“Integumentary (Outer Surface) Sensitivity,” Commercial Chicken Meat and Egg Production, 5th edition, p. 80: “The
integument of the chicken (skin and accessory structures, e.g., the beak) contain many sensory receptors of several types allowing perception of
touch (both moving stimuli and pressure stimuli), cold, heat, and noxious (painful or unpleasant) stimulation. The beak has concentrations of touch
receptors forming specialized beak tip organs which give the bird sensitivity for manipulation and assessment of objects.”
Poultry Sentience and Intelligence
From an Interview with Dr. Ian Duncan, Professor of Poultry Ethology
University of Guelph
Q: Can chickens and turkeys feel pain?
A: Absolutely. It is indisputable that poultry are capable of feeling pain. All poultry species are sentient vertebrates and
all the available evidence shows that they have a very similar range of feelings as mammalian species. Poultry can suffer by
feeling pain, fear and stress.
Q: Chickens and turkeys are widely regarded to be of inferior intelligence, so-called "dumb animals." Is this an accurate
assessment of their intelligence?
A: Not at all. These animals are poorly understood. Turkeys, for example, do not always do what a turkey grower wants them to,
and therefore they're classified as dumb animals, whereas in fact turkeys possess marked intelligence. This is revealed by such
behavioral indices as their complex social relationships, and their many different methods of communicating with each other,
both visual and vocal. Chickens, as well, are far more intelligent than generally regarded, and possess underestimated
cognitive complexity. From The State of Poultry Welfare in Canada, 1996. An interview with Dr. Ian Duncan.
Pain and Suffering in Birds
Karen Davis, PhD, President, United Poultry Concerns
Chickens and turkeys - birds - experience pain, panic, fear and distress the same as other animals including humans. Pain
receptors, thermo-receptors, and physical-impact receptors responsive to noxious (tissue damaging) stimuli have been identified
in birds and characterized in chickens. Like mammals subjected to painful stimuli, chickens show a rapid increase in heart rate
and blood pressure, and behavioral changes consistent with those found in mammals indicating pain perception - efforts to
escape, distress cries, guarding of wounded body parts, and the passive immobility that develops in birds and other animals
subjected to traumatic events that are aversive and that continue regardless of attempts by the victim to reduce or eliminate
them (Gentle 1992).
Michael Gentle states in “Pain in Birds” that comparing the physiological responses of the nociceptors (pain
receptors) found in chickens with those found in mammals, including humans, “it is clear that in terms of discharge
patterns and receptive field size, they are very similar to those found in a variety of mammalian species.” Birds, like
mammals, he explains, have “a well-developed sensory system to monitor very precisely external noxious or potentially
noxious stimuli.” He concludes that the “close similarity between birds and mammals in their physiological and
behavioral responses to painful stimuli would argue for a comparable sensory and emotional experience” (Gentle 1992,
Birds are Intelligent Beings
In addition to comparable sensory and emotional experiences, birds have cognitive abilities “equivalent to those of
mammals, even primates” (Rogers 1995, 217). This conclusion is shared by the Avian Brain Nomenclature Consortium, an
international group of scientists. In a paper published in Nature Neuroscience Reviews in 2005, the Consortium
presented the overwhelming evidence showing that a bird’s brain is a highly complex organ of which fully 75 percent
“is an intricately wired mass that processes information in much the same way as the vaunted human cerebral
cortex.” In light of this evidence, the Consortium is calling upon scientists around the world to adopt a new language to
describe the various parts of the bird’s brain in recognition of what is now known about avian intelligence upsetting the
“old system [that] stunted scientists’ imaginations when it came to appreciating birds’ brain power”
(Weiss 2005). As for chickens in particular, scientists observe that “chickens evolved an impressive level of
intelligence to help improve their survival” (Viegas).
The question is what will we do with this knowledge?
[The] Avian Brain Nomenclature Consortium. 2005. Avian Brains and a New Understanding of Vertebrate Brain Evolution.Nature Neuroscience Reviews 6 (February): 151-167. www.Avianbrain.org.
Gentle, Michael J. 1992. Pain in Birds. Animal Welfare 1: 235-247. Universities Federation for Animal Welfare.
Rogers, Lesley J. 1995. The Development of Brain and Behaviour in the Chicken. Oxon, UK: CAB International.
Viegas, Jennifer. 2005. Study: Chickens Think About Future. Discovery News July 14.
Weiss, Rick. 2005. Bird Brains Get Some New Names, And New Respect. The Washington Post 1 February, A10. www.upc-online.org/alerts/20105post.htm.
From Karen Davis, PhD,
Prisoned Chickens, Poisoned Eggs: An Inside Look at the Modern Poultry Industry. Summertown, TN: Book Publishing Company, 2009. pp. 158-159.