<P> On 14 February 2003, Dolly was euthanised because she had a progressive lung disease and severe arthritis . A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived 6.5 years . A post-mortem examination showed she had a form of lung cancer called ovine pulmonary adenocarcinoma, also known as Jaagsiekte, which is a fairly common disease of sheep and is caused by the retrovirus JSRV . Roslin scientists stated that they did not think there was a connection with Dolly being a clone, and that other sheep in the same flock had died of the same disease . Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons . </P> <P> Some in the press speculated that a contributing factor to Dolly's death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned . One basis for this idea was the finding that Dolly's telomeres were short, which is typically a result of the aging process . The Roslin Institute stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging . </P> <P> In 2016 scientists reported no defects in thirteen cloned sheep, including four from the same cell line as Dolly . The first study to review the long - term health outcomes of cloning, the authors found no evidence of late - onset, non-communicable diseases other than some minor examples of osteoarthritis and concluded "We could find no evidence, therefore, of a detrimental long - term effect of cloning by SCNT on the health of aged offspring among our cohort ." </P> <P> After cloning was successfully demonstrated through the production of Dolly, many other large mammals were cloned, including pigs, deer, horses and bulls . The attempt to clone argali (mountain sheep) did not produce viable embryos . The attempt to clone a banteng bull was more successful, as were the attempts to clone mouflon (a form of wild sheep), both resulting in viable offspring . The reprogramming process that cells need to go through during cloning is not perfect and embryos produced by nuclear transfer often show abnormal development . Making cloned mammals was highly inefficient--in 1996 Dolly was the only lamb that survived to adulthood from 277 attempts . By 2014 Chinese scientists were reported to have 70--80% success rates cloning pigs and in 2016, a Korean company, Sooam Biotech, was producing 500 cloned embryos a day . Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans . </P>

Who was the first cloned animal to give birth and how did she get her name