It’s a simple, nearly instantaneous test that goes by the name of the LAL, or Limulus amebocyte lysate, test (after the species name of the crab, Limulus polyphemus). The LAL test replaced the rather horrifying prospect of possibly contaminated substances being tested on “large colonies of rabbits.” Pharma companies didn’t like the rabbit process, either, because it was slow and expensive.

From https://www.theatlantic.com/technology/archive/2014/02/the-blood-harvest/284078/ (emphasis mine).