By Cecile Ashen-Young

The first problem associated with measuring an animal’s feelings is to decide or agree upon or take a stance about whether animals have feelings (Fraser, 2009).  Animal welfare science had reached a stage where scientists had to confront the “hard problem” of whether animals are sentient, in other words, whether they experience emotions and feelings.  Dawkins (2006) describes sentience as the ability to experience consciousness, in particular “the basic experiences of seeing, hearing, feeling pain etc”. And in fact, research over the past decade does support the sentience of animals. However, the problem remains that feelings are not directly observable, so how can we operationally define them?    


Until recently, animal welfare science has focused primarily on identifying and assessing negative states in animals including fear, pain, separation distress, avoidance learning, stereotypic behaviour and, more recently, boredom.  These assessments are done using a number of methods: choice tests, preference and motivation tests, and observations of abnormal behaviour possibly resulting from severely deprived or inappropriate environments.  Scientists are now including the study and assessment of positive affective states by ‘asking’ what animals like (the affective consequence or positive feelings associated with reward) and want (a mental state associated with appetitive motivation). 

There are different methods and different approaches to assessing and measuring an animal’s positive affective state, i.e., if they ‘like’ or ‘want’ something.  The first method is the use of physiological markers via the use of imaging techniques (EEG, PET or MRI) to test whether the pleasure centers respond.  The second method is to test how positive affective states affect cognitive processes by measuring how an animal processes visual, olfactory and auditory cues.  The third method involves measuring behavioural markers using direct manifestations of positive affective states such as facial expressions and vocalizations.  Indirect manifestations may also be measured through, for example, an increase in play behaviour as a result of a positive affective state (Dawkins, 2006).      

One of the approaches used to understand and facilitate assessment of the positive affective states of animals is to sort their positive feelings according to classifications of analogous feelings in humans.  Whereas human happiness may be divided into “the pleasant life, the engaged life and the meaningful life” (Dawkins, 2006), animal happiness may be classified into “everyday sensational pleasures, engaging with their environment, their conspecifics and their handlers, and realizing their goals” (Dawkins, 2006).  This classification system may be used to assign feelings, both positive and negative, to different behaviours.  For example, the positive/negative affective outcomes of eating might be described as pleasure/over-fullness and those of play as tactile pleasure/tactile pain.  By looking at both the positive and negative outcomes (and their corresponding feelings) in a relative way, welfare scientists can more effectively increase positive welfare and minimize negative states (Yeates, 2008).

“It’s about time that the skeptics and naysayers have to prove their claims that animals don’t experience emotions or don’t really feel pain, but just ‘act’ as if they do. Until such claims are proven, let’s assume that animals do experience rich emotions and do suffer all sorts of pain” (Beckoff, 2007).

“Of course animal emotions are not necessarily identical to ours and there is no reason to think they must be. Their hearts and stomachs and brains also differ from ours and from those of other species, but this doesn’t stop us from saying that they have hearts, stomachs and brains. There is dog-joy and chimpanzee-joy and pig-joy, and dog-grief, chimpanzee-grief, and pig-grief” (Beckoff, 2007).



Beckoff, M. (2007). The Emotional Lives of Animals: A Leading scientist explores animal joy, sorrow, and empathy - and why they matter. California, New World Library.

Dawkins, M. S. (2006). Through animal eyes: what behavior tells us. Applied Animal Behaviour Science .

Fraser, D. A. (2009). Applied animal behavior and animal welfare. In J. J.-A. Bolhuis, The Behavior of Animals: Mechanisms, Function and Evolution (pp. 345-366). Malden: Blackwell Publishing.

Yeates, J. W. (2008). Assessment of positive welfare: a review. The veterinary journal 175 , 293-300.