelter or opting for euthanasia.

As the Humane Society of the United States notes, pet cloning doesnt get the same federal scrutiny that animal testing facilities do in the United States. The Department of Agriculture doesnt even require those cloning cats and dogs to follow the bare-bones rules of the Animal Welfare Act.

Animals involved in cloning are often exposed to painful and invasive research practices and kept in sterile, uncomfortable conditions. As the Humane Society says, The egg donors and/or surrogate mothers are subjected to painful hormone treatments to manipulate their reproductive cycles. These animals are also subjected to invasive surgery to harvest eggs or implant embryos, and the surrogate mothers endure an additional surgery to deliver the baby.

From a more abstract line of thought, some argue cloning devalues animals because it treats them as commodities. A paper from the University of Pennsylvanias Center for Bioethicsstates:

While cloning opponents admit that animals are already considered property and products, they argue that cloning takes this objectification to new levels. Life for animals in agriculture, research, and the pharmaceutical industry is already bad enough, its argued; cloning will desensitize us further from the suffering of these entities, placing them even more firmly in the thing category.

While cloning has its place, these ethical problems must be addressed.

Photo Credit: Wikimedia Commons

Disclaimer: The views expressed above are solely those of the author and may not reflect those of Care2, Inc., its employees or advertisers.

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5 Reasons to Think Twice About Animal Cloning - Care2.com