How Studying Interactions Between Animal Emotions, Cognition, and Personality Can Contribute to Improve Farm - Genetics and the Behavior of Domestic Animals - page 83

non-specificity of stress responses, reported earlier by Selye, was due to the
common emotion—felt by the animal—that triggers stress responses.
It is now well known that stress responses vary in form depending on
how the individual perceives the situation and its coping possibilities, such
as whether the animal engages in a passive response (e.g., immobility) or an
active one (e.g., fight or flight) ( Dantzer and Morm`de, 1983; Veissier and
Boissy, 2007 ). Likewise, it became clear that the ability to predict the occur-
rence of a stressful event—painful or not—and to control the termination of
that event also affects stress responses ( Weiss, 1972 ). This prompted scien-
tists to suggest that animal welfare was closely linked to cognitive processes
such as an awareness of some internal state (being hungry, being dis-
eased

), expectancies about the environment (which help animals to detect
whether something is absent or not), and the ability to predict or control the
animal's environment ( Duncan and Petherick, 1989; Wiepkema, 1987 ). From
an adaptation perspective, the ability to perceive its own emotions enables
the animal to detect and assess a discrepancy between its requirements and
environmental conditions and the efficiency of its subsequent action to
regain homeostasis. In addition, the subjective emotional experiences repre-
sent motivational urges or drives that are predominantly negative and include
breathlessness, thirst, hunger, and pain ( Mellor, 2012 ). Therefore, in order to
illustrate the variety of approaches in emotion studies, we focus the follow-
ing part on fear and anxiety because they are the most studied and the poten-
tially most damaging of the emotions ( Jones and Boissy, 2010 ).

...

Fear and Anxiety
Fear is generally defined as a response to the perception of actual danger,
whereas anxiety is regarded as the reaction to a potential threat ( Boissy,
1998 ). Fear-related reactions are characterized by physiological and behav-
ioral components that prepare the animal to deal with the danger. Such
defensive reactions promote fitness: an animal's life expectancy is obviously
increased if it can avoid sources of danger such as predators ( Panksepp and
Burgdorf, 2003 ). Although captive animals have few natural predators, the
behavioral and physiological emotional responses persist ( Dwyer, 2004 ).
Moreover, domestic animals reared on ranges may still experience severe
predation by wild animals or dogs ( Asheim and Mysterud, 2005 ). Farm ani-
mals also show predator-avoidance reactions to human contact, even though
reduced fear of human beings has been a major component of domestication
(e.g., in herbivores: Price, 1984 ). Routine management procedures like shearing,
castration, tail docking, beak trimming, dehorning, vaccination, harvesting, herd-
ing, and transportation also cause fear and distress in cattle, sheep, and poultry
( Gentle et al., 1990; Hargreaves and Hutson, 1990; Manteca et al., 2009; Wohlt
et al., 1994 ). In addition, intense fear can cause chronic stress which may
compromise the expression of fundamental behaviors (social, sexual, parental)