Genetics and Behavior During Handling, Restraint, and Herding - Genetics and the Behavior of Domestic Animals - page 129

horses from 9 to 22 months of age, Visser et al. (2001) measured individual
variation and consistency of behavioral variables related to temperament.
One out of four temperament traits, “flightiness” (novel object test), proved
to be consistent over time.
Kilgour (1975) used the open-field test as an assessment of temperament
in dairy cows. Le Neindre et al. (1995) documented individual differences in
docility of Limousin cattle. In this study, cattle were separated from herd
mates by a person working their flight zone. Individuals were considered
aggressive if they lowered their heads or charged the handler. This test may
have been measuring separation distress (PANIC) instead of aggression.
Murphey et al. (1980) found he could approach dairy breeds more closely
than beef breeds. Individual differences also affect grazing behavior. In cattle
with similar genetics, some individuals prefer to graze on steeper slopes
compared to other individuals that prefer flatter ground ( Bailey et al., 2004 ).
Grandin (1992) assessed the temperament of bulls during restraint in a
squeeze chute four times at 30-day intervals, and concluded that in order to
obtain accurate temperament evaluations on individual animals, each animal
should be scored more than once. Temperament scores were stable over time
for the calmest individuals and stable over time for the most agitated indivi-
duals. A test conducted four times easily identified the extremely calm indi-
viduals versus the extremely agitated. Wild Bighorn sheep show a similar
stability of temperament over time. Reale et al. (2000) reported that behavior
during capture was similar during repeated captures.

Effect of Pig Genetics on Behavior During Handling
Using several different handling tests, Lawrence et al. (1991) compared two
separate groups of modern hybrid Cotswold Landrace Large White pigs.

Both groups were reared under the same conditions, but differed in their
behavior. The first author also observed differences in behavior of the same
genetic line of hybrid pigs on different farms. Pigs from one farm were cal-
mer than pigs from another farm. The first author speculates that differences
are due to differences in how the managers selected breeding stock and dif-
ferences in handling. One farm had a scale that was difficult to read if a pig
became highly agitated in it. This may have caused the manager to select
calmer breeding stock.
Handling tests used by Lawrence et al. (1991) were: (1) willingness to
leave the home pens; (2) movement ease through a hallway; (3) response to
a suddenly approaching human; (4) restraint-resistance using a snout snare;
and (5) vocalization during restraint. With the exception of vocalization, all
tests had a strong tendency to correlate. The single-best predictor of tempera-
ment was a suddenly approaching human who stamped his foot. The
response was scored on a five-point scale: (1) no response; (2) mild flinch;
(3) animal backed away from the person; (4) animal backed away and

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