Some of these can be mixed in with wood shavings so that they have to forage for their food - a favourite activity. See also our pages on animal welfare and regulation . A lot of scientific effort has been devoted to developing new, non-animal techniques which can be used in experiments instead of animals. There have been some notable successes, but overall, progress has been disappointingly slow. The LAL test can now be used to test for pyrogens.
Bacteria often shed little bits of their outer covering.
If these substances, known as pyrogens, get into the bloodstream, they raise the body temperature. Even very tiny levels of pyrogens cause a dangerous temperature rise, so any liquid going to be injected or fed into a patient's blood stream has to be tested for pyrogen contamination. Previously this was done by injecting the liquid into a rabbit and monitoring the animal's body temperature. The new LAL test uses white blood cells taken from the horseshoe crab which can detect the pyrogens in a test-tube. Insulin is a lifeline for millions of diabetics, but it is essential they give themselves the correct dose - either too high or too low a dose can be harmful.