Organ replacement in animals
Limb replacement (prosthesis) in animals is a well developed science and becoming more common. Organ replacement is rarer and much more difficult. The first pacemaker surgery on a dog was performed in 1968. About 300 pacemakers are implanted in dogs each year. Successful kidney transplants in cats have been around since the mid-1980s. Canine programs have been less successful due to the problems of immunosuppression. The way donor animals are treated remains a source of concern.
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