In 1998, Researchers at the Oregon Regional Primate Center cloned rhesus monkeys using the same electrofusion technique that produced Dolly, but cells from several different embryos were used, so the rhesus monkeys that were produced are siblings rather than twins. Notably, the experiment proved the nuclear transfer technology and duplicated Roslin's results. The animals, being primates, are also the most humanlike clones to date.
At the University of Wisconsin, a team led by Tanja Dominko cloned embryos from the skin cells of an adult cow (AgBiotech News & Information 1998). Taken from the cow's ear, the complete skin cells were inserted into enucleated cattle egg cells. An electric pulse was applied to fuse the two cells and make them start dividing into an embryo. These embryos were then implanted into cattle mothers.
In 1997, a company called ABSGlobal announced the birth of Gene, a Holstein bull calf, started from a thirty-day-old fetus (Infigen, Inc.). In their patented process, a cell was removed removed from the fetus and allowed to form a blastocyst of sixteen, thirty-two, or sixty-four cells. Then each of these cells was used to form a separate embryo .
As early as 1992, a company called Granada Biosciences was active in animal cloning from embryonic tissues. Their process entailed separating single cells from a growing calf embryo. Each cell was then injected into an enucleated egg cell and implanted in the womb of a surrogate cow. They experienced a twenty percent rate of success.