In a clinical trial from 1969 to 1972, Sir Graham Collingwood Liggins and Ross Howie showed that if doctors treat pregnant women with corticosteroids before those women deliver prematurely, then those women's infants have fewer cases of respiratory distress syndrome than do similarly premature infants of women not treated with corticosteroids. Prior to the study, premature infants born before 32 weeks of gestation often died of respiratory distress syndrome, or the inability to inflate immature lungs. Liggins and Howie, then both at the University of Auckland in Auckland, New Zealand, published their results in A Controlled Trial of Antepartum Glucorticoid Treatment for Prevention of the Respiratory Distress Syndrome in Premature Infants in 1972. The study built on experiments Liggins had earlier conducted with sheep. Liggins' corticosteroid experiments changed the way doctors treated pregnant women experiencing preterm labors, and they improved the life expectancy of prematurely born infants.

Keith Henry Stockman Campbell studied embryo growth and cell differentiation during the twentieth and twenty-first centuries in the UK. In 1995, Campbell and his scientific team used cells grown and differentiated in a laboratory to clone sheep for the first time. They named these two sheep Megan and Morag. Campbell and his team also cloned a sheep from adult cells in 1996, which they named Dolly. Dolly was the first mammal cloned from specialized adult (somatic) cells with the technique of somatic cell nuclear transfer (SCNT). Campbell helped develop cloning techniques that used a common form of connective tissue cells (fibroblasts). Besides working at the Roslin Institute, in Edinburgh, Scotland, for most of his career, Campbell also taught at the University of Nottingham in Nottingham, England.

In 1984 Sabine Meinecke-Tillmann and Burkhard Meinecke published their article "Experimental Chimeras - Removal of Reproductive Barrier Between Sheep and Goat" in Nature. Their study conquered the reproductive barrier between sheep and goats through embryo manipulation. Their article appeared in Nature on the same day that a similar experiment, conducted by Carole Fehilly, Steen Willadsen, and Elizabeth Tucker was published regarding reproductive barriers between sheep and goats. In previous experiments involving the transplantation of sheep embryos into recipient goats or vice versa, the embryos did not survive past the initial weeks of pregnancy. Hybridization experiments had also failed between the species. Although scientists were unsure of the reasons that hybrid eggs from donor sheep did not survive, they attributed the death of the hybrid eggs from donor goats to immunological responses. Meinecke-Tillmann and Meinecke created interspecific chimeric embryos in order to address the reproductive obstacles between the species. These embryos were transferred to sheep, and a sheep successfully brought a goat kid to term.

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