The ability of analgesic or anti-inflammatory drugs to reduce or eliminate signs of pain can provide evidence, which confirms the presence of pain. The amount and potency of analgesic used can help assess pain intensity.
There is a growing body of information available on the efficacy and pharmacology of analgesics for use in domestic species. Several scientists have investigated the efficacy of drugs by measuring the plasma cortisol response to surgical procedures frequently performed on farmed livestock e.g. rubber ring (Kent et al 1998), surgical and Burdizzo castration (Molony et al 1997; Stafford et al 2002) and dehorning (Sutherland et al 2002a, b).
Local anaesthetic treatment can reduce or eliminate behavioural, physiological and biochemical indicators of pain by blocking transmission of sensory nervous activity from damaged tissues to the brain, thus confirming the peripheral nociceptive basis of the pain (view animation).