Agriculture Reference
In-Depth Information
agreeability etc.). Humans are receivers of these expressions and could interpret them to
react accordingly. There are evidences from empirical studies that there is some contagion
of emotion (both suffering and happiness) between pigs and humans, suggesting some
understanding of the pigs' state by stockpersons (Fiorelli
et al.,
2012; Porcher, 2011).
Some publications showed that humans are sensitive to signals from pigs and attempt
to interpret their meaning. For example, the vocalizations emitted by piglets during a
painful practice such as surgical castration can be interpreted by humans as indicating
a strong emotional state with a negative valence (Tallet
et al.,
2010). Interestingly, pig
caretakers seemed to interpret these vocalizations less negatively than naïve students and
more experienced ethologists. The repeated hearing of these negative sounds may lead to
habituation (Talling
et al.,
1998) but stockpersons may also use a kind of psychological
defence to protect them or detach them, such as exhibited by veterinary students towards
animal suffering (Paul and Podberscek, 2000).
Body language of animals is also of importance in the evaluation of their emotionality.
Welmesfelder and her colleagues developed a method to assess the animal as a whole
using videos, the so-called 'qualitative assessment' method, to evaluate emotionality
(Wemelsfelder, 2007). Its efficiency to evaluate emotionality of many species, including
pigs, has been proven (Wemelsfelder
et al.,
2000, 2003, 2012). Indeed, results using this
method are correlated with quantitative observations of behaviour such that, for instance,
animals can be classified as nervous, tense or fearful. In addition, this evaluation is highly
repeatable and does not seem to depend on previous experience of humans with the
animals (Wemelsfelder
et al.,
2012).
Consequently, stockpersons can perceive and interpret the signals emitted by pigs, and
this can be a basis for them to adapt their contacts with the animals, provided they
do not develop an indifferent attitude towards the pigs. Such an understanding of pigs'
behaviour should be used to develop practical solutions when a stockperson faces an
animal expressing negative states like fear or pain; the aim being to decrease those
expressions associated with poor welfare. Such an adaptation should benefit the pigs but
also the handler. Indeed, humans are sensitive to pigs being in a positive state (Fiorelli
et
al.,
2012; Tallet
et al.,
2010; Wemelsfelder
et al.,
2012). Developing a better understanding
of the pigs' needs by the stockpersons handling them could lead to less negative reactions
from the pigs which could, in turn, help to increase the satisfaction of workers since
there is a direct link between animals' behaviour and job satisfaction (Hemsworth and
Coleman, 2011).
12.6
Conclusions
Interactions between sows and humans occur throughout the life of sows and may influence
the subsequent way the sows will react to humans, especially their fear reactions. These
interactions are not evenly distributed during the sow's life but occur more frequently
at special moments: shortly after birth, around breeding (oestrus detection, artificial
insemination), and around farrowing. The quality of the sow-human interactions may
influence the reproductive performance of the animals via different types of mechanisms
