Agriculture Reference
In-Depth Information
has the advantage of preventing the animals from the stress of being isolated. There
are many tools that stockpersons can use during the transfer in order to facilitate the
process. Some tools like electric prods are very aversive to the pigs (Gonyou
et al.,
1986;
Hemsworth and Barnett, 1991; Hemsworth
et al.,
1996a). Fowler (2008) proposed the
use of sticks or shields which are much less aversive. Stockpersons may also simply use
their body to direct the animals: they can place themselves behind the animals, speak
loudly, and push them with the hand. The effectiveness of these various methods is not
clear, and their use would depend on the habits of the stockperson. However, pigs were
shown to be sensitive to the posture of humans (Hemsworth
et al.,
1986c; Miura
et al.,
1996; Nawroth
et al.,
2014), and thus the human position and posture may impact the
ease of transfer. The response of pigs to human voice is not known but pigs are stressed
by high-pitched and/or loud sounds (Eguchi
et al.
, 2007; Weeks, 2008), and thus speaking
loudly or shouting may negatively impact the transfer. Pigs are also sensitive to human
tactile contacts (Hemsworth and Coleman, 2011) and could be affected by being pushed
by a shield or hands. These contacts may not facilitate the transfer since it was shown that
the speed of transfer was negatively correlated with the number of pushings done by the
stockperson (Lensink
et al.,
2009a). However, a greater incidence of pushing could be the
consequence rather than the cause of a difficult transfer. Beside human behaviour, the
configuration of the route may impact the ease of transfer (Grandin, 2010).
To our knowledge, physiological and behavioural data measuring the level of stress
perceived by the animals during routine transfers in the piggery are not available.
However, it is well known that using electric prods (Gonyou
et al.,
1986; Hemsworth and
Barnett, 1991; Hemsworth
et al.,
1996a) increases the release of cortisol and it is likely
that any rough handling (shouts, kicks…) is stressful for the animals.
12.3.2
Impact of other husbandry tasks
Sows are repeatedly handled for various husbandry tasks. These human-animal
interactions can be aversive to the animals for two reasons: they are either painful by
themselves (injections with needles for example) or the handling is accompanied by
shouts, snaps, hits, kicks. When these interactions are not painful by themselves, such
as oestrus detection or pregnancy diagnosis with ultrasounds, they can be neutral or
positive depending again on the behaviour of the stockperson.
When sows are kept outdoors, it is common to insert a nose-ring in order to prevent them
from rooting and damaging the pastures. It is an efficient procedure for that purpose but
it modifies the behaviour in a way that suggests reduced welfare (Horrell
et al.,
2001). It is
likely that the procedure of nose ringing is painful and that the animal will again associate
human handling to pain but scientific data are missing to substantiate this hypothesis.
Sows are often vaccinated by injections and it is probably aversive. Indeed, a subcutaneous
injection of saline in the elbow of cyclic gilts or lactating sows was shown to increase
circulating cortisol concentrations, indicating a stress reaction (Robert
et al.,
1989). he
procedure of injections may also increase the fear of humans. Indeed, after three weeks
of daily intra-muscular injections of saline to growing pigs, pigs were less confident to
