Pain in non human animal

Pain in Non-Human Animal to Humans

Whether or not nonhuman animals can experience pain happens to be a rather interesting topic in the realms of neurology, philosophy, medicine, as well as animal biology and behavioral ecology. However, it would be prudent to note that as Ferdowsian and Merskin indicate, “unlike human suffering, the wide range of acute, recurrent, and chronic stressors and trauma on nonhuman animals is rarely evaluated” (448). In this text, I’ll concern myself with pain in birds. Special references will be made to poultry.

From the onset, it should be noted that most studies in this realm appear to be mostly focused on the evidence of pain in birds from a physiological and behavioral perspective. Parallels could, however, be drawn between pain in birds and pain in mammals. This is more so the case in relation to both having a sensory system that is well developed and has the capability to keep track of noxious stimuli. Indeed, according to Machin, “pain in birds, as with mammalian species, is associated with peripheral detection and transmission of noxious stimuli, and the central processing of noxious information into perceived pain” (237). As Gentle observes, many chicken body parts have been shown to have nociceptors – i.e. following the identification as well as physiological characterization of the said receptors (252). In essence, noxious stimulation is responded to by the said receptors. Parts of the body that have been shown to have these receptors are inclusive of, but they are not limited to; scaly skin, joint capsule, nose, mouth, the beak, etc. (Gentle 252). When these nociceptors are stimulated, they trigger changes (behavioral and cardiovascular) that are similar to those witnessed in mammals, and are associated with the perception of pain (Gentle 252).

Various experiments (behavioral and physiological) have in the past been conducted in an effort to better understand the manifestation of pain in birds. In one such study, it was indicated that in chicks, beak trimming is linked to acute pain (Gentle 253). Further, according to the author, there is also evidence of the possibility of chronic pain in hens following the breakage of bones. Indeed, in the words Gentle, poultry pain studies and inquiries have, in addition to highlighting chronic and acute pain circumstances, “also provided information on qualitative differences in the pain experienced as well as identifying a cognitive component providing evidence of conscious pain perception” (253).

Changes in normal behavior could, according to Malik and Valentine, be associated with pain in birds (11). For this reason, indicators of pain among birds could be inclusive of temperament changes (restlessness, antisocial behavior, etc.), locomotion changes (issues with mobility, inability to perch, etc.), posture or demeanor changes, etc. (Malik and Valentine 14). Guarding behavior has also been observed, with Malik and Valentine pointing out that an injured bird is likely to guard the area of the body in pain (14).