Ovine pulmonary adenocarcinoma as an animal model for human lung cancer, because OPA is histologically similar to human adenocarcinoma in situ of the lung. Dolly the sheep, the first mammal successfully cloned from an adult somatic cell, was euthanized after it was confirmed that she had OPA. Ovine pulmonary adenocarcinoma Ovine pulmonary adenocarcinoma (OPA), also known as ovine pulmonary adenomatosis, or jaagsiekte, is a chronic and contagious disease of the lungs of sheep and goats. OPA is caused by a retrovirus called jaagsiekte sheep retrovirus (JSRV). The disease has a long incubation period, and therefore signs usually occur in adult animals (over 2
Alternatives to animal testing Alternatives to animal testing Alternatives to animal testing are the development and implementation of test methods that avoid the use of live animals. There is widespread agreement that a reduction in the number of animals used and the refinement of testing to reduce suffering should be important goals for the industries involved. Two major alternatives to "in vivo" animal testing are "in vitro" cell culture techniques and "in silico" computer simulation. However, some claim they are not true alternatives because simulations use data from prior animal experiments and cell cultures often require animal derived products, such as serum or cells.