Under the Australian Code of Practice, animals must not be allowed to experience pain and distress of a degree and kind which would normally warrant alleviation, unless there are most exceptional circumstances. Such circumstances are most likely to occur with long-term studies of pain or inflammatory mechanisms, where the agents which would be used to alleviate pain or distress will directly interfere with the processes under investigation. In these cases, alternate approaches and the strategic use of analgesics during the development of the pathological processes under study should be considered.

Strategies to relieve pain are directed towards

• the pharmacological elimination or control of pain by the use of anaesthetics or analgesics and
• the alleviation of the impact of the experience by a variety of strategies including the modification of procedures or research protocols.

Remember, careful monitoring of your animals (as discussed in Problem 1) is essential to effectively identify and relieve pain or distress.

In the case of distress not associated with pain, although strategies may involve the use of drugs to alleviate anxiety, in most cases a non-pharmacological approach is preferable. Most often, in the laboratory setting, this can be achieved through a review and modification of animal husbandry and management practices.

Anaesthesia - A significant proportion of animal studies are conducted under anaesthesia. The most appropriate method, not only for the species (Refinement, Replacement) but also for the research objective (Reduction), should be selected.

Analgesia -The use of analgesics in laboratory animals can be approached from the same premise ie. choice of the most appropriate agent for the species and the circumstances.

Details to be considered in the choice of the most appropriate agent for the species and the experimental design can be found in:

Flecknell PA (1996) Laboratory Animal Anaesthesia - A practical introduction for research workers and technicians. 2nd Ed. Academic Press, London UK. ISBN 0-12-260361-3

Kohn, DF, Wixson, S., White, WJ., Benson, GJ (1966) Anaesthesia and Analgesia in Laboratory Animals Academic Press, Orlando, Florida. ISBN

Non-pharmacological methods - In people, the experience of pain and distress is modulated by emotional and cognitive influences and the particular circumstances under which that experience occurs. Anxiety also plays a major role. Such factors can be used to modulate the experience of pain in humans by non-pharmacological means and there is evidence that they have a similar potential in animals.