ABSTRACT: There is evidence that season and truck/
trailer design play important roles in pig welfare during
transportation although little is known about their
interaction and effect on pig behavior. This experiment
was designed to examine the influence of season and
truck/trailer design on the behavior during loading, transit,
unloading, and lairage of market-weight pigs transported
to slaughter. A total of 3,756 pigs were transported on
either a 3-deck pot-belly trailer (PB; n = 181 pigs/wk in 8
experimental compartments) or a double-decker hydraulic
truck (DD; n = 85 pigs/wk in 4 compartments) for 2 h
to a commercial abattoir in summer and winter (6 wk in
each season). Density on both vehicles was 0.40 m2/pig.
Accounting for the number of pigs, loading took longer
(P = 0.033) onto the DD than the PB, but season did not
(P = 0.571) influence loading time. Pigs loaded onto the
PB moved backward more (P = 0.003) frequently than
those loaded onto the DD.