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between litters of the same breeds. Highly reactive pigs are vigilant and
intensely aware of changes in their environment. Vigilance and reactivity
may facilitate certain types of learning. The first author has observed that by
confronting an animal with sudden novelty, the animal is more likely to
show its true reactivity or level of fearfulness. Flight zone is possibly more
affected by learning than reaction to a sudden novelty. For example,
Hereford cattle, a generally calm, placid breed, may have large flight zones
when raised where they seldom see people. But even extensively raised
Herefords seldom become highly agitated and struggle violently in a squeeze
chute. On the other hand, tame halter broke individuals of Saler or Limousin
cattle in the U.S. are much more likely to go berserk when suddenly con-
fronted with the novelty of an auction ring, compared to extensively raised
Herefords.
Animals with a Fearful Temperament Have More Violent
Reactions to a Sudden Novelty
Both authors have observed that the most reactive and fearful animals of a
group are more sensitive to changes in the environment, and usually first to
orient toward novel sights or sounds. Highly reactive herd animals constantly
rotate their ear positions, raise their head quickly from the ground when
grazing, excessively flick their tails, flinch when touched, or move away
when approached by people. These behaviors are all signs of a highly vigi-
lant reactive nervous system. Research studies and anecdotal observations
suggest that responses to sudden placement in a novel environment, or
reactions to sudden novel stimulus are very effective for identifying highly
fearful animals. Cattle entering a novel auction ring and suddenly being con-
fronted with people and noise, is analogous to being placed in a novel open
field test, or suddenly stamping your foot in a group of pigs. Animals with
genetically higher levels of nervous system reactivity and fearfulness are
more likely to have violent reactions to a sudden novel stimulus ( Grandin,
1997 ). In sheep, there is a relationship between high cortisol levels after
slaughter and increased vocalization and vigilance during on-farm behavior
tests ( Diess et al., 2009 ). It is likely the sheep in this study were reacting to
the sudden novelty of the slaughter plant.
Animal Reaction to Novelty is Very Specific
Animals do not generalize well between different objects or stimuli. Leiner
and Fendt (2011) find that horses habituated to a stationary blue and white
umbrella show fear to an unfamiliar orange tarp. After habituation-training
to the object, the fear-response to the object is specifically attenuated
whereas the fear response to another object remains. Cattle with a very small
flight zone when handled by a man on horseback have a much larger flight
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