All animals must be properly housed, fed and cared for. Pain and distress must be minimised and the UK controls state that there must be a vet on call at all times. These controls also make sure that any animal suffering severe pain which cannot be alleviated is put down immediately. The three Rs are the guiding principles in animal research. Reduction means that numbers of animals are minimised.
Replacement means that non-animal alternatives are used whenever possible.
Refinement means that animals are looked after properly and any pain or distress minimised. Fish, amphibians, birds, rabbits and larger mammals such as pigs and sheep are also used. It is estimated that world wide up to 50 million animals are used in research every year. Most animal research involves little more than injections, taking small blood samples, feeding or breeding studies. If animals undergo surgery, they get anaesthetics just like human patients.