The use of animals in experimental research has soared at US laboratories, according to People for the Ethical Treatment of Animals (PETA), and taxpayer-funded scientists are the culprits.

The 25 largest recipients of government funding increased animal experimentation 73 percent in 15 years, despite growing public opposition to the practice and mounting evidence that animal studies often do not faithfully translate to people, they write.

They also say the data contradict government claims of reduced animal use and are at odds with government policies designed to curb and replace the use of animals in experiments. 

How can that be? The US leads the world in science and so is also the world's largest user of animals in experiments. Government data do show declines in the use of cats, dogs, primates, rabbits, hamsters and other larger mammals, but those have been replaced with mice, rats and birds bred for experimentation, along with cold-blooded animals.

PETA used Freedom of Information requests to obtain previously unpublished data collected by the US National Institutes of Health (NIH) on the use of all vertebrate species at the top 25 institutions in receipt of its grants. The analysis showed that use of animals in laboratory research at these facilities rose by just under 73 percent between 1997 and 2012. This was largely driven by increases in the use of mice while the use of other species remained mostly unchanged. Unregulated species made up almost all (98.8 %) of the animals used at these labs. 

PETA says this is the first time data on the prevalence and trends in use of these species in the US has been published, and the pattern mirrors international reports of increases in the use of mice for genetic modification. They say the figures highlight a need for greater efforts to curb the use of animals in scientific research and more transparency in reporting on whether these are succeeding. 

A simplistic view of science, to be sure, and it will only heighten the tension between scientists and animal rights advocates. Scientists feel like they have already cut back on animal testing and eliminating mice would just mean going from a dish to human experimentation, which would be incredibly dangerous.

Citation: Justin Goodman, Alka Chandna, Katherine Roe, 'Trends in animal use at US research facilities', J Med Ethics doi:10.1136/medethics-2014-102404