Scientists' salaries and professional status are often tied to grants, and a critical element of success in grant applications is proof of prior experience and expertise. Researchers trained in animal research techniques find it difficult or inconvenient to adopt new methods, such as tissue cultures. The control, however, is illusory. Any animal model differs in myriad ways from human physiology and pathology. Such variables can have system-wide effects, skew experimental results, and undermine extrapolation of findings to humans.
Vivisection is lucrative .
Its traditionally respected place in modern medicine results in secure financial support, which is often an integral component of a university's budget. Many medical centers receive tens of millions of dollars annually in direct grants for animal research, and tens of millions more for overhead costs that are supposedly related to that research. Since these medical centers depend on this overhead for much of their administrative costs, construction, and building maintenance, they perpetuate vivisection by praising it in the media and to legislators. Animal researchers' ethical defense of the practice has been superficial and self-serving. The general public, which cares about animal welfare, has been led to believe that animals rarely suffer in laboratories.